Compiled by the National Corn Growers Association

Transcription

1 Compiled by the National Corn Growers Association

2 DISTILLERS GRAINS FEEDING RECOMMENDATIONS The purpose of this document is to provide an introductory source of information on distillers grains feeding recommendations for beef, dairy, swine and poultry. This guide is by no means a comprehensive resource for distillers grains feed guidelines. Instead, it is meant to provide a small sample of recent feeding recommendations and associated research. The distillers grains inclusion levels recommended in each of the respective papers in this book may vary slightly and are based on independent feeding trial results. These recommendations are based on extensive research conducted by animal scientists and nutritionists from leading universities. The National Corn Growers Association provides these feeding recommendations to assist producers in understanding generally-accepted feeding levels. However, all rations for specific herds should be formulated by a qualified nutritionist. Moreover, the NCGA has no control over the nutritional content of any specific product which may be selected for feeding. NCGA makes no warranties that these recommendations are suitable for any particular herd or for any particular animal. The NCGA disclaims any liability for itself or its members for any problems encountered in the use of these recommendations. Background: Continued rapid expansion in the ethanol industry will mean explosive growth in the supply of distillers grains. Ethanol production in the United States has grown dramatically in the past five years, and following passage of the Renewable Fuels Standard in 2005, this growth is expected to further accelerate. The industry produced 3.41 billion gallons of ethanol in 2004, nearly two and a half times the 1.47 billion gallons produced in Approximately 4 billion gallons will be produced in 2005, according to industry estimates. During the 2004/05 crop year, billion bushels of corn went to ethanol production, according to USDA. For the 2005/06 crop year, it is estimated that 1.5 billion bushels of corn will be used in ethanol, representing 14 percent of projected U.S. corn production. A coproduct of dry-grind ethanol production is distillers grains, which are used by the livestock and poultry industries as a source of energy and/or protein in feed rations. The most common forms of distillers coproducts generated by dry-grind ethanol plants include: Distillers Wet Grains (DWG); Distillers Dried Grains (DDG); Distillers Wet Grains with Solubles (WDGS); Distillers Dried Grains with Solubles (DDGS); and Condensed Distillers Solubles (CDS). Wet and dried distillers grains with solubles are the most common forms of distillers grains being marketed to livestock and poultry producers today. According to industry sources, approximately 60% of distillers grains are sold domestically and internationally in the form of DDG or DDGS. The remaining 40% are sold domestically as WDG or WDGS for use in ruminant feed markets, normally in close proximity to the plant producing the WDG and WDGS. Ethanol plants produced approximately 7.3 million tons of distillers grains in Of that amount, more than 6.5 million tons (89%) were consumed domestically, while 786,603 tons (11%) were exported. Dry grind plants are projected to produce 8.89 million tons of distillers grains in the 2005/2006 crop year and more than 10 million tons in 2006/2007. Assuming that the majority of future ethanol growth will be in dry grind production, it is estimated that plants will be generating approximately 16 million tons of distillers grains in 2012, or more than twice the amount produced in Accordingly, more distillers grains will be entering the feed market with each passing year.

3 Nutrient Profile New generation distillers dried grains with solubles are an excellent source of protein and energy for livestock and poultry. Because the distillers grains from each plant are slightly different in composition and nutritional value, a standard nutrient profile does not exist. However, the profiles below are typical of most new generation distillers grains. The analyses below are representative of DDGS only. For typical analyses of DDG, WDG or WDGS, consult your nutritionist or local extension agency.

4 Source: Dr. Gerald Shurson, University of Minnesota

5 Dry-Grind Ethanol Production Coproduct Definitions Source: Association of American Feed Control Officials (AAFCO) Feed Ingredient Definitions Corn Distillers Dried Grains (DDG) is obtained after the removal of ethyl alcohol by distillation from the yeast fermentation of corn by separating the resultant coarse grain fraction of the whole stillage and drying it. (27.5) Corn Distillers Dried Grains with Solubles (DDGS) is obtained after the removal of ethyl alcohol by distillation from the yeast fermentation of corn by condensing and drying at least ¾ of the solids of the resultant whole stillage. (27.6) Corn Distillers Wet Grains (DWG) is the product obtained after the removal of ethyl alcohol by distillation from the yeast fermentation of corn. (27.8) Corn Condensed Distillers Solubles (CDS) is obtained after the removal of ethyl alcohol by distillation from the yeast fermentation of corn by condensing the thin stillage fraction to a semi-solid. (27.7) NOTE: Official AAFCO definitions do not exist for Distillers Wet Grains with Solubles (DWGS) and the variety of modified distillers grains products currently on the market. SPENT MASH GRAINS FRACTION SOLUBLES FRACTION DISTILLERS DRIED GRAINS DISTILLERS WET GRAINS CONDENSED SOLUBLES (SYRUP) DRIED SOLUBLES DDGS DISTILLERS DRIED GRAINS W/SOLUBLES DWGS DISTILLERS WET GRAINS W/SOLUBLES

6 General Reference Data U.S. U.S. DDGS DG Consumption by by Species Share of consumptio 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Dairy Beef Poultry Swine Source: Commodity Specialists Company 8000 DDGS U.S. DG Production & and Use Use 000 mt Sources: ProExporter Network; Foreign Ag Service Total Production Fed domestic Export

7 U.S. Ethanol and & DG DDG Production Projections Projections Ethanol mmgy DDG 000mt Ethanol (mmgy) DDG (000mt) Source: ProExporter Network

8 Additional Information The following web-based resources provide extensive information on the use of distillers grains in livestock and poultry rations: University of Minnesota Distillers Grains Web Site: The Value and Use of Distillers Dried Grains with Solubles (DDGS) in Livestock and Poultry Feeds, Distillers Grains Technology Council, Iowa Department of Agriculture and Land Stewardship, Office of Renewable Fuels and Coproducts, Distillers Feeds: Using Illinois By-Product Feeds in Livestock Feeding Programs, Feedstuffs Magazine, Additionally, most university extension services offer educational tools and services related to use of distillers grains. Many state corn grower associations also offer information on the use of distillers grains. Acknowledgements The NCGA Ethanol Committee and Production and Stewardship Action Team would like to thank the following individuals for reviewing these feeding recommendations and providing input on this book s content: Dr. Sally Noll, University of Minnesota Dr. Terry Klopfenstein, University of Nebraska Dr. David Schingoethe, South Dakota State University Dr. Allen Trenkle, Iowa State University Brett Lumpkins, University of Georgia Greg Lardy, North Dakota State University Dr. Hans Stein, South Dakota State University John Goihl, Agri-Nutrition Services The photographs used in this document are courtesy of USDA-ARS and Dr. Sally Noll, University of Minnesota, and are used by permission. Solicitation It is NCGA s intention to update this document periodically with new feeding recommendations as they become available. Distillers grains feeding recommendations may be submitted to NCGA at corninfo@ncga.com for consideration in future volumes. For more information, call (636)

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12 Summary of Distillers Grains Feeding Recommendations for Beef WDGS can be added to corn-based rations for finishing cattle at levels ranging from 10 to 40% of total ration dry matter. When added at levels ranging from 10-25% of ration dry matter, WDGS has greater apparent energy value than corn grain. DDGS has an apparent energy value equal to corn grain when fed to finishing cattle at levels ranging from 10 to 20% of total ration dry matter. When CDS is fed to finishing cattle at 10% or less of ration dry matter, its apparent energy value is equal to or somewhat greater than corn grain. Dr. Allen Trenkle, Dept. of Animal Science, Iowa State University, The Advantages of Using Corn Distillers Grains in Finishing Beef Cattle Diets (Iowa Corn Growers Association brochure), 2004 Nebraska and Iowa research suggests that distillers grains (wet or dry) at up to 40% of the diet dry matter can replace corn for growing and finishing cattle. feeding distillers grain at 15-20% of the diet dry matter has improved average daily gain and efficiency of gain. Kent Tjardes and Cody Wright, Feeding Corn Distiller s Co-Products to Beef Cattle, South Dakota State University Extension Service Extension Extra, ExEx 2036, August 2002 Distillers grains (wet or dry; with or without solubles) can be fed at 10 to 15% of the diet (DM basis) as a source of supplemental protein in backgrounding and finishing diets. When fed at levels higher than 15% of the diet, distillers grains are also an energy source, replacing corn or other grains in the diet. DDG can be fed at levels up to 20% of the diet DM. WDG can be included in backgrounding and finishing diets at levels up to 40% the diet DM. Dr. Greg Lardy, Feeding Coproducts of the Ethanol Industry to Beef Cattle, North Dakota State University Extension Service Publication AS-1242, April 2003 Distillers grains are an excellent ruminant feedstuff...the DG can be fed at 6 to 15% of the diet dry matter, serving primarily as a source of supplemental protein. When fed at higher levels (greater than 15% of the diet dry matter), the byproduct s primary role is as a source of energy replacing corn grain. Dr. Terry Klopfenstein, University of Nebraska-Lincoln, Distillers Grains for Beef Cattle, National Corn Growers Association Ethanol Coproducts Workshop, Lincoln, Neb., Nov The National Corn Growers Association provides these feeding recommendations to assist producers in understanding generally-accepted feeding levels. However, all rations for specific herds should be formulated by a qualified nutritionist. Moreover, the NCGA has no control over the nutritional content of any specific product which may be selected for feeding. Producers should consult an appropriate nutritionist for specific recommendations. NCGA makes no warranties that these recommendations are suitable for any particular herd or for any particular animal. The NCGA disclaims any liability for itself or its members for any problems encountered in the use of these recommendations. By reviewing this material, producers agree to these limitations and waive any claims against NCGA for liability arising out of this material.

13 The Advantages of Using Corn Distillers Grains in Finishing Beef Cattle Diets Wet corn distillers grains with solubles (WDGS) is an excellent feed for finishing cattle Research at Iowa State University as well as other universities has shown that WDGS can be added to corn-based rations for finishing cattle at levels ranging from 10 to 40% of total ration dry matter. WDGS is palatable and readily consumed by cattle. Because the concentration of starch is less than corn grain, WDGS is less likely to cause subacute acidosis in cattle fed low-roughage rations. Quality and yield grades of carcasses from cattle fed WDGS are similar to those fed corn grain. Feeding WDGS did not change sensory values of steaks. When added at levels ranging from 10 to 25% of ration dry matter, WDGS has greater apparent energy value than corn grain. When used to replace part of the corn and supplemental protein, WDGS improves feed conversion and reduces feed cost of gain when cost of WDGS (including transportation and storage) is equal to or less than cost of corn on a dry basis. For each $0.25 increase in corn price/bu, the value of WDGS (30% dry matter) as a feed for finishing cattle increases $3.75/ton. Dry distillers grains with solubles (DDGS) can be fed to finishing cattle to replace protein supplement and corn DDGS has an apparent energy value equal to corn grain when fed to finishing cattle at levels ranging from 10 to 20% of total ration dry matter. DDGS also is palatable and readily consumed by cattle. Feeding DDGS does not change quality or yield grades of carcasses. Feed cost of gain will be reduced if the cost of DDGS is not greater than cost of corn grain on a dry basis. For each $0.25 increase in corn price/bu, the value of DDGS (90% dry matter) as a feed for finishing cattle increases $9.50/ton. Condensed distillers solubles (CDS) has value as a feed for finishing cattle CDS is a liquid that typically contains 30% dry matter. When CDS is fed to finishing cattle at 10% or less of ration dry matter, its apparent energy value is equal to or somewhat greater than corn grain. Feeding at levels greater than 10% of ration dry matter might reduce feed intake. Feeding CDS has not changed quality or yield grades of carcasses. For each $0.25 increase in corn price/bu, the value of CDS (30% dry matter) as a feed for finishing cattle increases $3.00/ton. Corn distillers grains (DG) as feeds for other classes of cattle Less research has been done with other classes of cattle, but the coproducts are excellent feeds to supplement energy and protein of lower quality forages. Because of the low starch content of DG, these feeds have less negative effects than high starch feeds on fiber digestion in the rumen. When fed to supplement low phosphorus forages, the phosphorus in DG will be of value. Potential uses of co-products include creep feed for calves, supplements for grazing cattle, and supplements for low quality forages such as crop residues that might be fed to growing calves, wintering beef cows, or developing beef heifers. 05/19/2004

14 Keys to feeding distillers grains (DG) to beef cattle o When price of DG is low compared with corn grain, there are greater profits from feeding higher levels. o Make changes in the ration to account for the nutrients being supplied by DG, namely protein and phosphorus. o Maintain adequate quantities of effective fiber in rations containing DG for finishing cattle. o Keep the supply of WDGS fresh. o CDS should be mixed when stored for longer periods of time. o Feed finishing cattle to similar final weights as those not fed DG. For additional information on feeding distillers grains to cattle contact: Allen Trenkle Department of Animal Science Iowa State University Ames, Iowa /19/2004

15 Extension Extra ExEx 2036 August 2002 Animal & Range Sciences COLLEGE OF AGRICULTURE & BIOLOGICAL SCIENCES / SOUTH DAKOTA STATE UNIVERSITY / USDA Feeding Corn Distiller s Co-Products to Beef Cattle Kent Tjardes and Cody Wright Extension beef specialists The ethanol industry is currently in the midst of a considerable expansion period in South Dakota and surrounding states. As more ethanol plants are built and begin production, the availability of co-products for livestock feed will increase dramatically. Co-products may offer the cattle industry a tremendous opportunity to reduce feed costs without sacrificing performance. However, there are significant challenges that must be met before feeding these products. The majority of the new plants utilize a dry milling process to produce ethanol from corn. Dry milling (mash distillation) involves cleaning and grinding the grain into coarse flour. Then water and enzymes are added, which convert the starch into sugar. At this point the mixture, referred to as "mash," is cooked and sterilized. Once the mash has cooled, yeast is added to begin the fermentation process. Fermentation results in the production of ethanol, carbon dioxide, and residual grain particles called "spent mash." The entire mixture is then distilled to remove the ethanol and centrifuged to remove as much excess liquid as possible. Dry Milling Co-Products Liquid removed from the mash is called thin stillage or "sweet water." Thin stillage may be reintroduced into the cooking and distillation processes to extract residual ethanol, sold directly as livestock feed, or dehydrated to produce condensed distiller's solubles (CDS), or syrup. The remaining solid fraction, called wet distiller's grains (WDG), may be sold directly as livestock feed or dehydrated to produce dried distiller's grains (DDG). Condensed distiller's solubles are either sold directly as cattle feed or blended with the distiller's grains to produce distiller's grains + solubles. Distiller's grains + solubles are sold in wet (WDGS; 30% DM), modified (MDGS; 50% DM), or dry forms (DDGS; 90% DM). One of the first challenges in using distiller s co-products is to determine the nutrient content of the co-product used. As with other co-products (soybean meal, soyhulls, sunflower meal, etc.), nutrient concentrations in distiller s coproducts can be highly variable. Table 1 contains a list of commonly reported nutrient values for different distiller's co-products. Some variation in nutrient concentrations results from differences in the nutrient content of the corn used to produce ethanol. Differences in types of yeast, fermentation and distillation efficiencies, drying processes, and amount of solubles blended back into each of the co-products may also result in nutrient variability. Some plants may provide product specifications with guaranteed nutrient contents; however, these values are only estimates of the minimum or maximum nutrient content of a particular co-product. Testing each load is the preferred option to assess the actual nutrient concentrations of any co-product feed. When feeding co-products

16 that have limited shelf life (CDS, WDG, WDGS), however, this is not a practical option. Therefore, at the minimum, dry matter should be determined to assess how many pounds or tons of dry matter you are purchasing and feeding to the cattle. Feeding Distiller's Co-Products Thin Stillage. Thin stillage contains only 5-10% dry matter and can be used to replace water in cattle feeding operations. Research suggests that replacing water with thin stillage reduces dry matter intake without negatively affecting performance. Cattle need to adapt over time to drinking the thin stillage. Not all cattle will consume the thin stillage, so these animals must be moved to pens with traditional water sources. Fountains and water lines should be cleaned frequently to prevent microbial growth. Diets must be adjusted to account for the additional nutrients when thin stillage is replacing water. Since the nutrient content can be highly variable, each new shipment of thin stillage should be sampled and analyzed. Condensed Distiller s Solubles. To produce CDS, thin stillage is frequently evaporated to approximately 70% moisture. Condensed distiller s solubles provide additional protein and energy and add moisture to condition diets. Experiments at SDSU suggest that the addition of CDS up to 10% of the diet dry matter improves average daily gain and efficiency of gain. Based on a 10% inclusion, a 700-lb steer consuming 18 lb of dry matter per day would get 1.8 lb dry matter from CDS, or 6 lb of CDS on an as-fed basis (Table 2). A 1000-lb steer would be fed 8 lb, and a lb cow would get less than 9 lb of CDS as fed. One note of caution: CDS may contain up to 15% fat depending on the source, and beef cattle diets containing more than 6% fat may depress fiber intake and digestion. When CDS is added at over 20% of the diet dry matter to diets that contain feedstuffs already containing 3% fat (such as early bloom alfalfa and corn grain), the dietary fat percentage can become greater than 6% 15% = 3%; 3% = 2.4%; 3% + 2.4% = 5.4%< 6%). Distiller s Grains. Distiller s grains with or without solubles are a medium protein feed and can be fed as a replacement for other protein sources (such as soybean meal, sunflower meal, urea, etc.) in beef cattle diets. The protein in distiller s grains is approximately 50% unde- 2 graded intake protein (UIP), commonly referred to as "bypass protein," and 50% degraded intake protein (DIP). Rumen microbes require a certain level of DIP to effectively digest starch and fiber and synthesize microbial protein. Microbial protein is the primary source of protein for beef cattle; however, forage-based diets may not allow for enough microbial protein production to meet the needs of the animal. Fortunately, much of the UIP provided by different feedstuffs is available for digestion in the small intestine. Often, a combination of microbial protein and UIP is necessary to meet the metabolizable protein requirements. Cattle consuming poor quality forages generally require DIP supplementation to improve diet digestibility and performance. For older, more mature cattle, supplementing a protein source that is high in DIP may be sufficient to meet nutrient requirements. However, heifers and young cows have greater nutrient requirements and may require UIP supplementation to meet their nutrient demands for growth, gestation, and lactation. Once the DIP requirement for forage digestion is met, supplementation of higher levels of UIP may improve growth of young cattle and reproductive performance. Supplements can be formulated from a variety of feeds to best meet the DIP and UIP requirements; however, DDG or DDGS can serve as the sole protein source for cattle. When feeding DDG or DDGS as a sole protein source, it is important to remember that higher levels of crude protein must be fed to effectively meet the DIP requirements. A good rule of thumb is that, to provide similar levels of DIP, it takes 2.7 lb of DDGS to replace 1 lb of 44% crude protein soybean meal. Distiller s grains are also an effective addition to feedlot diets. Nebraska and Iowa research suggests that distiller s grains (wet or dry) at up to 40% of the diet dry matter can replace corn for growing and finishing cattle. In many studies, feeding distiller s grains at 15-20% of the diet dry matter has improved average daily gain and efficiency of gain. Including distiller s grains up to 20% of the diet dry matter can usually be accomplished with cornbased diets that contain forages low in protein without creating excess nitrogen excretion. Kansas and Iowa research indicates that feeding distiller s grains at or above 40% of the diet dry matter may reduce performance and efficiency of gain and/or decrease carcass

17 quality when compared to lower levels. To feed a 700-lb steer consuming 18 lb of dry matter, a ration containing 20% distiller s grains, 4 lb DDG or 12 lb WDG, should be fed (Table 2). Besides the nutritional benefits of distiller's grains in feedlot diets, the moisture contained in WDG helps to condition dry rations. In addition to protein, distiller s grains contain highly digestible fiber and fat, resulting in a similar to slightly higher energy value than corn. By providing energy as highly digestible fiber, we can avoid negative associative effects (reduced forage intake and digestibility) associated with feeding starchy (high starch) feeds. Furthermore, the fiber contained in distiller's grains may help prevent digestive disturbances in feedlot cattle. Since dried and modified distiller's grains are subjected to a drying process, there is the potential for "burning." While the distiller's grains may not actually burn, prolonged exposure to heat or excess sugar may result in a chemical browning reaction that renders part of the carbohydrate and protein unavailable to the animal. This reaction is similar to that of overheated stacked alfalfa hay as a result of air infiltration. Generally, DDG, DDGS, MDG, and MDGS should have a bright, golden to golden brown color and smell somewhat like beer. If the product has been burnt, it will be considerably darker and have a burnt molasses odor. Suppliers will often discount the price of a burnt product to account for the reduction in feed value. The price should reflect the decrease in energy and available protein, and to accurately estimate these values the burnt product must be sampled and tested. The lab analysis should include ADIN (acid detergent insoluble nitrogen) to assess the extent of protein damage. Since the ADIN value only represents nitrogen, it must be multiplied by 6.25 to calculate the appropriate protein value. The calculated protein value represents the amount of crude protein that is unavailable. For example, if a sample contains 1.2% ADIN, then the unavailable protein value is 7.5% (1.2 x 6.25). Thus, if the sample contains 30% crude protein, only 22.5% crude protein is available ( ). 3 Mineral Considerations When feeding distiller s grains, keep in mind how the mineral concentrations of the diets are affected. Distiller s grains are low in calcium (Ca) but high in phosphorus (P) and sulfur (S). Feeding distiller's grains may provide enough P to allow supplemental P sources to be removed from mineral packages for cattle consuming forage-based diets. Feedlot diets generally contain excess P due to the high levels of corn, so, when distiller's co-products are utilized, the additional P must be considered when formulating waste management plans. Also, to facilitate proper performance and to avoid urinary calculi (water belly), Ca to P ratios should be equal to or greater than 1.2:1 but not greater than 7:1. Supplemental Ca can be provided from feedstuffs high in Ca (alfalfa), but it is more commonly supplemented as limestone. Distiller's grains are also frequently high in sulfur. Excess dietary S can be a problem for ruminants for two reasons. First, high levels of sulfur (above 0.4% of diet dry matter) from feed and water can lead to polioencephalomalacia (PEM), or "brainers." Second, sulfur interferes with copper absorption and metabolism. This antagonism is exacerbated in the presence of molybdenum. Producers in regions prone to high sulfate water should exercise caution if using distiller's grains in their supplements. Storage Considerations Storage is also a major challenge when using co-products. Since CDS and thin stillage contain a high percentage of moisture, they will gel and freeze in cold temperatures. Storage equipment to prevent these products from freezing is necessary. Storage tanks should either be buried or heated for long-term storage in the winter. Some of the solids in these products can also separate from the liquid. Therefore, the ability to re-circulate or agitate the tank may also be advantageous for long-term storage. Wet distiller s grains with or without solubles contain about 70% moisture, which makes them challenging to store. This product can freeze into softball size clumps during the winter, making mixing the ration more difficult and and the resulting feed less consistent.

18 Handling WDG in warmer weather can be even more challenging. Wet distiller s grains will mold and go out of condition in as few as 4 days, although typically, WDG have about 7 days of shelf life before going out of condition. Organic acid may extend shelf life, but the additional cost needs to be considered. Wet distiller's grains have been successfully stored for more than 6 months in silage bags, either bagged alone or in combination with another feed to increase bulk. SDSU researchers have been very successful storing blends of WDG (70% as-fed; 50% of dry matter) and soybean hulls (30% as-fed; 50% of dry matter). Dried distiller s grains, with or without solubles, are easier to store since they only contain 10-12% moisture. These products do have a small particle size, so storing DDG out of the wind is critical. Commodity bins or bulk storage sheds work best. Even though DDG have high levels of fat, rancidity during summer months is usually not a concern. Economics When determining the economic value of the co-products, comparisons should be made on an energy (Total Digestible Nutrients; TDN) and crude protein (CP) basis. 4 Table 3 illustrates what could be paid for the various distiller's co-products to replace corn on an equivalent energy basis. The equivalent values of the various co-products compared to soybean meal on a CP basis are presented in Table 4. Keep in mind these economics do not account for any additional costs associated with freight or storage; these expenses should be carefully evaluated when deciding on the value of any feedstuff. Summary Distiller's co-products offer beef producers an opportunity to potentially decrease their unit cost of production while maintaining similar levels of performance. The nutritional characteristics of distiller's co-products (high energy and medium protein levels) allow these feeds to be effectively incorporated into many feeding scenarios for many types of cattle. However, use of distiller's coproducts does require consideration of nutritional properties, storage, and, most importantly, economics. Careful assessments of nutrient, shipping, and storage costs are essential when deciding if distiller's co-products are economically viable alternative feeds for your operation. Table 1. Nutrient concentrations of corn co-products expressed on a dry matter basis a CDS WDG MDGS DDG DDGS Dry matter (DM), % Crude protein (CP), % Degradable intake protein (DIP), % of CP Fat, % Neutral detergent fiber (NDF), % Total digestible nutrients (TDN), % Net energy for maintenance (NEm), Mcal/lb Net energy for gain (NEg), Mcal/lb Calcium, % Phosphorus, % a Adapted from the National Research Council and industry publications. This publication and others can be accessed electronically from the SDSU College of Agriculture & Biological Sciences publications page at or from the Extension Service Drought Information Website at Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the USDA. Larry Tidemann, Director of Extension, Associate Dean, College of Agriculture & Biological Sciences, South Dakota State University, Brookings. SDSU is an Affirmative Action/Equal Opportunity Employer (Male/Female) and offers all benefits, services, and educational and employment opportunities without regard for ancestry, age, race, citizenship, color, creed, religion, gender, disability, national origin, sexual preference, or Vietnam Era veteran status. ExEx 2034: 150 copies printed by CES at a cost of 9 cents each. August 2002.

19 5 Table 2. Maximum inclusion rate of rates of co-products for different cattle types Co-product maximum inclusion rate (lb) Cattle Type Weight range (lb) WDG a MDGS a DDG a CDS b Growing calf Finishing steer Cow a Assuming maximum inclusion rate is 20% of dry matter intake; WDG, 30% DM; MDGS, 50% DM; DDG, 90% DM. b Assuming maximum inclusion rate is 10% of dry matter intake; CDS, 30% DM. Table 3. Equivalent value of co-products compared to corn on an energy (TDN) basis a Co-products ($/ton) Corn ($/bu) CDS WDG MDGS DDG DDGS a Assumptions: corn, 88% DM and 88% TDN; CDS, 30% DM and 97% TDN; WDG, 30% DM and 88% TDN; MDGS, 50% DM and 88% TDN; DDG, 90% DM and 88% TDN; and DDGS, 90% DM and 97% TDN. Table 4. Equivalent value of co-products compared to soybean meal (SBM) on a crude protein basis a Co-products ($/ton) SBM ($/ton) CDS WDG MDGS DDG DDGS a Assumptions: soybean meal,89% DM and 48% CP; CDS, 30% DM and 25% CP; WDG, 30% DM and 32% CP; MDGS, 50% DM and 32% CP; DDG, 90% DM and 32% CP; and DDGS, 90% DM and 30% CP.

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21 AS-1242 Feeding Coproducts of the Ethanol Industry to Beef Cattle Dr. Greg Lardy, Extension Beef Cattle Specialist Department of Animal and Range Sciences Ethanol industry coproducts, such as dried distillers grains, wet distillers grains and condensed distillers solubles (syrup) are becoming increasingly available as the ethanol industry expands. The purpose of this bulletin is to provide information on the feeding value of these coproducts for beef cattle and give cattle producers guidelines for their use in beef cattle rations. The ethanol industry in the United States is expanding rapidly, consequently, the amount of coproducts available for livestock feed is also expanding at a rapid rate. In North America, about 3.2 million metric tons of dried distillers grains plus solubles are produced annually. Minnesota, North Dakota and South Dakota produce about 900,000 tons annually. About 80% of this product is fed to ruminant animals. Ethanol Coproducts Corn contains approximately 61% starch, 3.8% oil, 8% protein, 11.2% fiber and 16% moisture. During ethanol production, starch is converted to ethanol and the other constituents of the corn kernel become coproducts. Each bushel of corn produces 2.7 gallons of ethanol, 18 pounds of dried distillers grains plus solubles and 18 pounds of carbon dioxide. Wet and Dry Distillers Grains North Dakota State University Fargo North Dakota APRIL 2003 Figure 1 diagrams the ethanol production process in a dry milling operation. Coproducts resulting from this process can include dry distillers grains (DDG), dry distillers grains with solubles (DDGS), wet distillers grains (WDG), wet distillers grains with solubles (WDGS) and condensed distillers solubles (CDS). Whole stillage, which is the liquid fraction remaining after ethanol production, is centrifuged to remove coarse solids and then evaporated to produce thin stillage. Thin stillage is further evaporated to produce CDS (sometimes referred to as syrup). The solids portion may be sold wet as WDG, combined with CDS and sold as WDGS, dried and sold as DDG, or combined with CDS, dried and sold as DDGS. The WDG and WDGS are approximately 30% dry matter (DM; 70% moisture) while the DDG and DDGS are approximately 90% DM. The wet coproducts (WDG or WDGS) have greater energy than DDG or DDGS because some of the volatile compounds can be given off during the drying process. However, protein quality does not seem to be affected by drying. Some processing plants may also market modified wet distillers grains plus solubles (MDGS), which are a partially dried product and are approximately 50% DM. Due to the high moisture content, transportation costs must be considered when purchasing WDG or MDGS.

22 Condensed Distillers Solubles (CDS) This syrup-like product remains after thin stillage has undergone partial evaporation. Thin stillage is the liquid (5% DM) product that remains following removal of wet distillers grains. Thin stillage is condensed through evaporation to produce condensed distillers solubles (23 to 45% DM). Condensed distillers solubles contain approximately 20 to 30% crude protein on a dry matter basis. Due to their liquid nature, condensed distillers solubles can be used to control dust and condition dry rations (similar to liquid molasses products). In most cases, condensed distillers solubles should be limited to 10% or less of the diet (DM basis; approximately 8 to 10 pounds per head on a wet basis). Figure 1. Ethanol and related coproducts production process diagram. Nutrient Content of Ethanol Coproducts Table 1 gives the average nutrient content for WDGS, MDGS, DDGS and CDS. Distillers grains are relatively high in crude protein, high in fat and are an excellent source of energy and protein for beef cattle. Distillers grains have a fermented aroma and are very palatable. Similar to corn value, the protein in corn distillers grains is high in escape protein (50 to 60% of the cp). Escape protein is not fermented in the rumen but is digested by the animal in the small intestine. Escape protein has some benefit in feeding programs where high performance is expected or where less than optimum levels of escape protein are provided in the diet. Ethanol coproducts are high in potassium, phosphorus and other minerals. Feeders should reduce or eliminate supplemental phosphorus, potassium and sulfur when high levels of these byproducts are fed. Increased levels of calcium should be considered in order to keep the calcium to phosphorus ratio in the diet at 2.0:1.0. Elevated levels of phosphorus in these coproducts may contribute Table 1. Nutrient composition of ethanol coproducts. Modified Dried Distillers Distillers Wet Condensed Dried Distillers Grains plus Grains plus Distillers Distillers Nutrient Grains Solubles Solubles Grains Solubles DM, % 88 to to to to 45 DM Basis TDN, % 77 to to to to to 120 NEm, Mcal/cwt 89 to to to to to 115 NEg, Mcal/cwt 67 to to to to to 93 CP, % 25 to to to to to 30 DIP, % CP 40 to to to to UIP, % CP 50 to to to to Fat, % 8 to 10 8 to 10 8 to 12 8 to 12 9 to 15 Calcium, % 0.11 to to to to to 0.17 Phosphorus, % 0.40 to to to to to 1.45 Potassium, % 0.49 to to to to to 2.25 Sulfur, % 0.46 to to to to to 0.95 Table adapted from: 1) Stock, et al Average Composition of Feeds Used in Nebraska. G ) Tjardes and Wright Feeding Corn Distiller s Co-Products to Beef Cattle. South Dakota State University. ExEx ) NRC Nutrient Requirements of Dairy Cattle. The analyses given in this bulletin are an average of published values and regionally available laboratory analyses. Products vary and this may not represent what a particular plant is producing at any give time.

23 to high levels of phosphorus in the manure and increase in the amount of land requied for proper nutrient management. In areas where high sulfate water is a problem, the high sulfur levels in ethanol coproducts may create problems with polioencephalomalacia (PEM). This disease affects the neurological system. Producers should consider elevating supplemental levels of copper and thiamine if diets high in ethanol coproducts will be fed for extended periods of time. The type and nutrient content of coproducts produced by ethanol plants will vary. Routine sampling and laboratory analysis is recommended in order to effectively use these coproducts. Moisture level in the wet coproducts does vary, consequently, a dry matter (moisture) analysis is one of the most important routine analyses to conduct. Producers may also ask the plant for a recent laboratory analysis. The analyses given in this bulletin are a range of published values and industry laboratory analyses and may not accurately represent what a particular plant is producing at a given point in time. Results from Feeding Trials Numerous research trials have evaluated DDG, WDG, WDGS and CDS as ration ingredients for beef cattle. Based on these research trials, it appears that WDGS have a greater energy value than corn. The energy content of WDGS depends on the level fed, the source of raw material for the ethanol facility (corn vs. other cereal grains), and possibly the moisture content of the material. Based on animal performance, the energy level of WDGS is at least 125% the energy level of corn. Research comparing the feeding value of dry distillers grains and wet distillers grains indicates that wet distillers grains are higher in energy than dry distillers grains. Reasons for the lower energy values for dried distillers grains could include 1) inclusion of some residual ethanol in the wet product, 2) moisture content of the wet distillers grains, 3) a reduction in subacute acidosis when wet distillers grains are fed, or 4) heat damage during drying. Most available research indicates the energy content of dried distillers grains is slightly lower than corn. Research with CDS and thin stillage indicate that these liquid coproducts have greater energy content than corn. Research conducted at the University of Nebraska indicates that inclusion of CDS in the diet improves ruminal fermentation by increasing starch and lactic acid utilizing bacteria. This suggests CDS improve animal performance by altering ruminal fermentation and enhancing starch digestion while reducing acidosis. Feeding Recommendations Backgrounding and Finishing Diets Distillers grains (wet or dry; with or without solubles) can be fed at 10 to 15% of the diet (DM basis) as a source of supplemental protein in backgrounding and finishing diets. When fed at levels higher than 15% of the diet, distillers grains are also an energy source, replacing corn or other grains in the diet. Dried distillers grains can be fed at levels up to 20% the diet DM. Wet distillers grains can be included in backgrounding and finishing diets at levels up to 40% the diet dry matter. However, at these levels, diets will contain excess protein and phosphorous, which may have manure nutrient management implications for many cattle feeders. Most research data indicates the optimum level of wet distillers grains is 25% or less of the diet dry matter. Condensed distillers solubles can be used as a conditioning agent, source of energy or source of protein. As a conditioning agent in the ration, CDS can be included at 5 to 10% of the diet dry matter. This level will help control dust and improve palatability of dry rations and increase energy and protein content of the diet. Although generally not included at levels above 10% of the diet dry matter, CDS are a good source of supplemental protein and energy in the diet. Forage-Based Diets for Beef Cows In forage-based diets for beef cows, distillers grains (wet or dry; with or without solubles) can be used as a source of supplemental protein and energy. The amount depends on the desired performance and nutrient content of the basal forage. In most cases, this would mean feeding up to 4 pounds of distillers grains per head per day on a DM basis. Condensed distillers solubles can be used as a source of supplemental protein for beef cows fed low quality hay. Mixing CDS with chopped hay is the most effective way to deliver it to the cow herd. Producers may also consider pouring it on top of hay in the feeder or other delivery mechanisms. Condensed distillers solubles may also be mixed with other dietary ingredients or supplements and delivered to the cow herd in that manner. High variability in intake can be expected if CDS is not mixed with the forage or other dietary ingredients and delivered to the cattle in a mixed ration. Creep Feeds Dried distillers grains and DDGS can be used as an ingredient in creep feeds. The flavor, aroma and nutrient characteristics of DDGS make it an excellent addition to creep feeds. Best results are obtained when DDGS are included at no more than 50% of the creep feed.

24 Storing Wet and Dry Distillers Grains Wet distillers grains and WDGS will mold rapidly (approximately seven days) during the summer. Cattle feeders should plan on feeding enough to use a truckload on a weekly basis during the summer to minimize spoilage problems. During the colder winter months, spoilage develops at a much slower rate, extending the storage time. However, storage should not exceed three to four weeks unless plastic silage bags or other oxygen limiting structures are used to limit spoilage. Wet distillers grains and WDGS can be stored in an oxygen-limiting environment such as plastic silage bags as a means of prolonging storage by limiting oxygen penetration. However, filling the bags can be difficult. If bags are packed too tightly, the bags can split as the WDG or WDGS settle. Care should be taken to not pack the bags too tightly. Holes should be patched or covered promptly to prevent spoilage. Wet distillers grains can be stored in bunker type silos and covered with plastic, however, some spoilage should be expected with this storage method. Dried distillers grains and DDGS can be stored in conventional grain storage structures or in flat storage such as a quonset. Be sure to check the moisture content prior to storage to reduce spoilage or bridging problems. For long-term storage, the moisture level should be below 15%. Material Handling Considerations for Liquid Coproducts The use of liquid ingredients like CDS will require purchase of liquid feed handling equipment if such equipment is not already in place. Most liquid handling systems can be installed with a modest equipment investment. The tanks should be either housed indoors or buried underground to prevent freezing of the liquid materials. Because some settling and separation occurs with these liquids, a recirculating or agitation pump may be necessary to reduce settling if the CDS will be stored for longer periods of time. Condensed distillers solubles should be agitated prior to adding it to the feed ration or mixer. Sources of Ethanol Coproducts in North Dakota Sources of dried distillers grains suppliers and contact information. Supplier Alchem, Ltd. Grafton, N.D. ADM Corn Processing Walhalla, N.D. Tri State Ethanol Rosholt, S.D Heartland Grain Fuels Aberdeen, S.D DENCO, LLC Morris, Minn Northern Lights Ethanol Big Stone City, S.D. Glacial Lakes Energy Watertown, S.D. Other plants may be found in Minnesota and South Dakota, but transportation costs should be factored in before purchasing coproducts and shipping them great distances. Summary Marketing Contact Commodity Specialist Company Dakota Commodities Coproducts from the ethanol industry are useful feed ingredients for beef cattle producers. Corn distillers grains are high in energy and protein and can be used in many different types of rations. Condensed distillers solubles can be used as a source of supplemental protein, a ration conditioner and a source of energy in beef cattle diets. However, because condensed distillers solubles are a liquid, they do require the purchase of liquid handling equipment. These coproducts can also vary in nutrient content and moisture level. Routine sampling and laboratory analysis is recommended and rations should be adjusted accordingly. AS-1242 NDSU Extension Service, North Dakota State University of Agriculture and Applied Science, and U.S. Department of Agriculture cooperating. Sharon D. Anderson, Director, Fargo, North Dakota. Distributed in furtherance of the Acts of Congress of May 8 and June 30, We offer our programs and facilities to all persons regardless of race, color, national origin, religion, sex, disability, age, Vietnam era veterans status, or sexual orientation; and are an equal opportunity employer. 3M This publication will be made available in alternative format upon request to people with disabilities (701)

25 Distillers Grains for Beef Cattle Terry Klopfenstein Distillers byproducts are excellent feed resources for feedlot cattle. Distillers byproducts are normally available for use in feedlot finishing diets in two forms, dried distillers and wet distillers byproducts (WDB). In general, there are two nutritional philosophies regarding their use in feedlot finishing diets. Distillers byproducts can be fed at 6 to 15% of the diet dry matter, serving primarily as a source of supplemental protein. When fed at higher levels (greater than 15% of the diet dry matter), the byproduct's primary role is a source of energy replacing corn grain. Other than dry matter content (wet distillers, 35-45%; dried distillers, 90-95%), the chemical composition of the two distillers byproducts is similar. Distillers byproducts contains 10-15% fat (oil), 40-45% neutral detergent fiber, 30-35% crude protein and 5% ash (NRC, 1996). Dried distillers byproduct is routinely fed as a supplemental protein source, however, the drying process appears to reduce the energy value of the distillers byproduct. Ham et al. (1994) demonstrated a 9% improvement in feed efficiency when dried distillers byproduct replaced 40% of the dry-rolled corn in finishing diets (Table 1). However, this improvement was only 50% of that observed when wet distillers byproduct replaced a similar amount of dry-rolled corn. Drying cost significantly increases the commodity price for the distillers byproduct. The dried distillers byproduct is routinely priced relative to other supplemental protein sources like soybean meal. Therefore, when priced on an energy basis (relative to corn), the expected improvement in animal performance is not large enough to offset the increased ration cost associated with higher inclusion levels. Wet distillers byproducts are commonly fed at higher levels in the diet to supply both protein and energy to the animal. There are numerous advantages to using wet distillers byproducts. For the dry-milling plant, the energy cost associated with drying the product can be significantly reduced or eliminated. This should allow for an overall increased energy yield for each bushel of corn processed. The major downside of using wet distillers byproducts is transportation costs associated with the movement of water. Experiments evaluating the use of wet distillers byproducts in ruminant diets are available (DeHaan et al, 1983; Farlin,1983; Firkins et al.,1985; Ham et al.,1994; Fanning et al.,1999; Larson et al., 1993; Lodge et al.,1997; Trenkle,1997a; Trenkle,1997b). In the experiments with finishing cattle, the replacement of corn grain with wet distillers byproduct consistently improved feed efficiency. Larson et al. (1993) replaced dry-rolled corn with 5.2,12.6 or 40% (dry matter basis) wet distillers byproduct (Table 2). With the first two levels of byproduct (5.2 and 12.6), these researchers observed a 7% increase in feed efficiency above the basal dry-rolled corn diet. But, when the inclusion level was increased to 40% of the diet dry matter, the improvement in feed efficiency was 20% above the dry-rolled corn diet. In other published experiments (Ham et al., 1994; Fanning et al., 1999; Lodge et al., 1997) the inclusion level of the wet distillers byproduct has been 30 to 40% of the diet dry matter. These experiments consistently suggest a 15 to 25% improvement in feed efficiency when 30 to 40% of the corn gain is replaced with wet distillers byproduct. 1

26 Distillers grains made from sorghum and corn were compared at 30% of the diet dry matter. Statistically the byproducts had similar feeding values (Table 3) although the corn derived grains were numerically, slightly better. Eleven experiments were summarized where WDB was compared to corn as an energy source for finishing cattle (Table 4). The WDB replaced 12.6 to 50% of the diet (corn). The data were summarized into three situations. First is the control diet based on dry rolled corn. Second is when WDB replaced corn at a low level in the diet (12.6 to 28%). The third situation is where WDB replaced corn in the diet at 30 to 50% of diet dry matter. At the low level (ave. 17.4%) of WDB feeding, the energy value was 152% that of corn. At the high level of feeding, the value decreased to 136% the value of corn. We can then calculate the value of the WDB as 124% the value of corn when fed between 17.4 and 40% of the diet. We believe there are very good explanations for the change in relative feeding values as WDB increases in the diet. We believe the first increments fed (up to 17.4%), supply nutrients such as protein that may be of value to the cattle but more importantly reduce the acidosis that occurs in the control diet. The WDB contains protein and fat which supply energy to the animal but it does not contain the starch that leads to acidosis. Further, the fiber (hull) in the WDB is highly digestible but adds fiber to the diet and reduces acidosis. So the very high value of the WDB (152%) at low level feeding is probably due to factors other than the strict energy value of the nutrients contained therein. The value when fed above 17.4% of the diet is probably due to the high fat content of the WDB and the high content of bypass protein. Fat has about three times the energy value of starch for cattle and bypass protein has about 30% more energy than starch. The value from feeding trials was determined to be 124% the value of corn. By calculating the theoretical energy value based on the bypass protein and fat contents, we estimate the energy value of WDB to be 120% the value of corn. This calculation gives confidence in the value obtained from feeding trials. Typical feedlot diets contain about 85% corn. The starch in the corn is the energy source used by the cattle. However, the starch is rapidly fermented by the rumen microorganisms to organic acids. The overproduction of the organic acids causes acidosis followed by reduced feed intake and reduced gains (Stock and Britton, 1993; Stock et al., 1995). Distillers byproducts have essentially all of the starch removed leaving protein, highly digestible fiber and fat. The feeding of the byproducts appears to reduce acidosis and enhances feed efficiency. The previous research indicates that wet corn byproducts (distillers grains and thin stillage) are higher in net energy than corn grain; however, wet corn gluten feed (WCGF) is similar in net energy to corn. Potential differences between wet distillers byproducts and WCGF include lipid content, escape protein level, and NDF level. A finishing trial using 60 individually fed yearling crossbred steers (600 lb) was conducted. Treatments consisted of a dry rolled corn, WCGF, wet distillers byproducts composite (COMP2), (WCGF, corn gluten meal, tallow), COMP2 minus tallow (-FAT) and COMP2 minus corn gluten 2

27 meal (-CGM). The tallow and corn gluten meal were replaced with wet corn gluten feed. The COMP2 was formulated (DM basis) to contain 12.5% degradable protein, 12.5% undegradable protein, 13.1 % lipid, and 32.7% NDF and consisted of 65.8% WCGF, 26.3 % CGM, and 7.9% tallow (DM basis). All diets contained (DM basis) 79.1 % dry rolled corn or dry rolled corn plus 40% corn byproducts, 5% corn silage, 5% alfalfa, 5.9% molasses based supplement, and 5% dry supplement. Steers consuming the COMP2, -CGM, and dry rolled corn diets were more efficient (P<.10) than the steers fed dry rolled corn or WCGF diets (Table 4). No difference in ADG was observed among treatments (P>.10). Steers fed the COMP2 diet consumed less (P<.10) feed than steers fed the dry rolled corn diet with the steers fed WCGF, -FAT, and -CGM being intermediate (P>.10) to these treatments. A composite of feeds can be formulated that improves efficiency of gain compared with WCGF. However, it is not clear what level of fat, fiber, or escape protein or how the interactions of these ingredients may contribute to the increases in feeding value observed with distillers byproducts. These results indicate that the lipid fraction of the distillers byproducts may be responsible for the largest increase in efficiency. There are at least three factors involved in the higher feeding value for distillers byproducts (protein, energy, acidosis). Based on the limited data available regarding the level of wet distillers byproduct in the diet, the economic value of the byproduct varies as the level fed in the diet changes. Also, as the level fed increases, more is fed per animal per day and more total byproduct would be fed. The precise relationship between level of byproduct in the diet and both the feeding value and economic value remains elusive. Distillers Grains for Stocker Cattle, Heifers and Cows Beef calves from weaning until they enter feedlots, developing heifers and beef cows are fed primarily forage diets. Especially in the winter, forages are low in protein and phosphorus and need to be supplemented. Further, the protein in forages is highly degraded in the rumen and the cattle should be supplemented with undegraded (bypass) protein to meet metabolizable protein requirements. Distillers grains (wet or dry) is an excellent source of undegraded protein and phosphorus. The values obtained from feeding trials for undegraded protein are shown in Table 5. Wet grains were compared to dry grains and the value of the protein was similar (Table 6). This suggests that the high escape protein value of distillers grains is due to the innate characteristics of the protein and not to drying or moisture control. Stocker calves, developing heifers and cows may need energy supplement in addition to supplemental protein and phosphorus. It is advantageous if the same commodity can be used for supplemental energy as well as protein. We previously stated that distillers grains should have 120% the energy value of corn grain. For example, corn at $2/bu is $79/ton (90% dry matter). That means dried distillers grains would be worth at least $95/ton as an energy source. Additional advantages for distillers grains are that it contains very little starch and therefore should not depress fiber digestion. 3

28 The value of distillers grains as a protein supplement is illustrated in Table 7. We have shown the formulation and cost of a soybean meal based supplement and a distillers grains based supplement. They should have equal feeding value but the distillers grains supplement is less expensive because of the high escape value of the protein. Less expensive midds and urea can then be used in the supplement. This illustrates just how economical distillers grains can be as a supplement to stockers, heifers and cows. Literature Cited DeHann, K., T. Klopfenstein, R. Stock, S. Abrams and R. Britton Wet distillers byproducts for growing ruminants. Nebraska Beef Rep. MP-43:33. Farlin, S.D Wet distillers grains for finishing cattle. Amin. Nutr. Health 36:35. Firkins, J.L., L.L. Berger and G.C. Fahey, Jr Evaluation of wet and dry distillers grains and wet and dry corn gluten feeds for ruminants. J. Anim. Sci. 60:847. Ham, G.A., R.A. Stock, T.J. Klopfenstein, E.M. Larson, D.H. Shain and R.P. Huffman Wet corn distillers byproducts compared with dried corn distillers grains with solubles as a source of protein and energy for ruminant. J. Anim. Sci. 72:3246. Fanning, K, T. Milton, T. Klopfenstein and M. Klemesrud Corn and sorghum distillers grains for finishing cattle. Nebraska Beef Rep. MP-71-A:32. Larson, E.M., R.A. Stock, T.J. Klopfenstein, M.H. Sindt and R.P. Huffman Feeding value of wet distillers byproducts from finishing ruminants. J. Anim. Sci. 71:2228. Lodge, S.L., R.A. Stock, T.J. Klopfenstein, D.H. Shain and D.W. Herold Evaluation of corn and sorghum distillers byproducts. J. Anim. Sci. 75:37. NRC Nutrient Requirements of Beef Cattle (7 th Ed.). National Academy Press, Washington, DC. Stock, R.A. and R.A. Britton Acidosis in Feedlot Cattle. In: Scientific Update on Rumensin/Tylan for the Profession Feedlot Consultant. Elanco Animal Health, Indianapolis, IN. p A-1. Stock, R.A., T.J. Klopfenstein and D. Shain Feed intake variation. In: Symposium; Intake by Feedlot Cattle. Oklahoma Agri. Exp. Sta. P-942:56. Trenkle, A., 1997a. Evaluation of wet distillers grains in finishing diets for yearling steers. Beef Research Report - Iowa State Univ. ASRI 450. Trenkle, A.1997b. Substituting wet distillers grains or condensed solubles for corn grain in finishing diets for yearling heifers. Beef Research Report - Iowa State Univ. ASRI

29 Table 1. Energy Value of Wet vs Dry Grains Control Wet Low a Medium a High a Daily feed, lb 24.2 b bc b 25.3 c 25.0 a 25.9 a Daily gain, lb 3.23 b 3.71 c 3.66 c 3.71 c 3.76 c Feed/gain 7.69 b 6.33 c 6.94 d 6.76 d 6.90 d Improvement: Diet (ave.) Distillers vs corn a Level of ADIN, 9.7, 17.5 and 28.8%. b,c,d Means in same row with different superscripts differ (P<.05). 5

30 Table 2. Effect of Wet Distillers Byproduct Level on Finishing Performance of Yearlings and Calves Byproduct level, % of diet DM a Item Daily feed, lb Yearlings b CalveS b Daily gain, lb Yearlings c Calves b Feed/gain Yearlings e Calves b a Wet grains:thin stillage (fed ratio), yearlings = 1.67:1; calves = 1.81:1, DM basis. b Byproduct level, linear (P<.O1). c Byproduct level, linear (P<.10); quadratic (P<.10). d Feed/gain analyzed as gain/feed. Feed/gain is reciprocal of gain/feed. e Byproduct level, linear (P<.10). Table 3. Corn vs Sorghum Distillers Byproducts Diets a Item DRC CORN SORG Initial weight, lb DMI, lb/day ADG, lb Feed/gain Yield grade Choice a DRC = dry-rolled corn (control), CORN = corn distillers grains, SORG = sorghum distillers grains. 6

31 Table 4. Influence of Level in Diet on Value of Wet Grains Plus Solubles in Feedlot Diets WDB level in diet dry matter Experiment % 30-50% Trenkle, 1997a.154a.183 (20)a.176 (40) 194% c 137% Trenkle, 1997a (40) 136% Trenkle, 1997b (16).168 (40) 126% 102% Trenkle, 1997b (28) 114% Firkins et al., (25).171 (50) 101% 121% Larson et al., (12.6).173 (40) 177% 150% Larson et al., (12.6).177 (40) 164% 135% Ham et al., (40) 147% Fanning et al., (30) 147% Means 152% (17.4) 136% (40) Value 17.4 to % a Feed efficiency b Level in diet dry matter. c Value relative to corn. 7

32 Table 5. Escape Protein Values Source % protein escape Soybean meal 30 Wet distillers grains Dried distillers grains Distillers solubles 30 Table 6. Wet and Dry Grains for Calves Supplement ADG Protein efficency a ADIN b Urea WG DDGS DDGS DDGS a Pounds gain/lb supplemental protein. b Acid detergent insoluble nitrogen, measure of amount of heating. Table 7. Value of Distillers Grains - 40% Supplement SBM DDG SBM % -- DG - 60% Midds Urea Minerals Ingredient cost $153 $95 Prices: SBM, $161; DDG, $95; Midds, $61; Urea, $280 (corn $75). 8

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36 Summary of Distillers Grains Feeding Recommendations for Dairy Cows and Dairy-Beef We recommend feeding a maximum of about 20% of total ration dry matter as distillers grains. This means 10 to 13 lbs. per cow daily of DDG or 30 or 40 lbs. per day of WDG for most lactating cows. Dr. David Schingoethe, Distillers Grains for Dairy Cattle, South Dakota State University Extension Service Extension Extra, ExEx 4022, August 2004 Distillers grains are a palatable, high energy, fiber feed and a good source of UIP for use in feeding dairy cows. DDGS or DDG can comprise up to 26% of the dietary DM fed to dairy cows. Dr. James G. Linn, University of Minnesota, and Dr. Larry Chase, Cornell University, Using Distillers Grains in Dairy Cattle Rations, Professional Dairy Conference Proceedings, 1996 Commonly, distillers grains and corn gluten feed are fed at 20% of the dietary dry matter, but recent research indicates that substantially more can in fact be fed, especially for CGF. Maximizing the use of these corn coproducts in ruminant diets will become increasingly important as more ethanol plants are built in the near future. Dr. Terry Klopfenstein, University of Nebraska-Lincoln, Uses of Corn Coproducts in Beef and Dairy Rations, Minnesota Corn Growers Technical Symposium Proceedings, 2002 Recent research results from Iowa State University have shown that 10, 20 or 40% of the ration dry matter as dry distillers grains with solubles could be fed to growing Holstein steers from 425 to 700 lbs. without affecting feed intake or gain. Feeding 10, 20 or 40% dry distillers grains or 10 and 20% wet distillers grains did not affect carcass weight, marbling or yield grades. Dr. Allen Trenkle, Iowa State University, The Advantages of Using Corn Distillers Dried Grains with Solubles in Dairy Beef Diets (Iowa Corn Growers Association brochure), 2004 Dairy-beef steers should be fed DG at % of the diet for optimum performance, carcass composition and profit margins Optimizing the use of distillers grains is becoming increasingly important as ethanol production increases. Dairy-beef production is a system that has potential to use large amounts of DG. C.B. Rinker and L.L. Berger, Optimizing the Use of Distiller Grain for Dairy-Beef Production, University of Illinois, 2003 The National Corn Growers Association provides these feeding recommendations to assist producers in understanding generally-accepted feeding levels. However, all rations for specific herds should be formulated by a qualified nutritionist. Moreover, the NCGA has no control over the nutritional content of any specific product which may be selected for feeding. Producers should consult an appropriate nutritionist for specific recommendations. NCGA makes no warranties that these recommendations are suitable for any particular herd or for any particular animal. The NCGA disclaims any liability for itself or its members for any problems encountered in the use of these recommendations. By reviewing this material, producers agree to these limitations and waive any claims against NCGA for liability arising out of this material.

37 The Advantages of Using Corn Distillers Dried Grains with Solubles in Dairy Diets An economical addition to dairy diets A very good protein and energy source for dairy rations The protein in new generation distillers grains: - More than 30% of dry matter - A good source of ruminally undegradable (bypass) protein - A good quality protein although lysine is the first limiting amino acid - Production by dairy cows fed distillers grains as the protein supplement is as high as or higher than when fed soybean meal The energy in new generation distillers grains: - 10 to 15% higher than previously reported for distillers grains - More energy per pound than in corn - Replacing the starch in corn with the highly digestible fiber and fat in distillers grains may decrease digestive upsets Recommend feeding a maximum of ~ 20% of ration dry matter as distillers grains - Can usually formulate nutritionally balanced diets - At more than 20-25% of ration dry matter: a) May decrease DM intake, especially if wet distillers grains b) May decrease milk production when fed in high amounts c) May feed excess protein and possibly excess phosphorus Wet versus dried distillers grains: - Nutrient content is the same for both - Storage and handling are considerations with wet distillers grains New considerations with feeding wet distillers grains: - Can store in silo bags for extended periods of time - Can blend with soyhulls, beet pulp, or corn silage Considerations when selecting suppliers of distillers grains: - Uniform nutrient content and quality - Watch for evidence of heat damage - Modified distillers grains may have certain fractions blended back into distillers grains. One needs to be aware of the nutrient content of such products so that total rations can be properly formulated using the modified distillers grains. Such products may actually be a higher value product to the producer, but one also wants a consistent product from one batch to the next. For additional information on feeding distillers grains to dairy cattle contact: Dr. David Schingoethe Dairy Science Department South Dakota State University Brookings, SD /19/2004

38 Extension Extra ExEx 4022 August 2002 Dairy Science COLLEGE OF AGRICULTURE & BIOLOGICAL SCIENCES / SOUTH DAKOTA STATE UNIVERSITY / USDA Distillers Grains for Dairy Cattle D.J. Schingoethe, K.F. Kalscheur, and A.D. Garcia Dairy Science Department Feeding distillers grains is nothing new; such products have been fed to cattle for more than a century. What is new, however, are the many ethanol plants now in the upper Midwest and the increased interest in feeding their co-product, distillers grains. This report is an overview of the nutritional value of distillers grains and gives some guidelines for feeding. Nutrient composition Distillers grains available today contain more protein and energy than those produced a number of years ago. For instance, most distillers grains available in the upper Midwest today contain 30% or more protein, more than the old book values of 23 to 26%. Today s distillers grains are a good source of protein and energy for dairy rations (Table 1). Protein content is similar for both distillers grains and distillers grains plus solubles (DDGS). Distillers grains are a good source of ruminally undegradable protein (RUP), with the RUP value being slightly less for wet (WDG) than for dried distillers grains (DDG). The protein in distillers grains is fairly good quality; lysine is its first limiting amino acid, a situation typical for all corn products. As for energy, research at SDSU demonstrates that today s distillers grains contain about 10% more energy (NEL = 1.0 Mcal/lb) than the old book values and that distillers grains contain more energy than corn. The product contains approximately 10% fat and a lot of readily digestible fiber. Distillers grains especially DDGS is a good source of phosphorus, an advantage or disadvantage depending on phosphorus needs in the diets. Distillers solubles or syrup contain more than 1% phosphorus compared to less than 0.83% phosphorus in the dry material of DDG. Most DDG have the solubles added, making it DDGS. WDG are usually but not always without solubles. Production response when fed distillers grains Research at SDSU and elsewhere shows that production, when distillers grains are in the ration, is the same as or greater than when soybean meal is the protein supplement. Production did not always increase when distillers grains diets were supplemented with ruminally protected lysine and methionine. Table 1. Composition of distillers grains Item % of DM Crude protein RUP 1, % of CP NEL, Mcal/lb 1.0 Fat Acid detergent fiber Neutral detergent fiber Calcium Phosphorus Ruminally undegradable protein We obtained the same milk production from cows fed distillers grains as the supplemental protein as when they were fed a blend of soybean meal, fish meal, and distillers grains. Condensed corn distillers solubles can also be fed directly to cattle even though the distillers solubles are often blended with distillers grains as DDGS. SDSU research demonstrated increased milk production when cows were fed 5% of the diet dry matter as condensed distillers solubles. Thus, distillers grains are a good quality protein supplement which cannot be readily improved. Wet vs. Dried Distillers Grains The nutrient content of the dry matter is similar for both WDG and DDG. Thus, cost, availability, feed handling,

39 and other factors may determine whether you feed wet or dried products. DDG can be stored for long periods of time. WDG can usually be stored only 5 to 7 days without experiencing some spoilage. Scientists at SDSU and elsewhere are working to extend the shelf life of WDG by ensiling, adding preservatives, or blending with other feeds such as soy hulls. Because WDG are only 30 to 35% dry matter, economical hauling distances are less than for DDG. The high water content may also limit total dry matter intake and milk production, especially if ensiled forages are also fed. Aim for a total ration dry matter at 50% or higher. At least one of the newer ethanol plants in South Dakota is offering a 50% dry matter distillers grains product by blending distillers solubles with DDG. How Much Distillers Grains Can be Fed? We recommend feeding a maximum of 20% of the total ration dry matter as distillers grains. This means 10 to 13 lb per cow daily of DDG or 30 to 40 lb per day of WDG for most lactating cows. At this 20% level, you can usually formulate nutritionally balanced diets in a variety of forage programs and not limit feed intake. In fact, distillers grains may be the only supplemental protein needed with a 50:50 blend of alfalfa and corn silage as the forages. At 30% or more of ration dry matter as distillers grains, total dry matter intake may be decreased, especially if feeding WDG. At this level, the diet would likely contain excess protein if legumes are in the diet. If the forages are mostly corn silage, you may be able to go up to 30% or more of the ration dry matter as DDG, but additional ruminally degradable protein and lysine may be needed and you will need to prevent excessive amounts of dietary phosphorus for good environmental nutrient management. Beef cattle have been fed as much as 40% of the ration dry matter in Nebraska research, but dry matter intake decreased at more than 30% of ration dry matter, especially with WDG. Such diets, particularly the DDGS, supplied excessive amounts of protein and excessive phosphorus. However, feedlot cattle experienced fewer cases of acidosis, laminitis, and liver abscesses when fed high distillers grains diets instead of high corn diets. This was likely because the ruminal fermentation of the fiber in distillers grains maintains a better rumen environment than does fermentation of the starch in corn and other grains. Distillers grains may also provide some protection against acidosis for dairy cows, although research data are not available to prove that. Distillers Grains for Growing Heifers Distillers grains can be used as a protein and energy source in diets for replacement heifers. Fifteen percent or less of the ration dry matter will often supply their protein needs. WDG are not recommended for calves less than 6 months old, primarily because the high water content of the co-product may limit dry matter intake. Distillers grains are appropriate to feed to growing heifers when needed and priced right, but growing heifers will need smaller amounts than you would feed to lactating cows or feedlot steers. Combining Distillers Grains with Other Byproducts Distillers grains, either wet or dry, can be combined with other feedstuffs to increase their nutrient content. SDSU research has shown that WDG can be preserved by ensiling alone or in combination with soy hulls. Soy hulls were combined with WDG at 0, 15, and 30% of the total weight and ensiled. The ph increased from 3.2 in WDG alone to 4.3 when soy hulls were blended with WDG in the 30% treatment. It has to be pointed out, however, that WDG has an intrinsically initial low ph (less than 3.7) due to the processing at the ethanol plant and not as a result of fermentation in the silo. The 70:30 WDG:SH blend was further field tested in silo bags. Conservation was good when it was fed out daily. Acceptability of the new feed by dairy cattle was excellent. The feasibility of pelleting DDG is also currently under study at SDSU. Pelleting offers the advantage of less feed wastage, as well as decreased transportation cost. Although straight DDG will not pellet due to high fat content, when soy hulls were included on a 50:50 mix by weight, the consistency of the pellets was adequate. The analysis of the DDG:SH pellets on a dry matter basis was 21.6% crude protein, 7.7% crude fat, 29.2% acid detergent fiber, and 42.1% neutral detergent fiber. This publication can be accessed electronically from the SDSU College of Agriculture & Biological Sciences publications page at or from the Extension Service Drought Information Website at Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the USDA. Larry Tidemann, Director of Extension, Associate Dean, College of Agriculture & Biological Sciences, South Dakota State University, Brookings. SDSU is an Affirmative Action/Equal Opportunity Employer (Male/Female) and offers all benefits, services, and educational and employment opportunities without regard for ancestry, age, race, citizenship, color, creed, religion, gender, disability, national origin, sexual preference, or Vietnam Era veteran status. ExEx4022: 150 copies printed by CES at a cost of 6 cents each. August 2002.

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41 Distillers Grains for Dairy Cattle 1 Dr. David J. Schingoethe 2 Dairy Science Department South Dakota State University The feeding of distillers grains to dairy cattle is nothing new; such products have been fed cattle for more than a century. The research article by Loosli et al. (1952) referenced an 1895 Vermont Agricultural Experiment Station Bulletin that reported on the feeding of distillers grains to lactating cows. In many respects, one might say that responses to feeding distillers grains today should be similar to those older studies. That may be correct except for some differences in both distillers grains and cows today versus yesterday. The distillers grains are different today, primarily containing more protein and energy, and today s cows produce much more milk than was produced by their ancestors. This presentation reports the results of recent studies in which distillers grains were fed to dairy cattle. While the emphasis of this presentation is on dried distillers grains, research conducted with both wet and dried products will be reviewed. Generally, one is referring to corn distillers grains (CDG) because that is what most of the studies in recent years have used; results with distillers grains from other grains would likely be similar. In most cases, the CDG used is dried distillers grains plus solubles (DDGS). The composition of CDG today, especially products coming from the new generation ethanol plants in the Midwest, contain more protein and energy than older book values. For instance, the CDG, both wet and dried, that was used in our SDSU research contained 30 to 36% or more crude protein on a dry matter (DM) basis versus the 23% CP for CDG and 25% CP for DDGS values reported in the 1989 nutrient requirements of dairy cattle (NRC, 1989). The new dairy NRC (2001) lists 29.7% CP for DDGS, a number that is closer to reality. The net energy for lactation (NE L ) in today s CDG is about 10% higher (~ 1.03 Mcal/lb) than the 0.90 Mcal/lb reported in NRC (1989; 2001). Contents of fat (10% or more), neutral detergent fiber (~ 39%), and acid detergent fiber (~ 19%) are only slightly different from the NRC values. Improved efficiencies in fermenting more of the starch that was in the corn to ethanol is likely the reason for these observed changes in the composition of CDG. Another nutritional consideration when feeding distillers grains or many other coproduct feeds is the phosphorus content. Dried CDG contains approximately 0.43% P and DDGS contains approximately 0.83% P, reflecting the high P content (1.37%) of distillers solubles. This high P content can be an advantage because it can allow one to decrease the amount of supplemental P normally added to the diet. Or, it can be a disadvantage if nutrient management concerns about high P content of manure can t be avoided by decreasing amounts of P from other feed sources. 1 Presented at Iowa Regional Distillers Grains Workshops, Calmar, Waverly, and Cherokee, IA, February Other researchers contributing to SDSU dairy distillers grains research include Drs. A.R. Hippen, K.F. Kalscheur and A.D. Garcia.

42 2 Protein in Corn Distillers Grains Corn distillers grains is a good source of ruminally undegradable protein (RUP). The reported values of 55% of CP as RUP is probably an appropriate figure to use in most cases. Most reported values range from 47% to 57% RUP although we obtained somewhat higher values (Brouk et al., 1994). One often assumes that wet CDG has lower concentrations of RUP than does dried CDG, but the differences are slight. Firkins et al. (1984) reported 47% RUP for wet CDG and 54% RUP for the dried product, which probably represents a realistic difference in RUP for the wet versus the dried products. Most of the readily degradable proteins in corn have been degraded during the fermentation process, so the protein remaining in the CDG is going to be proportionately higher in RUP than in the original corn. However, if RUP values for dried CDG are quite high (e.g. > 80% of CP), it may be advisable to check for heat damaged, undigestible protein. The quality of protein in CDG is fairly good. As with most corn products, lysine is the first limiting amino acid in CDG for lactating cows. More will be said about protein quality below in discussions about production responses to CDG. Production Response When Fed Corn Distillers Grains Table 1 summarizes milk production from several experiments in which cows were fed CDG. In experiments that compared CDG to soybean meal as the protein supplement, production was similar (Schingoethe et al., 1983; 1999) when fed wet CDG or higher (Nichols et al., 1998) when fed dried CDG than when fed soybean meal. With DDGS, production was similar to with soybean meal in a Nebraska study (Owen and Larson, 1991) and in a Florida study (Powers et al., 1995) in which the DDGS was dark and possibly heat damaged. When fed lighter colored DDGS from whiskey or from fuel-ethanol preparations, production was higher (P < 0.05) than when fed soybean meal (Powers et al., 1995). Some ethanol plants are striving to consistently produce improved quality DDGS products. Several experiments evaluated the protein quality of CDG and how additional protein or amino acid supplementation can be used to improve productivity of lactating cows. In the trial by Nichols et al. (1998), production increased when cows were fed ruminally protected lysine and methionine (RPLM). Wisconsin researchers (L. Armentano et al., 1997, unpublished results) observed similar increases with lysine supplementation. This response was expected because the protein in diets based on corn products are typically limiting in lysine. The greater production with CDG-based diets than with soybean-based diets was impressive but not entirely expected based on previous research with other corn-based products such as corn gluten meal. A multi-university study (Polan et al., 1991) observed lower production when fed corn gluten meal in place of soybean meal, even when the corn gluten meal was supplemented with RPLM. However, when one has obtained good results in an experiment, one shouldn t repeat it. The next step in our efforts to improve the quality of protein in diets of cows was to compare CDG as the only protein supplement to a blend of proteins that included CDG (Liu et al., 2000); both diets were fed with or without RPLM. Supplemental proteins fed in the BLEND diet were 25% from CDG, 25% from fish meal, and 50% from soybean meal. Theoretical evaluations of these diets (Schingoethe, 1996; O Connor et al., 1993) indicated that the BLEND diet contained

43 3 a more desirable array of amino acids and should have supported greater production than the CDG diet. However, this time there was no additional production when the CDG diet was supplemented with RPLM. Also, production was not significantly higher when fed a blend of several high quality protein supplements instead of CDG as the only protein supplement. The above studies illustrate that CDG is a good quality protein source and that it cannot be easily improved upon. Corn distillers grains can be easily used as the only source of supplemental protein in many dietary situations. Energy in Corn Distillers Grains Some speculated that the CDG available today might contain more energy than indicated by the book values. Therefore, we (Birkelo et al., 1994) conducted an experiment to determine the energy value of wet CDG for lactating cows. The research indicated that the digestible energy (DE), metabolizable energy (ME), and net energy for lactation (NE L ) of wet CDG were 1.86, 1.52, and 1.03 Mcal/lb DM, respectively. These values are 10 to 15% higher than published in the dairy NRC (2001) for DDGS. This likely reflects a higher energy value for newer generation distillers grains and does not necessarily reflect higher energy in wet than in dried CDG; that would have to be a separate comparison which has not been made. Wet versus Dried Distillers Grains One of the objectives of this presentation is to provide information about DDGS, but so far the presentation has contained information almost interchangeably about both wet and dried distillers grains. That is because the nutrient content of the dry matter is essentially the same for both wet and dried CDG except for possibly slightly lower RUP values for wet than for dried CDG (Firkins et al., 1984). I am not aware of any trials with lactating cows that directly compared wet versus dried CDG. The minimal amount of data comparing wet versus dried CDG with beef cattle would indicate that animal performance when fed wet CDG is just as good as or slightly better than when fed dried CDG. Likewise, I am not aware of direct comparisons between distillers grains versus distillers grains plus solubles. Again, I would expect similar animal performance with both products. The main considerations between the uses of wet versus dried CDG are handling and costs. Dried products can be stored for extended periods of time, can be shipped greater distances more economically and conveniently than wet CDG, and can be easily blended with other dietary ingredients. However, feeding wet CDG avoids the costs of drying the product. There are several factors to consider when feeding wet CDG that are not concerns when feeding DDGS. First, the product will not remain fresh and palatable for extended periods of time; 5 to 7 days is the norm. This storage time span will vary somewhat with environmental temperature as products will spoil and become unpalatable more rapidly in hot weather, but may be kept in an acceptable form as long as 3 weeks under cool conditions. Surface molds occasionally occur thus, there is usually some feed lost; a problem that wouldn t be a consideration with dried CDG, or DDGS. The addition of preservatives such as propionic acid or other organic acids may extend the shelf life of wet CDG, but scientific journal publications that document such results are difficult to find. In recent research, we at SDSU (Kalscheur et al., 2002, 2003, 2004) successfully stored wet CDG for more than six months in silo bags. The

44 4 wet CDG was stored alone or blended with soyhulls (Kalscheur et al., 2002) or with corn silage (Kalscheur et al., 2003). Some field reports indicate successful preservation of wet distillers grains for more than a year in silo bags. How Much Distillers Grains can be Fed? I recommend that dairy producers feed up to a maximum of about 20% of ration DM as distillers grains. With typical feed intakes of lactating cows, this would be about 10 to 12 lb of dried CDG or 33 to 37 lb of wet CDG per cow daily. There are usually no palatability problems and one can usually formulate nutritionally balanced diets with up to that level of distillers grains in the diet. For instance, with diets containing 25% of the dry matter as corn silage, 25% as alfalfa hay, and 50% concentrate mix, the CDG can likely replace most if not all of the protein supplement such as soybean meal and a significant amount of the corn that would normally be in the grain mix. In diets that contain higher proportions of corn silage, even greater amounts of DDGS may be useable. However, the need for some other protein supplement, protein quality (e.g. lysine limitation), and P concentration may become factors to consider. In diets containing higher proportions of alfalfa, less DDGS may be needed to supply the protein required in the diet, and in fact the diet may not be able to utilize as much DDGS. When feeding more than 20% distillers grains, one is likely to feed excess protein, unless forages are all or mostly corn silage and/or grass hay. In previous research (Schingoethe et al., 1999) we fed slightly more than 30% of the ration DM as wet CDG with decreased DM intake but no decrease in milk production. However, recent research by our group (Hippen et al., 2003; 2004) in which as much as 40% of ration dry matter was fed as CDG indicated problems when the CDG provided more than 20 to 25% of the ration DM. With wet CDG (Hippen et al., 2003), DM intake decreased when diets contained more than 20% wet CDG with a corresponding decrease in milk production also. Gut fill may have limited DM intake of these wet diets because total DM intake may decrease when the diet is less than 50% DM, especially when fermented feeds are included in the diet (NRC, 2001). However, when dried CDG (DDGS) was fed, (Hippen et al., 2004) DM intake and milk production were still decreased when diets contained 27 or 40% dried CDG. Milk fat percentages also decreased when fed more than 13% DDGS. We don t know why that occurred because milk fat percentages were not adversely affected by distillers grains in our previous research (Liu et al., 2000; Nichols et al., 1998; Schingoethe et al., 1999) in which 20 to 30% distillers grains were fed. There may be fewer off-feed problems when feeding distillers grains than when feeding corn, based on research with beef cattle. That is because, even though the distillers grains contains similar amounts of energy as corn, the energy in distillers grains is primarily in the form of digestible fiber and fat; in corn most of the energy is as starch. Ruminal starch fermentation is more likely to result in acidosis, laminitis, and fatty liver. Distillers Grains Blended with Other Feeds Several experiments have been recently conducted at SDSU in which wet CDG was blended with other high fiber feeds. Such approaches may be helpful in times when forage supplies are limited or expensive. For instance, a 70:30 (DM basis) blend of wet CDG and

45 5 soyhulls reduced the dustiness of soyhulls, reduced the seepage that is common with wet CDG, provided more desirable protein (21% CP) and P (0.6%) contents, and yet provided a high energy, high fiber feed (Kalscheur et al., 2002). Growth rates of heifers fed the blend were similar (2.7 to 2.8 lb/d) to gains when fed conventional diets (Kalscheur et al., 2004). When heifers were fed a blend of wet CDG (69% of DM) and corn stalks (31%), weight gains were less (2.3 lb/d) than when fed conventional diets (2.8 lb/d). Ensiling wet CDG alone or in combination with corn silage indicated that preservation of each could be enhanced by combining the feedstuffs with a 50:50 blend likely optimal (Kalscheur et al., 2003). Other Corn Products as Feeds There are several other corn products such as corn gluten meal, corn gluten feed, and corn distillers solubles that can also be fed to dairy cattle. I won t spend a lot of time talking about corn gluten meal and corn gluten feed, except for a sentence or two about each, because they are not included in the major thrust of this presentation. Corn gluten meal is a high protein (60% CP) and high RUP (55% of CP) feed that is a very good protein supplement but is best fed in combination with other protein supplements (Polan et al., 1991). Corn gluten feed is a good overall feed that is medium in protein (25% of CP), low in RUP (25% of CP), a good energy source (NE L = 0.86 Mcal/lb), and sometimes priced competitively with other feed sources. Corn distillers solubles will be discussed more extensively because they are a part of the same process that produces CDG. Distillers solubles are usually blended in with the distillers grains before drying to produce DDGS, but the solubles may be fed separately also. We (DaCruz et al., 1996) conducted one experiment with lactating cows in which condensed corn distillers solubles (CCDS) were fed at 0, 5, and 10% of total ration DM. The CCDS contained 28% DM and that DM contained 18% CP, 21.5% ether extract (fat), 12.5% minerals, and approximately 0.91 Mcal NE/lb. Milk production (75.2, 78.3, and 78.9 lb/d for 0, 5, and 10% CCDS diets) increased when fed the CCDS. Milk fat percentages (3.54, 3.33, and 3.43) were slightly lower (P < 0.05) when fed CCDS while milk protein percentages (2.93, 2.97, 2.95) were unaffected by diets. The added energy from fat in the CCDS likely contributed to the increased milk production but may have also caused the observed slight milk fat depression. Dry matter intakes (54.7, 53.8, and 49.6 lb/d) were similar for control and CCDS diets, although intake tended (P < 0.10) to be lower when fed 10% rather than 5% CCDS. It was concluded that feeding CCDS at 5% of ration DM is effective and profitable for dairy producers. There was no additional advantage to feeding CCDS at 10% of ration DM. Conclusions Corn distillers grains is a good protein and energy feed to include in rations for dairy cattle. The nutrient content of the dry matter in CDG is essentially the same for both wet and dried CDG. Nutrient content is also similar whether or not the solubles are added to the distiller grains to make DDGS, with the exception of the higher P content with the solubles added. References cited Birkelo, C.P., M. J. Brouk, and D. J. Schingoethe The energy content of wet corn distillers grains for lactating dairy cows. J. Dairy Sci. 87:

46 6 Brouk, M. J., D. J. Schingoethe, and C. P. Birkelo In situ degradability of wet and dried corn distillers grains. J. Dairy Sci. 77 (Suppl. 1):135 (Abstr.) DaCruz, C. R., M. J. Brouk, and D. J. Schingoethe Utilization of condensed corn distillers solubles in lactating dairy cow diets. J. Dairy Sci. 88: Firkins, J. L., L. L. Berger, G. C. Fahey, Jr., and N. R. Merchen Ruminal nitrogen degradability and escape of wet and dry distillers grains and wet and dry corn gluten feed. J. Dairy Sci. 67: Hippen, A.R., K.N. Linke, K.F. Kalscheur, D.J. Schingoethe, and A.D. Garcia, Increased concentrations of wet corn distillers grains in dairy cow diets. J. Dairy Sci. 86(Suppl. 1):340 Abstr.) Hippen, A.R., K.F. Kalscheur, D.J. Schingoethe, and A.D. Garcia Increasing inclusion of dried corn distillers grains in dairy cow diets. J. Dairy Sci. 87:1965 (Abstr.) Kalscheur, K.F., A.D. Garcia, A.R. Hippen, and D.J. Schingoethe Ensiling wet corn distillers grains alone or in combination with soyhulls. J. Dairy Sci. 85(Suppl. 1):234 (Abstr.) Kalscheur, K.F., A.D. Garcia, A.R. Hippen, and D.J. Schingoethe Fermentation characteristics of ensiling wet corn distillers grains in combination with corn silage. J. Dairy Sci. 86(Suppl. 1):211 (Abstr.) Kalscheur, K.F., A.D. Garcia, A.R. Hippen, and D.J. Schingoethe Growth of dairy heifers fed wet corn distillers grains ensiled with other feeds. J. Dairy Sci. 87:1964 (Abstr.) Liu, C., D. J. Schingoethe, and G. A. Stegeman Corn distillers grains versus a blend of protein supplements with or without ruminally protected amino acids for lactating cows. J. Dairy Sci. 83: Loosli, J. K., K. L. Turk, and F. B. Morrison The value of distillers feeds for milk production. J. Dairy Sci. 35: National Research Council Nutrient Requirements of Dairy Cattle. 6th rev. ed. Natl. Acad. Sci., Washington, DC. National Research Council Nutrient Requirements of Dairy Cattle. 7th rev. ed. Natl. Acad. Sci., Washington, DC. Nichols, J. R., D. J. Schingoethe, H. A. Maiga, M. J. Brouk, and M. S. Piepenbrink Evaluation of corn distillers grains and ruminally protected lysine and methionine for lactating dairy cows. J. Dairy Sci. 81: O Connor, J. D., C. J. Sniffen, D. J. Fox, and W. Chalupa A net carbohydrate and protein system for evaluating cattle diets. IV. Predicting amino acid adequacy. J. Anim. Sci. 71:

47 7 Owen, F. G., and L. L. Larson Corn distillers dried grains versus soybean meal in lactation diets. J. Dairy Sci. 74: Powers, W. J., H. H. Van Horn, B. Harris, Jr., and C. J. Wilcox Effects of variable sources of distillers dried grains plus solubles or milk yield and composition. J. Dairy Sci. 78: Polan, C. E., K. A. Cummins, C. J. Sniffen, T. V. Muscato, J. L. Vincini, B. A. Crooker, J. H. Clark, D. G. Johnson, D. E. Otterby, B. Guillaume, L. D. Muller, G. A. Varga, R. A. Murray, and S. B. Pierce-Sandner Responses of dairy cows to supplemental rumen-protected forms of methionine and lysine. J. Dairy Sci. 74: Schingoethe, D. J Balancing amino acid needs of the dairy cow. Anim. Feed Sci. Technol. 60: Schingoethe, D. J., M. J. Brouk, and C. P. Birkelo Milk production and composition from cows fed wet corn distillers grains. J. Dairy Sci. 82: Schingoethe, D. J., A. K. Clark, and H. H. Voelker Wet corn distillers grains in lactating dairy cow rations. J. Dairy Sci. 66: Table 1. Milk production response to diets containing corn distillers grains as the supplemental protein source. Protein supplement SBM CDG BLEND Experiment SBM RPLM CDG +RPLM 1 BLEND +RPLM (milk, lb/d) Schingoethe et al., Schingoethe et al., Nichols et al., Liu et al., Owen & Larson, Powers et al., * Powers et al., * Powers et al., RPLM: ruminally protected lysine and methionine 2 BLEND: supplemental protein was approximately 25% from CDG, 25% from fish meal, and 50% from soybean meal (SBM). 3 Wet CDG 4 Dried CDG 5 Dried CDG plus solubles 6 Whiskey dried CDG plus solubles 7 Fuel-ethanol dried CDG plus solubles 8 Darker fuel-ethanol dried CDG plus solubles * Production was greater than with SBM, P < 0.05

48 USING DISTILLERS GRAINS IN DAIRY CATTLE RATIONS Dr. James G. Linn Department of Animal Science, University of Minnesota, St. Paul, MN and Dr. Larry Chase Department of Animal Science, Cornell University, Ithaca, NY Distillers grains are co-products produced from the fermentation of grains for alcohol. Traditionally, alcohol was produced mainly for the beverage liquor industry, but in the last 20 years its use as an alternative fuel has increased significantly. This increased demand has led to the development of several ethanol production plants in Minnesota and the surrounding area. In 1996, it is estimated 135,000 tons of distillers grains will be produced from current plants with production doubling or tripling over the next five years as more ethanol plants begin operation. Thus, the opportunity exists for using a substantial quantity of distillers grains in dairy rations. When grains are fermented to alcohol, approximately one-third of the dry matter (DM) is recovered in co-products. The two basic products at the end of the fermentation process are coarse, unfermented grains and a liquid fraction known as thin stillage containing small particles of grain, yeast and soluble nutrients. These two products are further processed into the following four co-products: 1) distillers dried grains (DDG), 2) distillers dried solubles (DDS), 3) distillers dried grains with solubles (DDGS), and 4) condensed distillers solubles, 30 to 40% DM (CDS). Both the CDS and DDS are made from thin stillage through partial (CDS) or complete (DDS) drying. Dried distillers grain with solubles is produced by adding a portion of the thin stillage back to the unfermented grain fraction at the time of drying. The two primary co-products used in the feed industry are DDG and DDGS. Alcohol can be produced from one or any combination of cereal grains. The most commonly used grains are corn, milo, wheat, barley and rye. The grain used in the largest quantity is used to name the resulting product. For example, corn distillers grains would be produced from a fermentation batch where corn was the primary grain used. As the names imply, most distillers grains are produced in a dry form. This results in ease of handling, storage and shipping to local or foreign markets. The effects of drying on nutrient availability have been of some concern and debated in various research studies. Wet distillers grains are available in some areas. This reduces the energy costs of drying but increases their perishability and handling problems for the feeder. Nutrient Composition The typical nutrient content of corn-based distillers grains is shown in Table 1. In general, distillers grains are devoid of starch but a good source of energy, protein, fiber and phosphorus. The nutrient content of distillers grains is about three times more concentrated than the nutrients in the original grain before fermenting. Yeast cells also are quite high in distillers grains (10). 1

49 The yeast species Sacchsromyces cerevisiae is commonly used for fermentation, as it is an efficient producer of alcohol. Yeast concentrations often reach 150 million cells per cubic centimeter in mashes after just 26 hours of fermentation. Table 1. Nutrient composition of common corn distillers co-products. 1 Nutrient 2 Distillers grains (DDG) Distillers grains + solubles (DDGS) Condensed distillers solubles (CDS) DM, % CP, % NE L, Mcal/lb TDN, % Fat, % ADF, % NDF, % NRC, 1989 (14). 2 All nutrients except DM expressed on a DM basis. The nutrient content of distillers grains can be influenced by a number of factors. The primary factors are the type of grain (Table 2), milling process, grain quality, fermentation process, drying temperature and amount of solubles blended back into the unfermented fraction at the time of drying. Chase (4) showed ranges in the DM content of DDGS as follows: crude protein (CP) - 22 to 33%, neutral detergent fiber (NDF) - 29 to 64%, and fat - 2 to 20%. Purchasers of distillers grains must be cognizant of variations in nutrient content. When purchasing distillers grains, it is important to know what grain or combination of grains were used in the fermentation. Distillers grains should be tested for DM, CP, acid detergent fiber (ADF), NDF, ADF insoluble nitrogen (ADIN) and fat. Of particular interest to dairy nutritionists is the undegradable intake protein (UIP) or bypass protein content. Values published by the NRC (14) for UIP of corn DDG and DDGS are 54 and 47% of the CP. More recent results have shown corn-based DDGS to vary from about 45% (17) to 55% (9). Stern et al. (20) analyzed five samples of distillers grains and found a UIP of 56+8% with an intestinal digestibility of the UIP at 81+5%. Grings et al. (9) reported the intestinal digestibility of UIP in DDGS was 93%. Soluble intake protein (SIP) of distillers grains was estimated by Chase (4) to be about 15% of the CP, but more recent research (17) has shown it to be about twice that value (28.5% of the CP). The amino acid profile of two corn and one milo DDGS is shown in Table 3. With today s emphasis on balancing amino acids in the diets of dairy cows, knowing the amino acid content and the variation that can occur in high bypass protein sources like DDGS is important. Dong et al. (16) evaluated the amino acid profiles of several wheat DDGS and found profiles in the DDGS to be similar to the whole grain before fermentation. 2

50 Table 2. Nutrient composition of some non-corn distillers dried grains with solubles (DDGS). 1 Nutrient Barley DDGS 2 Rye DDGS 3 Wheat DDGS 4 DM, % CP, % ADF, % NDF, % ADIN, % of CP All nutrients except DM expressed on a DM basis. 2 Weiss et al. (22). 3 Shelford and Tait (18). 4 Boila and Ingalls (3). Table 3. Amino acid profile of corn and milo distillers dried grains with solubles (DDGS). Amino acid Corn DDGS 1 Corn DDGS 2 Milo DDGS % of DM Lysine Methionine Histidine Arginine Threonine Leucine Isoleucine Valine Phenylalanine Tryptophan.20 1 Distillers Feed Research Council, Des Moines, IA. 2 Powers et al. (17). Grains are generally low in fiber and considered an insignificant fiber source in diets for dairy cattle. However, concentration of the fiber by removal of starch during fermentation results in DDG and DDGS being a very good source of nonforage fiber for dairy cattle. The NDF content of distillers grains is typically 35 to 40% of the DM (Table 1). However, the fiber is very short in particle length and, therefore, raises questions as to its effectiveness in stimulating cud chewing. The effective fiber values of nonforage fiber sources have been determined by either their physical characteristics and how they contribute to rumen mat formation and cud chewing or by 3

51 their ability to support a normal milk fat percentage when used to replace forage fiber in a diet (1, 8). Bhatti and Firkins (2) indicated the digestion of NDF in distillers grains is rather slow initially, but once initiated the digestion rate was relatively fast (.0626/hour). The slow initiation could be a reflection of the low water holding capacity (.062g/g of insoluble DM) of NDF in distillers grains, as fiber must be hydrated before digestion by bacteria (2). The slow initial digestion rate in combination with a small particle size can result in a fast rate of passage from the rumen. Thus, the physical effectiveness of NDF in distillers grains to stimulate cud chewing appears to be quite limited. The use of milk fat percentage as a measure for effective fiber is based on the digestion of fiber in the rumen and not the physical attributes needed for stimulation of cud chewing. Firkins (8) indicated the NDF in nonforage fiber sources like DDS or DDGS are less than half as effective as forage NDF sources in stimulating cud chewing. Thus, the effective fiber values for nonforage feeds based on milk fat percentage represents their ability to substitute for nonfiber carbohydrates (NFC) in diets rather than stimulate cud chewing. Using the milk fat percentage method, Clark and Armentano (5) determined DDG had an effective NDF value equal to that of alfalfa haylage. In comparison with corn silage NDF in maintaining milk fat percentage, Staples et al. (19) found DDGS NDF was 68% as effective. However, in diets high in corn silage and considerably above NRC minimum fiber recommendations the effectiveness of NDF in DDGS was negative. In other words, replacing corn and soybean meal with DDGS in diets high in NDF decreased milk fat percent. Evaluating Protein Quality Extensive heating of distillers grains during the drying process has raised questions about the nutrient availability, especially protein, in DDS and DDGS. The effects of excessive heating on reducing protein availability to animals has been well documented. Acid detergent insoluble nitrogen (ADIN) or the amount of nitrogen in the ADF fraction has been used as an indicator and measure of the protein availability reduction in a feed due to heat damage. Chase (4) extensively reviewed the use of ADIN as a method utilized to estimate heat damaged protein in distillers grains and other co-products. He concluded that ADIN, although not perfect, can be a good index for measuring heat damage in feeds. Nakamura et al. (13) found a range in ADIN from 7.8 to 27.9% of the total nitrogen in distillers grains from seven different distillers. A relationship between ADIN and bypass protein content of the distillers grains was evident (r 2 =.55); however, the correlation with true digestibility of nitrogen in distillers grains was very low (r 2 =.24). An average of 78% of the ADIN in the seven samples of distillers grains was digested by sheep. Additional research by Klopfenstein (11) suggested some of the nitrogen associated with ADIN can be absorbed from the digestive tract but may not be efficiently utilized by the animal for growth. The biological availability of amino acids such as lysine appears to be reduced during the heating process. Protein solubility is not a good estimator of ADIN content in distillers grains. Both Chase (4) and Powers et al. (17) demonstrated either a very poor or no correlation between ADIN and soluble protein, expressed as percent of CP, content in distillers grains. 4

52 An early biological indicator of heat damage in distillers grains may be a reduction in milk protein percentage when fed to lactating cows. Van Horn et al. (21) observed a reduction in milk protein percentage in cows fed DDGS with a high ADIN content (32.9% of the total nitrogen) compared to cows fed soybean meal. Others (15, 16) have observed similar results. However, it is unclear whether the reduction in milk protein percentage was caused solely from a high ADIN content in distillers grains or an imbalance of amino acids in these diets, namely low lysine, created by the substitution of distillers grains for soybean meal. When feeding diets containing both soybean meal and DDGS, Powers et al. (17) observed a slight decline in milk protein percentage only when the DDGS source contained more than 20% of the nitrogen in the ADIN fraction. There appears to be conclusive evidence that animal performance is diminished in some manner when heat damaged protein feeds are fed. The exact level of ADIN in DDG or DDGS where a depression in animal performance occurs is unknown. However, color of distillers grains appears to be associated with amount of ADIN (17). Good, high quality distillers grains will have a honey golden to caramelized golden color. Color progressing towards dark coffee grounds is an indicator of excessive heating during the drying process and the potential for high levels of ADIN. Research Studies with Distillers Grains Early research work on feeding distillers grains to dairy cattle has been summarized in a 1991 review by Chase (4). Performance results from these studies were inconsistent. In studies where increases in milk yield or milk components were found, the forage base of the diet was alfalfa or a mixture of alfalfa and corn silage. Decreases in milk production or milk components from feeding distillers grains were associated with high levels of ADIN in DDGS and with all or very high levels of corn silage in the diet. Current knowledge would indicate that the studies reporting lowered milk production resulted from reduced microbial growth in the rumen and a low dietary lysine content as the primary source of dietary protein was from corn products. Since 1991, five research studies evaluating the use of distillers grains in lactating dairy cow diets were found. These are summarized below and in Table 4. Owen and Larson (15) reported the results of a study comparing DDGS and soybean meal in diets for early lactation cows. The dietary DM fed in this study consisted of 50% ammoniated corn silage and 50% concentrate. Milk production of cows fed DDGS or soybean meal was equal when DDGS was included in the diet at 19% of the DM (low CP diet %) but decreased when DDGS was included at 36% of the DM (high CP diet - 18%). The authors concluded that the poor performance of cows fed the high DDGS diet was from poor digestibility and a shortage of available lysine. The decrease in milk protein percentage on both the high and low CP diets with feeding of DDGS compared to soybean meal also indicates available lysine was deficient in these corn based diets (Table 4). 5

53 The substitution of DDGS for ground corn in early lactation diets was evaluated by Grings et al. (9). The diets were alfalfa-based and contained 61% concentrate with DDGS at 0, 10.1, 20.8 and 31.5% of the dietary DM. Crude protein content of the diets increased with increasing DDGS amounts (13.9, 16.0, 18.1 and 20.3%). Milk yield and milk protein percentage increased linearly with increasing dietary CP (Table 4). Dry matter intakes were not different among the four treatments; however, fat and UIP intakes increased and NFC intakes decreased as DDGS in diets increased. The beneficial response to increasing CP in alfalfa-based diets up to 18.1% by the addition of DDGS was attributed to an increased intake of CP, UIP and essential amino acids. Intestinal availability of UIP in the DDGS fed in this study was determined to be 93%. Using a Latin square design with mid-lactation cows, Clark and Armentano (5) determined the effect of replacing alfalfa NDF with NDF from DDG on milk production and composition. Although this was only a short term study with objectives to measure fiber effectiveness, substituting DDG for 12.7% of the alfalfa DM in the diets resulted in both a milk production and milk protein percentage increase (Table 4). Powers et al. (17) compared the performance of mid- and early-lactation cows fed 14 or 18% CP diets containing DDGS from three different sources or soybean meal with and without blood meal. Amounts of DDGS in diets were 13% of the DM in the 14% CP diet and 26% of the DM in the 18% CP diet. The three sources of the DDGS are designated as 1, 2 and 3. All diets were a 50:50 forage to concentrate ratio (DM basis) with corn silage as the sole forage. The DDGS from sources 1 and 2 (DDGS-1 and DDGS-2) were lower in ADIN (13 and 17% of the CP, respectively) and lighter in color than the third source (DDGS-3) with 21% ADIN. Production results are shown in Table 4. Dry matter intakes were not affected by either source or amount of CP in the diet. Milk productions from cows fed either DDGS-1 or DDGS-2 were higher than those of cows fed soybean meal. Milk production of cows fed DDGS-3 was similar to cows fed soybean meal. Milk yields were higher with 26% DDGS than with 13% DDGS included in diets. Milk protein percentage was decreased with feeding DDGS-3. The authors indicated that quality differences in DDGS do affect animal performance and need to be considered when DDGS is fed. They concluded that color and ADIN content of DDGS along with milk protein percentage are good indicators of DDGS quality. Staples et al. (19) evaluated the effects of DDGS on the performance of dairy cows fed corn silage-based diets varying in concentrate to forage ratio. Three concentrate to forage ratios were fed (70:30, 55:45 or 40:60) with either 0 or 20% DDGS in the dietary DM. With increasing concentrate level in the diet, a linear increase in DM intake and milk production and a linear decrease in milk fat percentage was observed (Table 4). Feeding DDGS in replacement of corn and soybean meal resulted in about 2.5 lb more milk per day. The effectiveness of NDF in DDGS in elevating milk fat percentage when fiber deficient diets are fed was determined to be about 68% as effective as corn silage NDF. 6

54 Table 4. Distillers grains production trials. Production measures Reference CP Conc DDGS DM Milk Fat Protein % of diet DM lb/day % Base forage - Ammoniated corn silage Base forage - Alfalfa Base forage - Alfalfa Base forage - Corn silage (1) (2) (3) (1) (2) (3) Base forage - Corn silage Number in ( ) indicates source of DDGS (see text for explanation). Feeding Recommendations Distillers grains are a palatable, high energy, fiber feed and a good source of UIP for use in feeding dairy cows. Based on the research reviewed, DDGS or DDG can comprise up to 26% of the dietary DM fed to dairy cows. The basic limit as to the quantity of distillers grains that can be fed will be determined by the CP and UIP content of the diet. Because distillers grains are relatively high in UIP (55% of the CP), feeding high amounts of distillers grains can result in low 7

55 rumen ammonia levels and deficiency of DIP in the diet. Also, the profile of amino acids in the diet as well as those presented to the intestine must be considered when distillers grains are included in rations. Balancing diets for SIP, DIP and UIP along with consideration of CP, lysine and methionine can minimize many of the problems and negative effects observed with feeding distillers grains in research studies. In addition to the above, it is advisable to limit the amount of CP coming from corn sources in a ration to less than 60% of the total CP. Corn protein sources would include corn silage, corn grain, corn DDGS, corn gluten meal and corn gluten feed. The NDF in distillers grains is effective in maintaining milk fat percentage but is relatively ineffective at stimulating cud chewing. Therefore, distillers grains is an effective substitute for NFC in diets but has limited forage fiber replacement abilities. If the minimum amount of forage in the diet meets the physically effective fiber requirement for cud chewing, then distillers grains can be used to replace any additional forage fiber needed in the diet. The effective replacement rate of NDF in distillers grain for forage fiber is considered to be about 66%. Therefore, for every 1 lb of forage NDF needed in a diet, 1.5 lb of NDF from distillers grains must be added. Economic Considerations Several approaches are available to estimate the economic value of distillers grains as well as other feeds (7). In any pricing considerations, nutrient variability along with ease of handling and storage, overall feed quality and animal acceptance must be considered. The preferred method of pricing is a least-cost ration as this evaluates the use of all feeds under consideration for the diet under a well-defined set of nutrient requirements. However, in many situations a quick comparison of one feed against one or two other feeds based on protein and energy value is all that is desired. The following methods can be used to obtain a quick comparison of economical value for DDGS: 1. Price based on cost/unit of CP or UIP. $/unit of CP or UIP = $/unit of feed / (unit of feed x DM x CP or UIP) Example: Cost of CP from soybean meal (49.9% CP, DM basis; 89% DM) $/lb of CP = $250/ton / (2000 lb x.89 x.499) = $.28/lb of CP Cost of CP from DDGS (28% CP, DM basis; 92% DM) $/lb of CP = $150/ton / (2000 lb x.92 x.28) = $.29/lb of CP 8

56 Similar calculations can be made for UIP Example: DDGS (where UIP is 55% of CP) $/lb of UIP in DDGS = $150/ton / (2000 lb x.92 x.28 x.55) = $.53/lb of UIP 2. Equation to price DDGS in relation to corn (energy source) and soybean meal (CP source). All feeds must be priced on a common unit basis ($/cwt or $/ton) and on an equal DM basis such as air dry (90% DM). Corn = $7.14/cwt Soybean meal = $12.50/cwt $/cwt of DDGS = ($ of corn x.531) + ($/cwt of soybean meal x.514) = ($7.14 x.531) + $12.50 x 514) = $10.22/cwt or $204.40/ton 3. Another way of pricing DDGS based on protein and energy is against a mix of soybean meal, corn and fat which is equal in CP and energy to the DDGS. An example of a 100 lb mix equivalent to DDGS of 25% CP, 9% fat and 86 Mcal of NE L (as fed basis) is: lb/100 lb $/100 lb of mix x $/lb = of mix Soybean meal 47.5 x.1250 = 5.94 Corn 46.0 x.0714 = 3.28 Tallow 6.5 x.25 = 1.62 Total Feeding Wet Distillers Grains $10.84 / 100 lb of DDGS For some dairy producers, feeding wet distillers grains (WDG) directly from an alcohol plant may be an option. Very little information is available on feeding WDG, especially to dairy cattle. Klopfenstein and Stock (12) summarized several studies conducted by the authors on feeding WDG to feedlot cattle. Dry matter content of WDG averaged 31.4%. Nutrient composition of WDG is slightly different than DDG. The WDG fed in their research studies contained more starch and ethanol and less protein than typically found in DDG. The energy value for gain determined from feeding trials was 1.28 to 1.69 times greater for WDG than corn. No differences in protein efficiency were found between DDGS and WDG when fed to growing calves. As with any high moisture feed, the handling, storage, storage loss and transportation costs must be considered in the usage and economic value of WDG. 9

57 REFERENCES 1. Armentano, L Balancing carbohydrates for lactating cows: Impact of fiber source on amount of fiber in diet. Proc. 56th Minnesota Nutr. Conf. p Bhatti, S. A., and J. L. Firkins Kinetics of hydration and functional specific gravity of fibrous feed by-products. J. Anim. Sci. 73: Biola, R. J., and J. R. Ingalls The post-ruminal digestion of dry matter, nitrogen and amino acids in wheat based distillers dried grains and canola meal. Anim. Feed Sci. and Tech. 49: Chase, L. E Using distillers grains and hominy in dairy rations. Proc. Alternative Feeds for Dairy and Beef Cattle. p Clark, P. W., and L. E. Armentano Effectiveness of neutral detergent fiber in whole cottonseed and dried distillers grains compared to alfalfa haylage. J. Dairy Sci. 76: Dong, F. M., B. A. Rasco, and S. S. Gazzaz A protein quality assessment of wheat and corn distillers dried grains with solubles. Cereal Chem. 64: Eastridge, M. L Economic value of alternative feeds based on nutritive composition. Proc. 2nd National Alternative Feed Symp. p Firkins, J. L Fiber value of alternative feeds. Proc. 2nd Alternative Feeds Symp. p Grings, E. E., R. E. Roffler, and D. P. Deitelhoff Responses of dairy cows to addition of distillers dried grains with solubles in alfalfa-based diets. J. Dairy Sci. 75: Hatch, R. H Distillers grains, their production and nutritive value. Proc. Pacific NW Animal Nutr. Conf. p Klopfenstein, T. J Efficiency of escape protein utilization. Proc. Distillers Feed Conf. p Klopfenstein, T. J., and R. A. Stock Feeding wet distillers and gluten feed to ruminants. Proc. 53rd Minnesota Nutr. Conf. p Nakamura, T., T. J. Klopfenstein, and R. A. Britton Evaluation of acid detergent insoluble nitrogen as an indicator of protein quality in nonforage proteins. J. Anim. Sci. 72: National Research Council Nutrient requirements of dairy cattle. 6th Rev. Ed. National Academy of Science, Washington, D.C. 10

58 15. Owen, F. G., and L. L. Larson Corn distillers dried grains versus soybean meal in lactation diets. J. Dairy Sci. 74: Palmquist, D. L., and H. R. Conrad Utilization of distillers dried grains plus solubles by dairy cows in early lactation. J. Dairy Sci. 65: Powers, W. J., H. H. Van Horn, B. Harris, Jr., and J. Wilcox Effects of variable sources of distillers dried grains plus solubles on milk yield and composition. J. Dairy Sci. 78: Shelford, J. A., and R. M. Tait Composition of distillers grains with solubles from rye and corn in production and digestibility trials with lactating cows and sheep. Can. J. Anim. Sci. 66: Staples, C. R., B. S. Oldick, E. Hirchert, and J. Velasquez Identifying the effective fiber value of whiskey solubles in lactating dairy cow diets. Proc. 6th Annual Florida Ruminant Nutr. Symp. p Stern, M. D., S. Calsamiglia, A. Ferret, and A. Bach Protein contributions from alternative feeds. Proc. 2nd National Alternative Feeds Symp. p Van Horn, H. H., O. Blanco, B. Harris, Jr., and D. K. Beede Interaction of protein percent with caloric density and protein source for lactating cows. J. Dairy Sci. 68: Weiss, W. P., D. O. Erickson, G. M. Erickson, and G. R. Fisher Barley distillers grains as a protein supplement for dairy cows. J. Dairy Sci. 72:

59

60 USES OF CORN COPRODUCTS IN BEEF AND DAIRY RATIONS Terry Klopfenstein and Rick Grant University of Nebraska, Lincoln USE OF CORN COPRODUCTS FOR BEEF CATTLE Distillers grains (DG) are an excellent ruminant feedstuff. They are an excellent source both of energy and protein. In the production of alcohol, the starch, which is about two-thirds the composition of corn grain, is fermented to alcohol and CO 2. The remaining nutrients are then concentrated by a factor of three. Corn protein of 10% is concentrated to 30% and fat (oil) from 4 to 12%. Fiber is concentrated from 14 to 42%. The fiber is highly digestible and the fat has about three times the energy of starch. The protein is high in undegraded intake protein (UIP). The DG can be used as both a protein source and an energy source for growing cattle and for finishing cattle. For growing cattle, the value of the UIP is most important. The DG are normally available for use in feedlot finishing diets in two forms, dried distillers and wet distillers grains. In general, there are two nutritional philosophies regarding their use in feedlot finishing diets. The DG can be fed at 6 to 15% of the diet dry matter (DM), serving primarily as a source of supplemental protein. When fed at higher levels (greater than 15% of the diet DM), the byproduct's primary role is as a source of energy replacing corn grain. Other than DM content (wet DG, 35-45%; dried DG, 90-95%), the chemical composition of the two products is similar. Dried DG is routinely fed as a supplemental protein source; however, the drying process appears to reduce the energy value of the DG. Ham et al. (1994) demonstrated a 9% improvement in feed efficiency when dried DG replaced 40% of the dry-rolled corn in finishing diets (Table 1). However, this improvement was only 50% of that observed when wet DG byproduct replaced a similar amount of dry-rolled corn. Drying cost significantly increases the commodity price for the DG. The dried DG is routinely priced relative to other supplemental protein sources like soybean meal. Therefore, when priced on an energy basis (relative to corn), the expected improvement in animal performance is not large enough to offset the increased ration cost associated with higher inclusion levels. Wet DG are commonly fed at higher levels in the diet to supply both protein and energy to the animal. There are numerous advantages to using wet DG. For the dry-milling plant, the energy cost associated with drying the product can be significantly reduced or eliminated. This should allow for an overall increased energy yield for each bushel of corn processed. The major downside of using wet DG is transportation costs associated with the movement of water. Experiments evaluating the use of wet DG in feedlot diets are available (DeHaan et al, 1983; Farlin, 1983; Firkins et al., 1985; Ham et al., 1994; Fanning et al., 1999; Larson et al., 1993; Lodge et al., 1997a; Trenkle, 1997a; Trenkle, 1997b). In the experiments with finishing cattle, the replacement of corn grain with wet DG consistently improved feed efficiency. Larson et al. (1993) replaced dry-rolled corn with 5.2, 12.6, or 40% (DM basis) wet DG (Table 2). With the

61 first two levels of byproduct (5.2 and 12.6%), these researchers observed a 7% increase in feed efficiency above the basal dry-rolled corn diet. But, when the inclusion level was increased to 40% of the diet DM, the improvement in feed efficiency was 20% above the dry-rolled corn diet. In other published experiments (Ham et al., 1994; Fanning et al., 1999; Lodge et al., 1997a), the inclusion level of the wet distillers byproduct has been 30 to 40% of the diet DM. These experiments consistently suggest a 15 to 25% improvement in feed efficiency when 30 to 40% of the corn grain is replaced with wet DG. Eleven experiments were summarized where wet DG was compared with corn as an energy source for finishing cattle (Table 3). The wet DG replaced 12.6 to 50% of the diet (corn). The data were summarized into three situations. First is the control diet based on dry-rolled corn. Second is when wet DG replaced corn at a low level in the diet (12.6 to 28%). The third situation is where wet DG replaced corn in the diet at 30 to 50% of dietary DM. At the low level (average 17.4%) of wet DG feeding, the energy value was 152% that of corn. At the high level of feeding, the value decreased to 136% the value of corn. We can then calculate the value of the wet DG as 124% the value of corn when fed between 17.4 and 40% of the diet. We believe there are very good explanations for the change in relative feeding values as wet DG increases in the diet. We believe the first increments fed (up to 17.4%) supply nutrients such as protein that may be of value to the cattle, but more importantly, reduce the acidosis that occurs in the control diet. The wet DG contains protein and fat which supply energy to the animal, but it does not contain the starch that leads to acidosis. Further, the fiber (hull) in the wet DG is highly digestible but adds fiber to the diet and reduces acidosis. So, the very high value of the wet DG (152%) at low level feeding is probably due to factors other than the strict energy value of the nutrients contained therein. The value when fed above 17.4% of the diet is probably due to the high fat content of the wet DG and the high content of bypass protein. Fat has about three times the energy value of starch for cattle and bypass protein has about 30% more energy than starch. The value from feeding trials was determined to be 124% the value of corn. By calculating the theoretical energy value based on the bypass protein and fat contents, we estimate the energy value of wet DG to be 120% the value of corn. This calculation gives confidence in the value obtained from feeding trials. Typical feedlot diets contain about 85% corn. The starch in the corn is the energy source used by the cattle. However, the starch is rapidly fermented by the rumen microorganisms to organic acids. The overproduction of the organic acids causes acidosis followed by reduced feed intake and reduced gains (Stock and Britton, 1993; Stock et al., 1995). Distillers byproducts have essentially all of the starch removed leaving protein, highly digestible fiber, and fat. The feeding of the byproducts appears to reduce acidosis and enhances feed efficiency. There are at least three factors involved in the higher feeding value for distillers byproducts (protein, energy, acidosis). Based on the limited data available regarding the level of wet distillers byproduct in the diet, the economic value of the byproduct varies as the level fed in the

62 diet changes. Also, as the level fed increases, more is fed per animal per day and more total byproduct would be fed. The precise relationship between level of byproduct in the diet and both the feeding value and economic value remains elusive. Corn gluten feed is the other important corn milling byproduct. It is produced by the wet milling process and the byproduct is quite different from DG. Gluten feed contains the fiber from the corn but does not contain the fat or the zein protein (the high bypass protein) that is in the distillers grains. The gluten feed contains steep liquor, distillers solubles, corn bran, and germ meal in varying combinations. Stock et al. (2000) have summarized the feeding values of two different gluten feeds for feedlot cattle. For the first product (Table 4), the feed efficiency (feed:gain ratio) was essentially equal between the control (corn) diets and the diets containing gluten feed. This suggests equal energy value for gluten feed and corn. Product B (Table 5) had dietary feed efficiencies 5% better than the control indicating higher energy value for the gluten feed than for the corn grain it replaced. Gluten feed, like DG, helps control acidosis. The gluten feed is actually less digestible than corn grain (Bierman et al., 1995) but has equal or higher apparent energy in feedlot diets because it controls acidosis. Gluten feed is an excellent protein and energy supplement for growing calves or beef cows. It was used as a supplement for growing calves grazing corn stalks. In the range of 5 to 6 lb DM per day, gain was optimized and the supplemental needs for protein and phosphorus were met with gluten feed (Figure 1). Jordon et al. (2001b) have shown it to be a very cost effective supplement for growing calves. USE OF CORN COPRODUCTS FOR DAIRY CATTLE Coproducts of wet and dry milling, most notably DG and corn gluten feed (CGF), have been used conservatively as forage and concentrate replacements in diets for lactating dairy cattle. Commonly, DG and CGF are fed at 20% of the dietary DM, but recent research indicates that substantially more can in fact be fed, especially for CGF. Maximizing the use of these corn coproducts in ruminant diets will become increasingly important as more ethanol plants are built in the near future. An understanding of the chemical composition of these coproducts enables us to effectively position them in dairy formulations. Both contain 40 to 45% NDF which is highly digestible (6-8%/h digestion rate) due to low lignification and can therefore replace starch (10-30%/h digestion rate) and reduce the risk of ruminal acidosis (Allen and Grant, 2000). Due to their small particle size, both coproducts have <15% physically effective NDF and so do not stimulate much rumination (Clark and Armentano, 1993; Allen and Grant, 2000). Consequently, particle size of forage is a critical issue when either coproduct replaces forage. Major compositional differences between DG and CGF include lipid and protein fractions. Distillers grains, wet or dry, contain 30 to 35% CP, of which ~55% is ruminally undegradable protein (RUP). In contrast, CGF contains 20 to 25% CP and only 25 to 30% RUP. The lipid content of DG is 10 to 15%, but <3% for CGF. These differences in physicochemical properties have positioned CGF primarily as a source of digestible NDF, whereas DG have been positioned as a source of RUP.

63 However, there is no reason why, with proper supplemention and forage combinations, that both coproducts could not serve as sources of RUP and energy. This section will focus on recent research aimed at optimizing the nutritional properties of these two coproducts and maximizing incorporation of them into diets for lactating dairy cows. For more comprehensive summaries of milk production responses to CGF or DG, refer to reviews by Chase (1991) and Schingoethe (2001). Corn Gluten Feed for Dairy Cows A summary of beef feedlot research (Stock et al., 2000) indicated that efficiency of gain was improved by 5.1% when diets contained 25 to 50% wet CGF (corn bran:steep liquor, 1:1 DM basis) were compared with dry-rolled corn. This positive response was likely due to reduced ruminal acidosis and increased DMI. Ruminal acidosis is a significant concern when feeding dairy cows as well because of the need for optimal ruminal fiber digestion in the presence of substantial amounts of starchy concentrate feeds. Corn bran is rapidly and extensively digested in the rumen. Consequently, the dilution of starch with NDF from CGF results in slower rates of fermentation, reduced acid load in the rumen per unit of fermentation time, and the ability to feed a highly digestible diet with low risk of ruminal acidosis. Nonforage sources of fiber, such as CGF, do not stimulate rumination as effectively as forages. Therefore, it is necessary for dietary forage to have adequate particle length for normal rumination when replacing forage. Additionally, forage of longer particle length forms a digesta mat that more effectively filters and entangles smaller particles allowing greater time for fermentation in the rumen (Welch, 1982). Allen and Grant (2000) evaluated the effect of ruminal mat consistency on passage and digestion kinetics of wet CGF in dairy cattle. Table 6 summarizes the diets and key responses. Two diets were formulated to contain ~40% alfalfa, 24% wet CGF, plus a corn and soybean meal-based concentrate. One diet contained alfalfa silage and the other contained a 1:1 blend of alfalfa silage and coarsely chopped alfalfa hay of similar quality. Compared with the diet without added hay, the diet with added hay had 59% more long particles, a 37% increase in ruminal mat consistency, a 27% increase in rumination, equal NDF intake, but a 35% reduction in passage rate of CGF, an increase in ruminal NDF digestion of nearly 40%, and an increase in 4% fat-corrected milk (FCM) of 5.5%. Both diets contained 24% wet CGF, and this research points out the potential to manipulate passage and digestion of CGF to maximize NDF fermentation in the rumen. Though the research has not been conducted, presumably a similar response would be observed for DG since they have similar particle size and specific gravity as CGF. Fibrous coproducts can contribute more to highly digestible diets than previously thought if their passage and digestion kinetics are optimized, in addition to ensuring adequate physically effective NDF in the total diet. One problem with the design of much previous research that evaluated CGF for dairy cows has been that diets were balanced for CP, but not metabolizable protein (MP). Wet CGF contains twice as much CP as corn, but less MP (Krishnamoorthy et al., 1982; Stock et al., 2000). Thus, control diets containing corn grain, which use soybean meal to balance for CP, may contain CP concentrations similar to CGF diets, but these control diets also contain substantially greater amounts of MP. If MP is not adequate for diets containing CGF, erroneous conclusions may be made concerning their nutritional value. Several studies have indicated that 20% dietary wet

64 CGF is optimal for milk production (Droppo et al., 1982; Gunderson et al., 1988; Schroeder and Park, 1997). However, MP may have been limiting milk production rather than energy or effective NDF beyond 20% inclusion. Recently, a series of studies (Boddugari et al., 2001) were conducted to develop a new wet CGF product based on ingredients from the wet milling process to enhance the MP content and to determine the maximal amount of this product that could be incorporated into the diet. The hypothesis was that a properly formulated wet CGF product could be fed in amounts much greater than currently practiced by the dairy industry. The wet corn milling feed product (CMP) developed was composed of corn bran, fermented corn extractives (steep liquor), corn germ meal, and additional sources of RUP to increase the MP content of the product. The CMP contained 23.1% CP, 43.0% RUP (% of CP), 13.7% ADF, 40.3% NDF, and 2.6% lipid (DM basis). For comparison, the nutrient profile of the wet CGF from the wet milling plant that provided the CMP is 22.5% CP, 30.0% RUP, 14.0% ADF, 43.0% NDF, and 2.5% lipid. Clearly, the major difference was an improvement in the RUP content of the CGF. In the first trial, four diets were evaluated that contained 54.3% forage with the CMP replacing either 0, 50, 75, or 100% of the concentrate. All of the diets containing CMP resulted in 7.8% lower DMI, equivalent milk production, and 13.6% greater efficiency of FCM production than the control diet. In a subsequent trial, the 100% concentrate replacement diet served as the control diet and 15, 30, or 45% of the forage was replaced with CMP. Production of 4% FCM and efficiency of FCM were unaffected by diet, but rumination decreased for the 30 and 45% replacement diets, although ruminal ph was unaffected. These two trials demonstrated, at least in short-term studies (4-wk periods), that up to 70% of the dietary DM could be comprised of CMP, which is far greater than previously published studies. A final study (Boddugari et al., 2001) was designed to evaluate an optimal amount of CMP in the diet for early lactation cows. Cows were assigned, from day 1 to 63 of lactation, to either a control diet (no CMP) or a diet containing 40% CMP. The 40% level was chosen because the maximal effect on efficiency of FCM production was achieved at 50% concentrate replacement and 30% forage replacement in the previous trials. Table 7 summarizes the production responses to these diets. The diet containing the CMP resulted in a 21% greater efficiency of FCM production than the control diet. This series of studies showed that up to 70% of the diet can be replaced by a properly formulated wet CGF product, and that 40% of the dietary DM may be an optimal amount to feed. A key concept is that by correcting a deficiency in the coproduct feed (MP in this case), we were able to feed more and substantially increase the amount of energy the cow captured from digestible NDF, rather than starch, which should result in healthier, more productive cows long-term. Distillers Grains for Dairy Cows Most research has focused on DG as an alternative protein source to soybean meal (Owen and Larson, 1991 as an example). However, DG also is an excellent source of energy due to its high content of digestible NDF and lipid. In a recent review, Schingoethe (2001) suggested a maximum of 20% DG in the dietary DM fearing potential palatability problems and excessive protein consumption above this amount. However, a recent trial (Schingoethe et al., 1999) found

65 that diets containing 31.2% wet corn DG versus a control diet (corn-soybean meal-based) resulted in a 13.6% increase in efficiency of energy-corrected milk production. The forage component of these diets contained ~63% corn silage and 37% alfalfa hay and resulted in a total dietary CP content of 21% and 22% elevation of serum urea levels. So, long-term considerations when feeding high levels of corn DG need to be: 1) proper ratio of forage sources to reduce dietary CP, and 2) supplemental sources of lysine if corn silage comprises the majority of the forage. It appears that total CP, and possibly lipid, in the diet will set upper limits on the amount of DG that can be incorporated into the ration, but 20 to 30% is feasible if the ration is properly formulated. Logical possibilities exist to combine DG and CGF to capitalize on the unique attributes of both coproducts (digestible NDF from CGF and RUP plus lipid from DG) to create products that would allow higher levels of inclusion in the diet and increase efficiency of milk production. In addition, there is evidence that the lipid in corn DG is effective at increasing the unsaturated to saturated fatty acid ratio in milk fat (Schingoethe et al., 1999). Two major questions concerning use of DG by dairy cows are: 1) is there a difference between wet and dry DG, and 2) does source of grain for the fermentation impact the nutritive value of the DG. One study (Al-Suwaiegh et al., 1999) has compared wet versus dry DG from the fermentation of either 100% corn or 100% sorghum. All the diets contained 50% of a 1:1 mixture of alfalfa and corn silages and 15% DG. Chemical composition of the corn and sorghum DG were similar. Efficiency of FCM production was similar for cows fed either corn or sorghum DG in the wet or dry form (Table 8). Since efficiency was the same, whether wet or dry, the form of the DG is primarily a function of what works best for the farm given the feed storage and handling capabilities. The production of 4% FCM tended to be reduced when cows were fed DG from sorghum versus corn. The impact of grain source on the quality of DG and its effect on long-term milk production is unknown. Because we know that wet and dry DG are similar, a study needs to be conducted that compares either wet or dry DG fed continuously during early lactation. Feeding DG and CGF to Dairy Cows: Bottom Line Unquestionably, DG and CGF are excellent sources of digestible NDF, RUP, and lipid for dairy cattle diets. Particularly for CGF, much more (at least 2x) can be incorporated into diets than has been previously recommended. We need to consider the nutrient profile of these coproducts, and supplement to correct any nutrient deficiencies, either to the diet or by creatively combining various milling coproducts. In addition, we need to manipulate the physical as well as the chemical properties of the forage component of the diet to maximize the use of these coproducts. There is tremendous potential to combine corn milling coproducts that will allow maximal replacement of forage and concentrate. This approach will likely become more important as more ethanol plants are built over the next several years. The traditional paradigm in feeding dairy cattle has been to maximize the amount of forage in the diet which necessitates an exquisite focus on forage quality. However, when high quality forage is expensive or in limited supply, or in areas where coproducts are abundant, the paradigm needs to shift to maximizing use of the byproduct and ensuring that the forage meets the minimal requirements for physically effective NDF. Both DG and CGF products should be effective at providing a consistent quality, highly digestible diet for lactating dairy cows.

66 Literature Cited Allen, D. M., and R. J. Grant Interactions between forage and wet corn gluten feed as sources of fiber in diets for lactating dairy cows. J. Dairy Sci. 83: Al-Suwaiegh, S., R. J. Grant, C. T. Milton, and K. Fanning Corn versus sorghum distillers grains for lactating dairy cows Nebraska Dairy Report. MP74-A, Univ. of Nebraska Coop. Ext. Serv., Lincoln, NE. Bierman, S. J Nutritional effects on waste management. M.S. thesis. Univ. of Nebraska, Lincoln. Boddugari, K., R. J. Grant, R. Stock, and M. Lewis Maximal replacement of forage and concentrate with a new wet corn milling product for lactating dairy cows. J. Dairy Sci. 84: Chase, L. E Feeding distillers grains and hominy feed. Proc. Alternative Feeds for Dairy and Beef Cattle. Natl. Invitational Sympos., St. Louis, MO. Sept Clark, P. W., and L. E. Armentano Effectiveness of neutral detergent fiber in whole cottonseed and dried distillers grains compared with alfalfa haylage. J. Dairy Sci. 76: DeHann, K., T. Klopfenstein, R. Stock, S. Abrams and R. Britton Wet distillers byproducts for growing ruminants. Nebraska Beef Rep. MP-43:33. Droppo, T. E., G. K. Macleod, D. G. Grieve, and J. D. Summers Feed value of moist corn gluten feed for dairy cows. J. Anim. Sci. 55:121. Fanning, K, T. Milton, T. Klopfenstein and M. Klemesrud Corn and sorghum distillers grains for finishing cattle. Nebraska Beef Rep. MP-71-A:32. Farlin, S.D Wet distillers grains for finishing cattle. Amin. Nutr.'Health 36:35. Firkins, J. L., L. L. Berger and G. C. Fahey, Jr Evaluation of wet and dry distillers grains and wet and dry corn gluten feeds for ruminants. J. Anim. Sci. 60:847. Gunderson, S. L., A. A. Aguilar, and D. E. Johnson Nutritional value of wet corn gluten feed for sheep and lactating dairy cows. J. Dairy Sci. 71: Ham, G. A., R. A. Stock, T. J. Klopfenstein, and R. P. Huffman Determining the net energy value of wet and dry corn gluten feed in beef growing and finishing diets. J. Anim. Sci. 73: Ham, G. A., R. A. Stock, T. J. Klopfenstein, E. M. Larson, D. H. Shain and R. P. Huffman

67 Wet corn distillers byproducts compared with dried corn distillers grains with solubles as a source of protein and energy for ruminant. J. Anim. Sci. 72: Herold, D., M. Klemesrud, T. Klopfenstein, T. Milton, and R. Stock Solvent-extracted germ meal, corn bran, and steep liquor blends for finishing steers. Nebraska Beef Cattle Rep. MP 69-A: Jordan, D. J., T. Klopfenstein, and T. Milton Wet corn gluten feed supplementation of calves grazing corn residue. Nebraska Beef Cattle Report. MP 76A:41 Jordon, D. J., T. Klopfenstein, T. Milton, and R. Cooper. 2001b. Compensatory growth and slaughter breakevens of yearling cattle. Nebraska Beef Cattle Report. MP 76-A:29. Krehbiel, C. R., R. A. Stock, D. W. Herold, D. H. Shain, G. A. Ham, and J. E. Carulla Feeding wet corn gluten feed to reduce subacute acidosis in cattle. J. Anim. Sci. 73: Krishnamoorthy, V., T. V. Muscato, C. J. Sniffen, and P. J. Van Soest Nitrogen fractions in selected feedstuffs. J. Dairy Sci. 65: Larson, E. M., R. A. Stock, T. J. Klopfenstein, M. H. Sindt and R. P. Huffman Feeding value for wet distillers byproducts from finishing ruminants. J. Anim. Sci. 71:2228. Lodge, S. L., R. A. Stock, T. J. Klopfenstein, D. H. Shain and D. W. Herold. 1997a. Evaluation of corn and sorghum distillers byproducts. J. Anim. Sci. 75:37. Lodge, S. L., R. A. Stock, T. J. Klopfenstein, D. H. Shain, and D. W. Herold. 1997b. Evaluation of wet distillers composite for finishing ruminants. J. Anim. Sci. 75: McCoy, R. A., R. A. Stock. T. J. Klopfenstein, D. H. Shain, and M. J. Klemesrud Effect of energy source and escape protein on receiving and finishing performance and health of calves. J. Anim. Sci. 76: NRC Nutrient Requirements of Beef Cattle (7" Ed.). National Academy Press, Washington, DC. Owen, F. G., and L. L. Larson Corn distillers dried grains versus soybean meal in lactation diets. J. Dairy Sci. 74: Richards, C., R. Stock, and T. Klopfenstein Evaluation of levels of wet corn gluten feed and addition of tallow. Nebraska Beef Cattle Rep. MP 66-A: Richards, C. J., R. A. Stock, T. J. Klopfenstein, and D. H. Shain Effect of wet corn gluten feed, supplemental protein, and tallow on steer finishing performance. J. Anim. Sci. 76:

68 Schingoethe, D. J Feeding wet distillers grains to dairy cattle. Proc. Distillers Grains Technol. Council. 5 th Ann. Symp., Louisville, KY. May Schingoethe, D. J., M. J. Brouk, and C. P. Birkelo Milk production and composition from cows fed wet corn distillers grains. J. Dairy Sci. 82: Schroeder, J. W., and C. S. Park Optimizing level of wet corn gluten feed, storage form, and altering intake protein degradability in diets for lactating Holstein dairy cows. J. Dairy Sci. 80:248. Scott, T., T. Klopfenstein, D. Shain, and M. Klemesrud. 1997a. Wet corn gluten feed as a source of rumen degradable protein for finishing steers. Nebraska Beef Cattle Rep. MP 67-A: Scott, T., T. Klopfenstein, R. Stock, and M. Klemesrud. 1997b. Evaluation of corn bran and corn steep liquor for finishing steers. Nebraska Beef Cattle Rep. MP 67-A: Stock, R.A. and R.A. Britton Acidosis in Feedlot Cattle. In: Scientific Update on Rumensin/Tylan for the Profession Feedlot Consultant. Elanco Animal Health, Indianapolis, IN. p A-1. Stock, R. A., T. J. Klopfenstein and D. Shain Feed intake variation. In: Symposium; Intake by Feedlot Cattle. Oklahoma Agr. Exp. Sta. P-942:56. Stock, R. A., J. M. Lewis, T. J. Klopfenstein, and C. T. Milton Review of new information on the use of wet and dry milling byproducts in feedlot diets. Proceedings of the American Society of Animal Science, 1999 (on line serial). Trenkle, A. 1997a. Evaluation of wet distillers grains in finishing diets for yearling steers. Beef Research Report- Iowa State Univ. ASRI 450. Trenkle, A. 1997b. Substituting wet distillers grains or condensed solubles for corn grain in finishing diets for yearling heifers. Beef Research Report - Iowa State Univ. ASRI 451. Welch, J. G Rumination, particle size, and passage from the rumen. J. Anim. Sci. 54: Table 1. Energy Value of Wet vs Dry Distillers Grains Control Wet Low a Medium a High a Daily feed, lb 24.2 bc 23.5 b 25.3 c 25.0 c 25.9 c Daily gain, lb 3.23 b 3.71 c 3.66 c 3.71 c 3.76 c Feed/gain 7.69 b 6.33 c 6.94 d 6.76 d 6.90 d Improvement: Diet (ave.) Distillers vs corn a Level of ADIN, 9.7, 17.5 and 28.8%. b,c,d Means in same row with different superscripts differ (P < 0.05).

69 Table 2. Effect of Wet Distillers Grains Level on Finishing Performance of Yearlings and Calves DG level, % of diet DM a Item Daily feed, lb Yearlings b Calves b Daily gain, lb Yearlings c Calves b Feed/gain d Yearlings e Calves b a Wet grains:thin stillage (fed ratio), yearlings = 1.67:1; calves = 1.81:1, DM basis. b Byproduct level, linear (P < 0.01). c Byproduct level, linear (P < 0.10); quadratic (P < 0.10). d Feed/gain analyzed as gain/feed. Feed/gain is reciprocal of gain/feed. e Byproduct level, linear (P < 0.10).

70 Table 3. Influence of Level in Diet on Value of Wet Distillers Grains Plus Solubles in Feedlot Diets Wet DG level in diet dry matter Experiment % 30-50% Trenkle, 1997a.154 a.183 (20) b.176 (40) b 194% c 137% c Trenkle, 1997a (40) 136% Trenkle, 1997b (16).168 (40) 126% 102% Trenkle, 1997b (28) 114% Firkins et al., (25).171 (50) 101% 121% Larson et al., (12.6).173 (40) 177% 150% Larson et al., (12.6).177 (40) 164% 135% Ham et al., (40) 147% Fanning et al., (30) 147% Means 152% (17.4) 136% (40) Value 17.4 to % a Feed efficiency. b Level in diet dry matter. c Value relative to corn.

71 Table 4. Energy Value of WCGF-A a for Beef Finishing Cattle Amount in diet, Number of Relative Reference % of DM replications feed:gain b Bierman (1995) Ham et al. (1995); Trial Ham et al. (1995); Trial Krehbiel et al. (1995) c.96 Lodge et al. (1997b) c 1.00 McCoy et al. (1998); Trial McCoy et al. (1998); Trial Average, all levels Average, 20 to 60% of diet DM a WCGF-A = wet corn gluten feed, 40% DM content. b Calculated as feed/gain of control diet divided by feed/gain of treatment diet. c Individually fed cattle trial. Treatment assigned two pen replications for calculation purposes. Table 5. Energy Value of WCGF-B a for Beef Finishing Cattle Amount in diet, Number of Relative Reference % of DM replications feed;gain b Richards et al. (1996) Scott et al. (1997a) Scott et al. (1997b) c c.92 Herold et al. (1998) Richards et al. (1998) Average, all levels Average, 20 to 60% of diet DM a WCGF-B = wet corn gluten feed, 60% DM content. b Calculated as feed/gain of control diet divided by feed/gain of treatment diet. c Individually fed cattle trial. Treatment assigned two pen replications for calculation purposes.

72 Table 6. Ruminal passage and digestion of wet corn gluten feed (CGF). Item CGF CGF + Hay Ingredients, % of DM Alfalfa silage Alfalfa hay 18.8 Wet CGF Concentrate mix % Particles 9.5 mm screen NDF intake, % of BW Ruminal mat consistency, ascension rate, cm/sec 0.26 a 0.19 b Passage rate of CGF, %/h 6.40 a 4.20 b Apparent extent of ruminal NDF digestion, % 32.4 b 44.8 a Rumination, min/kg NDF intake 46.5 b 59.2 a 4% Fat-corrected milk, kg/d ab Means within row with unlike superscript differ (P < 0.10). Table 7. Performance of dairy cows fed 40% wet corn milling feed product (CMP) from day 1 to 63 of lactation. Item 0% CMP 40% CMP DMI, % of BW 4.27 a 4.06 b NDF intake, % of BW 1.16 b 1.40 a 4% FCM, kg/d 38.5 b 44.6 a FCM/DMI, kg/kg 1.47 b 1.79 a Body condition score ab Means within row with unlike superscripts differ (P < 0.05). Table 8. Wet versus dry distillers grains (DG) from corn or sorghum fed at 15% of ration DM. Corn DG Sorghum DG Item Dry Wet Dry Wet DMI, % of BW % FCM, kg/d FCM/DMI, kg/kg Milk fat, % Milk protein, %

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74 The Advantages of Using Corn Distillers Dried Grains with Solubles in Dairy Beef Diets An Economical Addition to Dairy Beef Diets: Dry distillers grains with solubles is an excellent feed for growing Holstein steers Recent research results from Iowa State University have shown that 10, 20 or 40% of the ration dry matter as dry distillers grains with solubles could be fed to growing Holstein steers from 425 to 700 lbs without affecting feed intake or gain. Feeding wet distillers grains with solubles tended to decrease feed intake of the growing steers, but improved feed conversion. Feed cost of gain was reduced 6% when corn was priced at $2.25/bu and dry distillers grains at $85/ton. At the same prices, feeding wet distillers grains reduced cost of gain 13%. Wet or dry distillers grains can be fed to growing and finishing Holstein steers During the 299-day feeding trial, feeding dry distillers grains at 10, 20 or 40% of ration dry matter did not affect feedlot performance or cost of gain. Steers fed 10% wet distillers grains were 4% more efficient and had 5% lower feed cost of gain. Feeding 40% of ration dry matter as wet distillers grains reduced feed intake and rate of gain with similar feed conversion and cost of gain. Feeding distillers grains to growing and finishing Holstein steers can increase profits With corn prices at $2.25/bu, there is profit from feeding 10, 20 or 40% distillers grains to growing Holstein steers if the price of distillers grains is less than $100/ton ($33/ton for wet distillers grains with 30% dry matter). When price of distillers grains is low compared with corn, there are greater profits from feeding higher levels. During the growing and finishing period with corn at $2.25/bu, the price of dry distillers grains had to be less than $85/ton to profitably include it in the ration. Feeding 10 or 20% wet distillers grains to growing and finishing Holstein steers continued to be profitable with the price of the wet grains at $33/ton. Feeding wet or dry distillers grains does not affect carcass value Feeding 10, 20 or 40% dry distillers grains or 10 and 20% wet distillers grains did not affect carcass weight, marbling, or yield grades. Steers fed 40% wet distillers grains had lighter carcasses but similar marbling and yield grades. Carcass value based on grade and yield or a marketing grid with premiums or discounts for quality and yield grades was not affected by feeding wet or dry distillers grains. Keys to feeding distillers grains to Holstein steers Make changes in the ration to account for the nutrients supplied by distillers grains, namely protein and phosphorus. Maintain adequate quantities of effective fiber in the rations containing distillers grains. Keep the supply of wet distillers grains fresh. Feed the steers to similar final weight as those not fed distillers grains. For additional information on feeding distillers grains to cattle contact: Allen Trenkle Department of Animal Science Iowa State University Ames, Iowa /19/2004

75 Distiller Grain Trial Rincker and Berger (2003) OPTIMIZING THE USE OF DISTILLER GRAIN FOR DAIRY-BEEF PRODUCTION C.B. Rincker and L.L. Berger University of Illinois SUMMARY Optimizing the use of distiller grain (DG) is becoming increasingly important as ethanol production increases. Dairy-beef production is a system that has the potential to use large amounts of DG. Threehundred and twenty Holstein steers ( lbs initial wt.) were fed finishing diets at the University of Illinois Beef Research Unit. Forty pens were each randomly assigned to ten treatments with eight calves per pen. Ten dietary treatments of various DG levels were randomly assigned to 4 different pens. The calves were fed ad libitum and the cattle were weighed in 28-day intervals. After 112 days, both treatments 7 and 8 along with 9 and 10 were switched to represent the change from 20% to 37.5% and from 37.5% to 20% for both wet distiller grain (WDG) and dry distiller grain (DDG) (DM basis). Implants were administered twice during the course of the trial. Fecal samples were collected on a per pen basis, sub sampled, and then analyzed for nitrogen (N), phosphorus (P), and sulfur (S). Cattle were then weighed at 270 d and sent to Packerland (Green Bay, WI) to be harvested. Effects of dietary treatment were analyzed using the GLM procedure of SAS. Orthogonal contrasts were used for the control versus DG diets, DDG versus WDG, and diet change from 20 to 37.5% DG versus 37.5 to 20% DG (represented in treatments 7 through 10). Linear and quadratic contrasts were also used for the level of DDG and WDG. Performance values for average daily gain (ADG), dry matter intake (DMI), and feed efficiency expressed in feed:gain (F:G) were evaluated for the growing period (112 d) and for the entire trial (270 d). Steers fed all treatments performed well and the use of DG showed the potential to improve profitability. Steers had a significant linear decrease in ADG with an increasing level of WDG diets (P=.0202) and steers which shifted from high DG to (37.5%) low DG (20%) had significantly lower ADG than steers switched from low DG (20%) to high DG (37.5%) (P=.0035). There was a significant quadratic effect on DMI with increasing WDG (P<.0001). Steers fed 25% WDG ate more DM than those fed 0% or 50% WDG. There was a linear increase in F:G as the level of DDG increased (P=.0266). Steers had a quadratic response in F:G with WDG levels (P=.0296). Steers fed 50% WDG were the most efficient (5.68 F:G). WDG diets were significantly more efficient when contrasted against DDG diets (P=.0009). There was a linear increase in both P and S levels in the feces with increasing DDG (P<.0001, <.0001) and a quadratic effect for WDG treatments (P=.0403, 0356). When harvested, steers fed DG had a higher dressing percent (DP) than control (P=.03). The most profitable diets were determined by the relative price of corn and DG. When DDG was priced at $110/ton and WDG $100 with $2.50/bushel corn, low levels ( %) tended to be most profitable. When DDG were priced at $90/ton and WDG at $80/ton with $2.50/bushel corn, the % diets tended to be most profitable. 1

76 Distiller Grain Trial Rincker and Berger (2003) INTRODUCTION Corn distiller grain (DG) is a by-product of ethanol production. During alcohol production, starch is removed from the grain and converted to alcohol and carbon dioxide. As a result of the starch removal, the remaining nutrients in the grain is concentrated approximately threefold (Spiehs et al. 2002). The demand for ethanol is increasing. This trend will result in an abundance of byproducts, like DG that are potential alternatives to corn (Lodge et al. 1997). Many are projecting a threefold increase of DG production within the next decade. Maximizing the value of DG will benefit both the ethanol industry and cattle producers alike. Dairy-beef producers have a plethora of protein and energy sources available to incorporate in their diets, and DG should be a competitive nutrient source. There has been extensive research completed at the University of Illinois on the nutritional value of wet (WDG) and dry (DDG) distillers grains (Firkins et al and Firkins et al. 1985) and on the nutritional requirements of dairy-beef steers (Hussein and Berger, 1995). Feeding DG in dairy-beef production can be valuable because of the higher protein requirement of the light calves. Research trials conducted at Illinois (Firkins et al. 1984), Nebraska (DeHaan et al. 1982), and Iowa State (Trenkel et al. 1981) demonstrated that DG protein has more than twice the bypass value (undegraded intake protein) compared to soybean meal (SBM). The treatments, as shown in Table 1, were based on previous research with beef steers. Treatments 1 through 4 were selected based on a 1985 study by Firkins and co-workers where finishing steers fed 25 or 50% WDG gained faster and more efficiently than control steers receiving an 87% concentrate diet. When the energy value was expressed relative to corn, the 25 and 50% WDG had values of 103 and 122%, respectively. In addition, a 1986 Nebraska summary (Aines et al. 1986) of five different trials demonstrated that DG average 109% the energy of corn for finishing beef steers. By feeding a combination of DG and urea (Treatment 2), the diet should be equal to SBM by meeting the protein requirements of the growing dairy-beef steer. This combination of urea and DG will be much cheaper per unit of crude protein (CP) compared to SBM. Depending on the protein concentration of the basal ingredients, the 25% DDG diet (Treatment 3) will meet and slightly exceed the protein requirements of growing steers. The high-energy value of the distillers, however, may cause the economics to favor feeding extra protein. This level of distillers may also reduce the risk of subclinical acidosis without reducing intake, which is especially important for dairy-beef steers that are often on high-energy diets for around 300 days. The 50% DDG diet (Treatment 4) was selected since it serves as both a protein and energy source for dairy-beef steers. In a study conducted by Farlin (1981), diets as high as 64% WDG on a dry-matter (DM) basis were fed to finishing beef steers. Even though the dry matter intakes (DMI) were reduced by 11%, gains were similar and feed efficiency, expressed in feed:gain ratio (F:G) was improved 10% compared to control diet. University of Illinois research with early-weaned beef steers entering the feedlot at lbs suggest that energy intake early in the feeding program can have a great effect on the marbling level at slaughter. Increasing the energy density of the diet by feeding high levels of DDG may stimulate marbling deposition earlier in the feeding period resulting in a higher quality grade (QG) (Wertz et al. 2001). 2

77 Distiller Grain Trial Rincker and Berger (2003) Treatments 3 through 6 compared the relative value of WDG and DDG at 25 or 50% of the diet for dairy-beef steers which are important for two reasons. First, it is cheaper and more energy efficient to produce WDG than DDG. Alcohol producers can then sell WDG for slightly less than DDG on an equal DM basis and still generate the same net revenue from the byproduct stream. At the same time, WDG diets may reduce DMI in cattle if the total moisture level is too high. Farlin (1981) demonstrated that including 64% WDG (DM basis) reduced DMI 11%. With young calves the DM level in the diet may have greater effects on intake than with the yearling steers in the Farlin trial. By including the WDG and DDG at two levels, we can answer the question whether DDG is more valuable then WDG at higher inclusion rates. Previous research shows that both WDG and DDG have similar nutritional value when fed at low levels in the diet (Firkins et al. 1984). Additionally, these comparisons are important in that transporting the water in WDG is expensive. For some plants having both DDG and WDG available is the best alternative. WDG could be used by local beef and dairy producers, while those further from the source may find the DDG to be more economical. MATERIALS AND METHODS Three-hundred and fifty Holstein steer calves were purchased and sent to the Beef Research Unit at the University of Illinois in August The steers were immediately put on a pelleted grain mix and long-hay diet, ear-tagged, dewormed, and vaccinated according to their available records. The steers were gradually adjusted to an 85% concentrate-15% corn silage diet by replacing the corn silage with whole corn. The diets were balanced to meet or exceed the 1996 NRC Nutrient Requirements of Beef Cattle. The calves were vaccinated against infectious bovine rhinotracheitis (IBR), parainfluenza, clostridia, malignant edema, Haemophilus somnus, and Pasterurella. The steers were weighed on September 4, 2002 preliminarily and checked for illnesses. Those suffering from shipping fever or pinkeye were treated accordingly. The steers were weighed on September 18 and 19th on two consecutive days. The two initial weights were averaged to use as a starting weight ( lbs). Electronic Identification (E-IDs) tags were inserted in all steers. Thirty calves were culled based on health, performance, and weight to create the most uniform set to start the trial. Forty pens were randomly assigned to ten treatments with eight calves per pen. The building has an open front, south exposure, with concrete fenceline feed bunks and the pens (12 X 40 feet) were bedded with wood chips. Electric-heated waters were available in each pen and the area was cleaned on a regular basis. The management and health procedures were approved by the University of Illinois Department of Animal Resources. Ten dietary treatments that were randomly assigned to 40 different pens. The treatments are based on University of Illinois research and are as described in Table 1. Three different supplements (Table 2) were formulated to proved mineral vitamins and feed additives. The WDG and DDG grains were provided by Archer Daniels Midland (ADM) from their Peoria, Illinois plant. A sample of each dietary treatment along with both the WDG and DDG were sent to a commercial laboratory for analysis. The cattle were weighed at 28-day intervals. At 56 days, the cattle had their horns blunted with a Barnes dehorner and were implanted with Component E-S Steer Implants from VetLife with Tylan 3

78 Distiller Grain Trial Rincker and Berger (2003) (progesterone USP 200mg and estradiol benzoate 20mg with 29mg tylosin tartate for a local antibacterial). Cattle health was monitored on a daily basis and animals were treated accordingly. Three steers were removed from trial due to injury or chronic pneumonia. Also, orts were weighed back on a regular basis and subtracted from the amount fed. After 112 days, both treatments 7 and 8 along with 9 and 10 were switched according to protocol at approximately 750 lbs. This diet change represents the change from 20% to 37.5% and from 37.5% to 20% for both WDG and DDG. In March, the steers received Ralgro-Magnum implants (Schering- Plough Animal Health located in Union, NJ; dosage is72mg). In April, pens were allowed to accumulate manure for 19 to 24 d. Fecal samples were collected on a per pen basis and sub sampled. Chemical analysis was completed at a commercial laboratory for nitrogen (N), phosphorus (P), and sulfur (S). Cattle were weighed at 270 d and subsequently sent to Packerland (Green Bay, WI) to be harvested. The carcass data collected included hot carcass weight (HCW), ribeye area (REA) between the 12 th and 13 th rib via chromatography paper, backfat (BF) measured opposite of the loin, marbling scores (MS), and liver abscess scores (LA) were noted. Statistical Analysis. Effects of dietary treatment were analyzed using the general linear model (GLM) procedure of SAS (1996, SAS Inst., Inc., Cary, NC) for a randomized complete block design. Pen was used as the experimental unit for performance parameters. Individual animal was used as the experimental unit for carcass data. Orthogonal contrasts were used for the control versus DG diets, DDG versus WDG, and diet change from 20 to 37.5% DG versus 37.5 to 20% DG (Treatments 7 through 10). Linear and quadratic contrasts were also used for the level of DDG and WDG. RESULTS Performance values for ADG, DMI, and F:G for steers during the growing period (112 d) are given in Table 3. There was a significant linear decrease (P=.0021) in ADG among the diets with increasing WDG in the diet (Treatments 5, 6, and 9). There were several significant differences found in DMI. A linear increase in DMI occurred with increasing DDG (P=.0106). Likewise, a linear decrease was observed with increasing WDG (P=.0254). Finally, the contrast of WDG vs. DDG diets was found to be significant (P=.0002); steers consuming DDG having higher DMI. Additionally, there was a linear increase in F:G among increasing DDG level in the diets (Treatments 1, 2, 3, 4, and 7) (P=.0096). F:G was significantly more efficient for WDG diets when contrasted to DDG diets (P=.0369). Feedlot performance figures for the entire trial (270 d) based on carcass weight are given in Table 4. There was a significant linear decrease in ADG with increasing WDG levels (P=.0202). Steers that were switched from high DG (37.5%) to low DG (20%) (Treatments 7 and 9) versus treatments that change from low DG (20%) to high DG (37.5%) (Treatments 8 and 10) had significantly lower ADG (P=.0035). There was a significant quadratic effect on DMI with increasing WDG (P<.0001) caused by an increase between control and 25% WDG and decrease at 50% WDG (Figure 1). F:G increased linearly as DDG increased in the diets (P=.0266). There was a significant quadratic effect of WDG levels on F:G (P=.0296), shown in Figure 2, with no change in F:G from control to 25% WDG 4

79 Distiller Grain Trial Rincker and Berger (2003) (Treatment 5) and increase in efficiency (decrease in F:G) with 50% WDG (Treatment 6). WDG diets were significantly more efficient when contrasted against DDG diets (P=.0009). Fecal samples were analyzed so that N, P, and S collected on a lbs/hd per d basis could be calculated (Table 5). There were no significant differences among the diets for N composition. However, there was a linear increase in P level with increasing DDG (P<.0001). In addition, there was a quadratic affect with P level among increasing WDG in diets (P=.0403) with a decrease from 25% WDG to 37.5% WDG and then increase in P level with 50% WDG diet (Figure 3). Manure P levels, were significantly lower for steers fed WDG than DDG diets (P=.0008). Manure S levels were increased by feeding DG (Treatments 1 vs. 2-10) (P=.0026). Additionally, there was a linear increase in S level due to increasing DDG level (P<.0001). In general, carcass composition was not affected by diet (Table 6). There were significant increases in dressing percent (DP) with increasing levels of DG (P=.03). A quadratic effect on DP with DDG level (P=.0079) was found with an increase from control to 12.5% and decrease in DP at the 50% DDG level. There was a similar quadratic WDG response (P=.0031), with the highest DP at 37.5% WDG and decrease at 50% WDG. The quadratic contrasts for DP are shown in Figure 4. Also, with HCW, there was a significant quadratic affect with increasing WDG level (P=.0095) with a decrease at 50% WDG. There were no significant differences among MS, LEA, or YG (P>.05). Here again, there was a quadratic affect on BF due to increasing levels of WDG (P=.0360), with a linear increase from % WDG and decrease to 50% WDG (Figure 5). As part of the economic evaluation, profits per head were calculated at four different price intervals: $110/ton DDG and $100/ton WDG; $90/ton DDG and $80/ton WDG at either $2.50 or $2.00 per bushel corn. These values are reported in Table 7 and 8, respectfully. As shown in Figure 6 ($110/ton DDG and $100/ton WDG with $2.50/bushel corn), there were quadratic effects with both DDG and WDG level in profits per head with a linear increase from % DG and then decrease with 50% DDG and WDG, respectfully (P=.0216,.0206). When the profits were calculated at $90/ton DDG and $80/ton WDG there were more significant differences (Table 7). First, there was a significant increase in net profit per head with the DG diets vs. control (P=.0084). Second, there was a significant quadratic affect on profit with increasing DDG level (P=.0336) and a decrease at 50% DDG as shown in Figure 7. Additionally for the $90/ton DDG and $80/ton WDG cost analysis, diets consisting of WDG were significantly more profitable than DDG diets (P=.0336). There were no statistically significant differences in profitability with diets switching from % DG or % at 750 lbs (Treatments 7 through 10). Profits calculated with similar DDG and WDG prices but with $2.00/bushel corn had similar results (Table 8). When figured with $110/ton DDG and $100/ton WDG, there was a significant linear decrease in profit with increasing DDG level in the diet (P=.0093). As shown in Figure 8 ($110/ton DDG and $100/ton WDG with $2.00/bushel corn), there were quadratic effects with both DDG and WDG level in profits per head with a linear increase from % DG and then decrease with 50% DDG and WDG, respectfully (P=.0262,.0446). When the profits were calculated at $90/ton DDG and $80/ton WDG, there were similar quadratic effects as shown in Figure 9 (P=.0134,.0134). 5

80 Distiller Grain Trial Rincker and Berger (2003) DISCUSSION There was a quadratic effect of WDG (P=.0017) on DMI which dropped at the 50% WDG level (Treatment 6). Significant differences in DMI among the DDG and WDG diets are as shown in Table 4. The DDG diets possess higher means indicating that perhaps the WDG were less palatable due to the high moisture level in diet. Next, there is a linear increase in ADG with increasing WDG (Treatments 1, 5, and 6) as shown in Table 4 (P=.0202). Additionally, cattle fed lower levels of protein during the growing phase and then switched at 750 lbs. to higher levels ( % vs %) had slightly higher ADG (P=.0035). This may result from reduce sub-clinical acidosis. There was also a linear increase in F:G with increasing level of DDG in diets (P=.0266). This is in contrast to previous trials where DDG had more energy than corn. There was quadratic affect on F:G in WDG diets indicating that there was an increase from control to 25% WDG and then decrease in F:G when evaluated at 50% (Figure 2). Feed efficiency was poorer for steers fed the DDG compared to the WDG. This has been reported in previous studies and probably results from the drying process slowing fiber digestion. During the finishing period, fecal samples were evaluated for their nutrient profile (Table 5). There were no significant differences among N level (P >.05). When comparing the control diet to the DG diets (Treatments 2-10), there was a significantly higher level of S. Among increasing DDG diets, there was a linear increase in both P and S excretion (P<.0001) on a lbs/ d per head basis. In contrast, the WDG diets had a quadratic affect (Figure 4) in that the 50% WDG diet had decreased P and S concentrations in the feces compared to feces from steers on the 25% WDG diet. There is no clear explanation for this difference. Also, with P only, there were higher fecal levels with DDG diets than WDG (P=.0008). Cattle feeders need to adjust their manure application rates to reflect the high P concentration in the feces from steers fed high levels of DG. There were few statistically significant differences among the carcass composition characteristics demonstrated in Table 6. These data are important because cattle feeders selling on a grid can be assured that DG additions will not affect carcass values. In studying the profitability on a dollars/head basis, values were calculated with both $2.00 and $2.50/bushel corn for DG purchase prices of $110 DDG and $100 WDG; $90 DDG and $80 WDG. Profits were calculated with corn priced at $2.50 per bushel as that represented our average corn price delivered to the bunk during this trial. With the more expensive DG price, the least profitable diet on a net per head basis was Treatment 4 (50% DDG) with $8.13 as shown on Table 7. There was a quadratic affect with both DDG and WDG (P=.0216, 0206) and demonstrated in Figure 6. This indicates that there was a decrease in net profit with 50% DDG and WDG. With the $90 DDG, this quadratic affect was also noted for both DDG and WDG (P=.0336,.0153). Currently DG are available at cheaper prices than these in some localities, which would favor feeding the DG at the higher levels, There were no differences in profitability for high to low DG level ( %) vs. low to high DG level ( %). Similar calculations were performed for corn at $2.00 per bushel. With both price intervals, the least profitable diet on a net per head basis was also Treatment 4 (50% DDG) with profits of $24.29 and $49.95, respectfully as shown on Table 8. When DG was purchased at $110/ton DDG and $100/ton WDG, there was a linear decrease with increasing levels of DDG and WDG (P=.0093,.0402). Again 6

81 Distiller Grain Trial Rincker and Berger (2003) with the more expensive DG, there were also a significant quadratic effect among increasing levels of DDG and WDG with a decrease at 50% DG (P=.0262,.0446) and exhibited in Figure 8. Here again, this indicates that there was a decrease in net profit with 50% DDG and WDG. With the $90/ton DDG and $80/ton WDG, this quadratic effect was also significant for both DDG and WDG (P=.0134,.0134) and is shown in Figure 9. These data suggest that the 50% DG diets would be the most profitable only when DG are available at a price lower than corn on a dollars per ton basis. IMPLICATIONS Using recent prices, additions of DDG or WDG at moderate levels (12.5%-37.5%), can improve profitability for a dairy-beef operation. Feeding up to 50% DG, can decrease performance but may be profitable if DG is purchased at a low enough price. There were no differences between switching at 750 lbs from 20 to 37.5% or from 37.5 to 20%. WDG vs. DDG are less palatable, particularly when fed at the high level of 50%. At harvest, there are little differences in overall carcass composition when corn is replaced with DG. This is critical to producers selling cattle on a grid. Additionally, as the level of DG increased so did the level of P and S in the feces. This should be considered in dealing with environmental regulations and manure application rate. Dairy-beef steers should be fed DG at % of the diet for optimum performance, carcass composition and profit margins without having high levels of P and S in the feces. REFERENCES Aines Glen, Terry Klopfenstein and Rick Stock Distillers Grains. Nebraska Cooperative Extension. Publication MP51. DeHaan, K., T. Klopfenstein, R. Stock, S. Abrams and R. Britton Wet distillers byproducts for growing ruminants. Nebraska Beef Cattle Report MP43:33. Farlin, S.D Wet distillers grain for finishing cattle. Anim. Nut. Health 36:35. Firkins, J.L., L.L. Berger, and G.C. Fahey, Jr Evaluation of wet and dry distillers grains and wet and dry corn gluten feeds for ruminants. J. Anim. Sci. 60:847. Firkins, J.L., L.L. Berger, G.C. Fahey, Jr. and N.R. Merchen Ruminal nitrogen degradability and escape of wet and dry distillers grains and wet and dry corn gluten feeds. J. Dairy Sci. 67:1936. Hussein, H.S. and L.L. Berger Feedlot performance and carcass characteristics of Holstein steers as affected by source of dietary protein and level of ruminally protected lysine and methionine. J. Anim. Sci. 73:3503. Hussein, H.S. and L.L. Berger Effects of feed intake and dietary level of wet corn gluten feed on feedlot performance, digestibility of nutrients, and carcass characteristics of growingfinishing beef heifers. J. Anim. Sci. 73:

82 Distiller Grain Trial Rincker and Berger (2003) Lodge, S.L., R.A. Stock, T.J. Klopfenstein, D.H. Shain, and D.W. Herold Evaluation of wet distillers composite for finishing ruminants. J. Anim. Sci : NRC Nutrient Requirements of Beef Cattle. National Academy Press, Washington, D.C. SAS Institute, Inc SAS/STAT User s Guide (Release 6.03). SAS Institute Inc., Cary, NC. Spiehs, M.J., M.H. Whitney, and G.C. Shurson Nutrient database for distiller s dried grains with solubles produced from new ethanol plants in Minnesota and South Dakota. J. Anim. Sci. 80: Trenkle, A., W. Burroughs and G. Rouse Evaluation of corn stillage, corn gluten meal and soybean meal as protein supplements for cattle. Iowa State University, A.S. Leaflet R321. Wertz, A.E., L.L. Berger, P.M. Walker, D.B. Faulkner, F.K. McKeith, and S. Rodriguez-Zas Early weaning and post weaning nutritional management affect feedlot performance of Angus X Simmental heifers and the relationship of 12 th rib fat and marbling score to feed efficiency. J. Anim. Sci. 79:

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86 Summary of Distillers Grains Feeding Recommendations for Swine Based upon research studies we have conducted at the University of Minnesota, our current recommendations for maximum usage rate of DDGS in swine diets are as follows: nursery pigs (>15 lbs), 25%; grow-finish pigs, 20%; developing gilts, 20%; gestating sows, 50%; lactating sows, 20%; boars, 50%. Nursery diets containing up to 25% DDGS will support growth performance equivalent to feeding pigs fed cornsoybean meal based diets Dr. Gerald Shurson and Mindy Spiehs, University of Minnesota, Feeding Recommendations and Example Diets Containing Minnesota-South Dakota Produced DDGS for Swine (DDGS) is an excellent source of digestible phosphorous. Therefore, when adding DDGS to a diet, you will be able to reduce the amount of dicalcium phosphate normally used. 20% is the maximum recommended amount in grow-finish diets. SDSU recommends inclusion rates as outlined by Dr. Gerald Shurson from the University of Minnesota. Bob Thaler, Extension Swine Specialist, Use of Distillers Dried Grains with Solubles (DDGS) in Swine Diets, South Dakota State University Extension Service Extension Extra, ExEx 2035, August 2002 DDGS can be used in nursery, growing-finishing, gestation and lactation diets. The maximum recommended inclusion rate of DDGS in 35- to 250-pound pig diets is 20%. The more acceptable rate is 10% in grow-finish diets. Dr. Gilbert Hollis, Extension Swine Specialist, Distillers Dried Grains with Solubles in Swine Diets, University of Illinois, Illini PorkNet, 2002 The National Corn Growers Association provides these feeding recommendations to assist producers in understanding generally-accepted feeding levels. However, all rations for specific herds should be formulated by a qualified nutritionist. Moreover, the NCGA has no control over the nutritional content of any specific product which may be selected for feeding. Producers should consult an appropriate nutritionist for specific recommendations. NCGA makes no warranties that these recommendations are suitable for any particular herd or for any particular animal. The NCGA disclaims any liability for itself or its members for any problems encountered in the use of these recommendations. By reviewing this material, producers agree to these limitations and waive any claims against NCGA for liability arising out of this material.

87 The Advantages of Using Corn Distillers Dried Grains with Solubles in Swine Diets Corn Distillers Dried Grains with Solubles is an Economical Addition to Swine Diets In one ton of complete feed, adding 200 lbs. of Corn Distillers Grains with Solubles (CCDGS) and 3 lbs. of limestone to a finisher diet will replace approximately: 177 lbs of corn 20 lbs of soybean meal 44% 6 lbs of dicalcium phosphate Calculate the opportunity cost of using CDDGS in swine diets as follows: Additions: + CDDGS 200 lbs. X price/lb = $ + Limestone 3 lbs. X price/lb = $ TOTAL A = $ Subtractions: - Corn 177 lbs. X price/lb = $ - Soybean Meal 44% 20 lbs. X price/lb = $ - Dicalcium Phosphate 6 lbs. X price/lb = $ TOTAL S = $ Opportunity Cost: Total S Total A = Opportunity Cost of CDDGS/lb X 200 lbs/ton = Opportunity cost/ton of complete feed New Generation Ethanol Plants Produce Higher Quality CDDGS CDDGS have more digestible energy, amino acids, and phosphorus than other DDGS sources produced in the ethanol industry. This makes CDDGS an excellent alternative ingredient for livestock rations. CDDGS Can Be Effectively Used in Swine Diets With Maximum Dietary Inclusion Rates of: Nursery Pigs (>15 lbs.) 25% Lactating Sows 10% Grow-finish Pigs 20% Gestating Sows 50% Feeding High Levels of CDDGS to Sows Has Been Shown to Increase Litter Size Weaned Recent research results from the University of Minnesota have shown that feeding high levels of CDDGS in gestation and/or lactation in a previous reproductive cycle, increases litter size weaned in the subsequent reproductive cycle compared to sows fed typical corn-soybean meal diets. 05/19/2004

88 Feeding Diets Containing CDDGS May Improve Gut Health of Pigs Studies are currently underway at the University of Minnesota to determine if adding CDDGS to diets for growing pigs reduces the incidence and severity of ileitis (Lawsonia intracellularis). CDDGS Reduces Phosphorus Excretion in Manure and Does Not Adversely Affect Air Quality in Confinement Swine Facilities CDDGS contains 0.70% available phosphorus (P), which is 18 times more than the available P in corn (0.04%). This means that the natural P in CDDGS is better digested and absorbed by the pig than P in corn and soybean meal. The end result is less need for dietary P supplementation and a reduction in P excretion in manure. University of Minnesota research has shown that ammonia, hydrogen sulfide, and odor emissions from swine manure from grow-finish pigs fed a diet containing CDDGS are the same as when conventional corn-soybean meal based diets are fed to swine. The Greatest Nutritional and Economic Value from Using DDGS in Swine Diets in Achieved when Diets are Formulated on a Digestible Amino Acid and an Available Phosphorus Basis. Nutrient Profiles and Digestibility Coefficients are Available for Each Ethanol Plant Producing CDDGS. For additional information on feeding distillers grains to swine, contact: Dr. Jerry Shurson Dept. of Animal Science University of Minnesota (612) /19/2004

89 Feeding Recommendations and Example Diets Containing Minnesota-South Dakota Produced DDGS for Swine Jerry Shurson and Mindy Spiehs Department of Animal Science University of Minnesota, St. Paul Use Only High Quality DDGS in Swine Diets. Historically, distiller s dried grains with solubles (DDGS) have not been used extensively in swine diets. The primary reasons for this limited use are variability in quality and nutrient content, poor amino acid digestibility from some sources, and cost competitiveness with corn, soybean meal and dicalcium phosphate. However, our research at the University of Minnesota has clearly shown that DDGS produced by small, and relatively new ethanol plants in Minnesota and South Dakota, is very high quality and is an excellent partial substitute for corn, soybean meal, and dicalcium phosphate in swine feeding programs. Distiller s dried grains with solubles from Minnesota and South Dakota plants is higher in digestible and metabolizable energy, higher in total and digestible amino acids, and higher in available phosphorus compared to other DDGS sources and values listed in NRC (1998). Use of low quality, dark colored DDGS has reduced feeding value and pig performance may be reduced if the lower levels of digestible nutrients are not considered in diet formulation. What Are the Recommended Maximum Inclusion Rates of DDGS in Swine Diets? Based upon research studies we have conducted at the University of Minnesota, our current recommendations for maximum usage rate of DDGS in swine diets are as follows: Production Phase Maximum % of Diet Nursery pigs (>15 lbs) 25 Grow-finish pigs 20 Developing gilts 20 Gestating sows 50 Lactating sows 20 Boars 50 These recommendations assume that high quality DDGS is free of mycotoxins. Nursery diets containing up to 25% DDGS will support growth performance equivalent to feeding pigs fed corn-soybean meal based diets provided that diets are formulated on a digestible amino acid and available phosphorus basis. Similarly, grow-finish and gilt development diets containing levels up to 30% DDGS should provide equivalent growth performance compared to pigs fed cornsoybean meal diets if they are formulated on a digestible amino acid and available phosphorus basis. However, due to concerns of reduced belly firmness and soft pork fat at high levels of DDGS inclusion, we recommend no more than 20% DDGS be added to grow-finish diets. If the DDGS supplier has a quality control program that includes screening corn and/or DDGS for 1

90 mycotoxins, developing gilt diets can contain up to 20% DDGS in the diet. For sows, up to 50% DDGS can be successfully added to gestation diets, and 20% DDGS can be added to the lactation diet if DDGS is free of mycotoxins. If there are no assurances that DDGS is mycotoxin free, no more than 20% should be added to gestation diets and no more than 10% DDGS should be added to lactation diets to minimize the risk of mycotoxicosis. However, when switching sows from a corn-soybean meal diet to diets containing DDGS, formulate gestation diets to contain 20% DDGS and then increase DDGS inclusion level when each new batch of feed is made to allow the sows to adapt to the DDGS diets and avoid reduced feed intake. Similarly, when switching from a corn-soybean meal diet to a DDGS diet for lactating sows, begin feeding a 10% DDGS diet to allow the sows to adapt (approximately 5 to 7 days) before feeding the maximum recommended level to allow the sows to adapt to the DDGS diet and avoid potential reductions in feed intake. How Should I Formulate Diets Containing DDGS to Obtain Optimal Performance and Value? Our research results have shown that energy and amino acid digestibility, as well as phosphorus availability of DDGS produced in Minnesota and South Dakota ethanol plants, is higher than nearly all of the values reported in NRC (1998) Nutrient Requirements of Swine and values we obtained from evaluating low quality DDGS (Table 1). Our apparent digestible amino acid and available phosphorus nutrient values should be used to formulate practical diets for all phases of production to ensure that the maximum nutritional value of DDGS is obtained, and that optimal performance is achieved, particularly when adding more than 10% DDGS to any swine diet. Formulating diets using total amino acid and phosphorus values may provide acceptable performance at low inclusion rates (< 10%) of DDGS in swine diets, but will not capture the full nutritional value of DDGS. 2

91 Table 1. Comparison of Nutrient Content, Apparent Amino Acid Digestibility, and Phosphorus Availability of MN/SD DDGS, a Low Quality DDGS Source, and NRC (1988). Nutrient* MN/SD DDGS Low Quality DDGS NRC (1998) Dry matter, % Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Available phosphorus, % 0.80? 0.64 Digestible energy, kcal/kg 3,965 3,874 3,441 Metabolizable energy, kcal/kg 3,592 3,521 3,032 Lysine, % App. digestible lysine, % Methionine, % App. digestible methionine, % Threonine, % App. dig. threonine, % Tryptophan, % App. dig. tryptophan, % * Values expressed on a 100% dry matter basis. Are There Any Concerns in Feeding DDGS to Swine? Quality Historically, grain co-products like DDGS have been treated as commodities in the market place. However, like all co-products, there is large variation in the quality of DDGS available for livestock feeds. Cromwell et al. (1993) conducted a study to compare physical, chemical, and nutritional characteristics of nine different sources of DDGS for chicks and pigs. The color of these sources ranged from very light to very dark, and odor ranged from a sweet smell to smoky or burnt smell. There was also a wide range in nutrient concentration among DDGS sources. Ranges in nutrient concentration of selected nutrients were: Dry matter 87 to 93% Crude protein 23 to 29% Crude fat 3 to 12% Ash 3 to 6% Lysine 0.59 to 0.89% Lysine concentration tended to be highest in light-colored DDGS and lowest in the darkestcolored DDGS sources. When the four darkest, burnt smelling sources were fed to chicks, growth rate, feed intake, and feed conversion were reduced 18 %, 13%, and 6 %, respectively, 3

92 compared to chicks fed the lightest-colored DDGS. Results from this study suggest that DDGS that is dark in colored and/or has a burnt smell should not be used in swine or poultry diets. Source: Cromwell, G.L., K.L. Herkleman, and T.S. Stahly Physical, chemical, and nutritional characteristics of distiller s dried grains with solubles for chicks and pigs. J. Anim. Sci. 71: In order to differentiate DDGS sources that are suitable for swine and poultry diets from other nutritionally inferior sources, the Minnesota and South Dakota ethanol plants have established nutrient specifications and recommended physical characteristics when selecting DDGS sources for swine and poultry diets. Minnesota-South Dakota Nutrient Specifications and Physical Characteristics for DDGS in Swine and Poultry Diets Nutrient specifications Moisture maximum 12% Crude protein minimum 26.5% Crude fat minimum 10% Crude fiber maximum 7.5% Physical characteristics Pork fat quality Bulk density 34 to 37 lb/cubic foot Particle size: maximum coarse particles - 10% on 2000 screen maximum fine particles - 15% on 600 screen & in pan Smell fresh, fermented Color goldenrod Our studies have shown that when feeding DDGS to grow-finish pigs ( lbs), the oil present in DDGS will make pork carcass fat softer and more oily with increasing levels of DDGS in the diet. Similar effects have been shown when adding any high oil grain or grain co-product to swine grow-finish diets. Although softer fat and reduced belly firmness are a concern for packers and meat processors, there currently are no price penalties for pork producers for marketing pigs with reduced pork fat quality. Results from our studies show that feeding up to 20% DDGS in grow-finish diets has no effect on belly thickness or belly firmness score compared to carcasses from grow-finish pigs fed conventional corn-soybean meal diets. Mycotoxins The incidence of documented cases of mycotoxicosis from feeding DDGS to swine is extremely low. However, corn is susceptible to molds that can produce mycotoxins prior to harvest, as well as during storage. The primary mycotoxins of concern to swine are zearalenone, vomitoxin 4

93 (deoxynivalenol), T-2 toxin, fumonisin, and aflatoxins. In the Midwestern U.S., zearalenone and vomitoxin are the greatest risks. If corn containing mycotoxins is delivered to an ethanol plant for ethanol production, these mycotoxins are not destroyed or inactivated during the fermentation process and will be present in DDGS produced from this corn source. In fact, the concentration of mycotoxins in DDGS will be 2 to 3 times higher than the initial concentration in the grain because the removal of starch during the fermentation process concentrates all of the unfermentable residual portions of the grain that remain after fermentation. Ethanol plants are encouraged to monitor incoming corn for mycotoxins and reject loads that are contaminated to prevent mycotoxins in DDGS. Buyers of DDGS are encouraged to work with their suppliers to establish a quality control protocol for the production of DDGS that should include screening tests and procedures for mycotoxins. Feed intake Our studies have shown that feeding nursery and grow-finish pigs diets containing up to 25-30% DDGS from a high quality source has no detrimental effect on feed consumption. However, abruptly switching gestating sows that are being fed 4 to 5 lbs per day of corn-soybean meal based diet to a diet containing 50% DDGS can cause sows to not consume all of the feed offered for a period of 5 to 7 days. After sows have adapted to the 50% DDGS diet, feed consumption and weight gains are equivalent to sows fed a conventional corn-soybean meal diet. We have observed a similar response when feeding lactating sows a diet containing 20% DDGS. Although our preliminary results suggest no negative effects on reproductive performance from this slight reduction in feed intake during this diet adaptation period, it can be avoided by feeding lower levels of DDGS initially and then gradually increasing the inclusion rate of DDGS to a higher, desired level for the duration of the production phase. 5

94 Calculating the Value of New Generation DDGS in Swine Diets Using Soybean Meal 46% Additions/1000 kg diet kg DDGS x cost/kg = $ kg limestone x cost/kg = $ TOTAL ADDITIONS (A) = $ Subtractions /1000 kg diet 89 kg corn x cost/kg = $ 9.5 kg SBM (46%) x cost/kg = $ 3 kg dicalcium phosphate x cost/kg = $ TOTAL SUBTRACTIONS (S) = $ S A = Opportunity cost for DDGS/100 kg Calculating the Value of New Generation DDGS in Swine Diets Using Soybean Meal 44% Additions/1000 kg diet kg DDGS x cost/kg = $ kg limestone x cost/kg = $ TOTAL ADDITIONS (A) = $ Subtractions /1000 kg diet 88.5 kg corn x cost/kg = $ 10 kg SBM (44%) x cost/kg = $ 3 kg dicalcium phosphate x cost/kg = $ TOTAL SUBTRACTIONS (S) = $ S A = Opportunity cost for DDGS/100 kg 6

95 Nursery Diets Phase II (15-25 lbs) Diet 0% DDGS 5% DDGS 10% DDGS 15% DDGS 20% DDGS 25% DDGS DDGS Corn SBM, 47% Whey, dried IPC 790 fish meal Choice white grease Dicalcium phosphate Limestone Vitamin premix Trace mineral premix Mecadox Zinc oxide Salt L-lysine DL-methionine Total Nutrient Composition ME (kcal/kg) Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Avail. phosphorus, % App. dig. lysine, % App. dig. met+cys, % App. dig. threonine, % App. dig. tryptophan, %

96 Phase III (25-50 lbs) Diet 0% DDGS 5% DDGS 10% DDGS 15% DDGS 20% DDGS 25% DDGS DDGS Corn SBM, 47% Choice white grease Dicalcium phosphate Limestone Vitamin premix TM premix Mecadox Copper sulfate Salt L-lysine DL-methionine Total Nutrient Composition ME (kcal/kg) Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Avail. phosphorus, % App. dig. lysine, % App. dig. met+cys, % App. dig. threonine, % App. dig. tryptophan, %

97 Grow-Finish Diets ( lbs) Grower 1 Grower 2 Finisher 1 Finisher 2 Gilt Diets (45-80 lbs) ( lbs) ( lbs) ( lbs) Diet 10% DDGS 10% DDGS 10% DDGS 10% DDGS DDGS Corn SBM, 47% Choice white grease Dicalcium phosphate Limestone Vitamin premix Trace mineral premix Salt L-lysine Total Nutrient Composition ME (kcal/kg) Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Avail. Phosphorus, % App. dig. lysine, % App. dig. met+cys, % App. dig. threonine, % App. dig tryptophan, %

98 Grower 1 Grower 2 Finisher 1 Finisher 2 Gilt Diets (45-80 lbs) ( lbs) ( lbs) ( lbs) Diet 20% DDGS 20% DDGS 20% DDGS 20% DDGS DDGS Corn SBM, 47% Choice white grease Dicalcium phosphate Limestone Vitamin premix Trace mineral premix Salt L-lysine Total Nutrient Composition ME (kcal/kg) Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Avail. phosphorus, % App. dig. lysine, % App. dig. met+cys, % App. dig. threonine, % App. dig. tryptophan, %

99 Grower 1 Grower 2 Finisher 1 Finisher 2 Barrow Diets (45-80 lbs) ( lbs) ( lbs) ( lbs) Diet 10% DDGS 10% DDGS 10% DDGS 10% DDGS DDGS Corn SBM, 47% Choice white grease Dicalcium phosphate Limestone Vitamin premix Trace mineral premix Salt L-lysine Total Nutrient Composition ME (kcal/kg) Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Avail. phosphorus, % App. dig. lysine, % App. dig. met+cys, % App. dig. threonine, % App. dig. tryptophan, %

100 Grower 1 Grower 2 Finisher 1 Finisher 2 Barrow Diets (45-80 lbs) ( lbs) ( lbs) ( lbs) Diet 20% DDGS 20% DDGS 20% DDGS 20% DDGS DDGS Corn SBM, 47% Choice white grease Dicalcium phosphate Limestone Vitamin premix Trace mineral premix Salt L-lysine Total Nutrient Composition ME (kcal/kg) Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Avail. phosphorus, % App. dig. lysine, % App. dig. met+cys, % App. dig. threonine, % App. dig. tryptophan, %

101 Example Grower Diet Containing 20% DDGS and 100 FTU Phytase/kg Ingredient % Corn DDGS Soybean meal, 46% Dicalcium phosphate 0.05 Limestone 0.95 Salt 0.30 Vitamin-trace mineral premix 0.15 L-lysine HCl 0.15 Phytase Total Nutrient Composition ME, kcal/kg 3,330 Crude protein, % Calcium, % 0.44 Phosphorus, % 0.43 Avail. phosphorus, % 0.20 App. dig. lysine, % 0.74 App. dig. met+cys, % 0.51 App. dig. threonine, % 0.48 App. dig. tryptophan, %

102 Gestation and Lactation Diets Gestation Gestation Lactation * Lactation * Lactation ** Lactation ** 20% DDGS 50% DDGS 10% DDGS 20% DDGS 10% DDGS 20% DDGS DDGS Corn SBM, 44% Choice white grease Dicalcium phosphate Limestone Breeder vitamin premix Breeder trace mineral premix Salt L-lysine Total Nutrient Composition ME (kcal/kg) Crude protein, % Calcium, % Phosphorus, % Available P, % App. dig. lysine, % App. dig. met, % App. dig. threonine, % App. dig. tryptophan, % * ADFI = 10.5 lbs/d, 21-d litter wt. < 120 lbs ** ADFI = 12.0 lbs/d, 21-d litter wt. > 120 lbs 14

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104 Extension Extra ExEx 2035 August 2002 Animal & Range Sciences COLLEGE OF AGRICULTURE & BIOLOGICAL SCIENCES / SOUTH DAKOTA STATE UNIVERSITY / USDA Use of Distillers Dried Grains With Solubles (DDGS) in Swine Diets Bob Thaler, Extension swine specialist More and more ethanol co-products are available for livestock feed because of the rapid growth of the ethanol industry in South Dakota. The three main co-products are Distillers Grains, Solubles, and Distillers Grains with Solubles, and they can be either wet or dried depending on the manufacturing process. Since, in the U.S., on-farm feed mixing and swine feeding systems are almost exclusively designed for dry feed, we deal here only with the dried products. All ethanol plants in South Dakota mainly produce Distillers Dried Grains with Solubles (DDGS), limiting our discussion further to only DDGS as a feed ingredient for swine. DDGS Corn is two thirds starch, and during the fermentation and distillation processes, the starch is converted to ethanol. One bushel of corn produces approximately 2.6 gallons of ethanol, 17 lbs of CO 2, and a wet spent-mash. The wet mash goes through a series of centrifuges, evaporators, and presses to produce Solubles (liquid) and Distillers Grains (semi-dry). The Solubles and Distillers Grains are then blended and dried to produce 17 lbs of DDGS from the same bushel of corn. DDGS is a co-product, and like all co-products (soybean meal, meat and bone meal, sunflower meal), it can vary greatly in nutrient concentrations. Ranges of nutrient concentrations and physical characteristics from nine DDGS samples are given here: Dry matter 87-93% Crude protein 23-29% Crude fat 3-12% Lysine % Color light golden to dark brown Smell sweet to smoky or burnt Growth trials conducted with the nine different DDGS sources demonstrated large differences in gain, feed intake, and feed efficiency, depending on the source of DDGS in the diet. Therefore, DDGS quality has a considerable and variable impact on livestock performance. Why these differences in nutrient concentrations? There are several reasons. First of all, nutrient variability of the corn used has a dramatic impact on the variability of DDGS. Since the starch in corn is converted to ethanol and removed, the remaining nutrients in corn are concentrated and roughly tripled in the resulting DDGS. For example, if a load of corn contains.26% lysine, the resulting DDGS will likely contain.78 % lysine. However, if a lower lysine corn (.23% lysine) is used, the resulting DDGS will contain only.69% lysine. The same

105 rule applies for the concentrations of all the other nutrients (fat, fiber, protein, phosphorus, etc.) The second factor to have a major impact on DDGS nutrient concentrations is processing methods. Type of yeast used, fermenting and distillation efficiency, drying temperature and time, and amount of solubles blended with the dry material all affect the nutrient concentrations in DDGS. Recent research at the University of Minnesota also has shown that DDGS from the new-generation ethanol plants in South Dakota and Minnesota has higher nutrient concentrations than DDGS from traditional ethanol plants. Table 1 shows the nutrient composition of traditional and new generation DDGS. Table 1. Nutrient composition of two sources of DDGS (as-fed basis). Traditional SD/MN Nutrient DDGS DDGS Crude Protein 27.7% 26.8% Total lysine.62%.74% Digestible lysine.29%.39 Crude fat 8.4% 9.7% Crude fiber 9.1% 7.8% Calcium.20%.05% Total phosphorus.77%.79% Digestible phosphorus.59%.71% Metabolizable energy, kcal/lb Table 1 shows large differences in nutrient concentrations for the processing methods, especially for two of the most critical nutrients: digestible lysine (34.5%) and digestible phosphorus (20.3%). The question then becomes What values do I use when formulating swine rations? The best answer is to properly sample each load of DDGS you get and analyze for lysine and phosphorus. Then multiply those values by their digestibility coefficients (lysine =.53; phosphorus =.90) to get the amount digestible of each nutrient. For example, if a sample of DDGS contained.80% total lysine and.78 total phosphorus, you d multiply.80% times.53 to get a digestible lysine value of.42%. Then, multiply.78% by.90 to get a digestible phosphorus concentration of.702%. These are the values you need to use when balancing swine rations. If analyzing each load of DDGS is not feasible, the next best thing to do is to visit the plant you purchased the 2 DDGS from and find out the nutrient range of its product over the last 6 months. To avoid a potential nutrient deficiency, it is then best to select a value at the lower end of each range to use when formulating. If that data is not available, consider changing suppliers or use the values for traditional DDGS. Another method to reduce nutrient variation is to develop a DDGS specification sheet for nutrient levels and physical characteristics, and then only buy DDGS from plants that will guarantee meeting those specifications. However, you are responsible for periodic testing to ensure your specifications are being met. Table 2 is one example of such a sheet. Table 2. Specifications for DDGS for swine diets. Moisture maximum 12% Crude protein minimum 26.5% Crude fat minimum 10% Crude fiber maximum 7.5% Color golden Smell fresh, fermented, pleasant cereal odor Bulk density lb/cubic foot Particle size coarse = 10% maximum on a mesh screen fine = 15% maximum on a 600-mesh screen and pan Mycotoxins Mycotoxins are produced by molds either in the field or during storage. They can severely impact pig and sow performance. While there are many different mycotoxins, zearalenone and vomitoxin (DON) are the main ones of concern for South Dakota pork producers. Unfortunately, the fermentation process does not destroy mycotoxins. In fact, just as it does for lysine and other nutrients, it concentrates the mycotoxins threefold. If corn containing 1 ppm zearalenone is delivered to an ethanol plant, the resulting DDGS will contain 3 ppm zearalenone. Since the maximum inclusion rate of both mycotoxins is 1 ppm in the total diet, it does not take a large amount of mycotoxins to cause problems, especially for sows. This is more of a problem if the ethanol plant is purchasing damaged grains or if it has been a year in which there has been a mycotoxin problem in the corn in the field.

106 If you suspect a problem, send a DDGS sample to an analytical lab for a mycotoxin analysis. Or you can purchase DDGS only from ethanol plants that do not buy damaged grains. Visit with each plant manager to learn the plant s policy on purchasing mycotoxin-contaminated grains. While damaged corn will not have much negative impact on ethanol production, it could have a great impact on the mycotoxin levels in the DDGS. Also, even in the best quality-control systems, some damaged corn can get in. Therefore, it is strongly recommended to start conservatively when including DDGS in gestation and lactation diets. Incorporating DDGS into swine diets Pigs require amino acids, not protein, so swine diets need to be balanced on a lysine or digestible lysine basis, not on crude protein. While DDGS is relatively high in protein, it is still low in lysine, the first limiting amino acid for swine in grain-based diets. Due to its poor amino acid balance for pigs, corn is a poor quality protein source for pigs. When corn is processed into DDGS, the poor amino acid balance is concentrated, not improved in DDGS. Therefore, to properly incorporate DDGS in swine diets, the diets must be formulated on a lysine or digestible lysine basis. If the diets are balanced on crude protein, the diets will be grossly deficient in lysine and other essential amino acids, and pig performance will be substantially decreased. Keep in mind that DDGS is not just another amino acid source. It is also an excellent source of digestible phosphorus. Therefore, when adding DDGS to a diet, you will be able to reduce the amount of dicalcium phosphate normally used. As was mentioned before, source of DDGS is critical on pig performance. The recommendations in Table 3 are based on a high quality DDGS and on diets balanced on digestible lysine and phosphorus. It is recommended to start at the lower inclusion level and then gradually work your way up to the maximum inclusion rate, especially for sows. University of Minnesota has shown that going immediately to the higher levels for sows resulted in an initial reduction in feed intake for about 1 week before they went back to full feed. Also, 3 Table 3. Recommended inclusion rates of DDGS in swine diets. Starting Maximum Phase point inclusion rate Nursery (>15 lbs) 5% 25% Grow-finish 10% 20% Gestating sows 20% 50% Lactating sows 5% 20% Boars 20% 50% mycotoxins have the greatest effects on reproduction, so extra care must be taken when using DDGS in sow diets. DDGS concentrations up to 30% of the diet have no effect on grow-finish pig performance. However, the 30% inclusion level does result in carcasses that have reduced belly firmness and more soft fat due to the high concentrations of polyunsaturated fatty acids in DDGS. Therefore, 20% is the maximum recommended amount in grow-finish diets. Storage DDGS contains approximately 10% fat, and a large portion of that fat is composed of polyunsaturated fatty acids. Since polyunsaturated fatty acids are subject to rancidity, you will need to use DDGS as quickly as possible. It is recommended that you buy no more than a 3-month supply of DDGS in the winter and no more than a 1-month supply in the summer. Due to its high fat content, DDGS flowability through bulk bins may be a potential problem. Use caution when selecting the facility to store DDGS in on-farm. Health benefits There have been reports by producers that 10-20% DDGS in grow-finish diets reduces the incidence/severity of ileitis and Hemorrhagic Bowel Syndrome (HBS). However, no controlled research trials have been conducted to demonstrate this effect. SDSU and the University of Minnesota are currently conducting such trials, but we have no data to offer at this point. Therefore, use caution in applying any economic value to DDGS s health effects until the trials are completed.

107 Economics DDGS provides lysine, phosphorus, and energy, and it replaces soybean meal, dicalcium phosphate, and corn. When considering the economics of using DDGS, all these factors must be included. As a rule of thumb, 200 lb of DDGS and 3 lb of limestone can replace 178 lb of corn, 19 lb of 46% protein soybean meal, and 6 lb of dicalcium phosphate in a ton of complete feed. However, by balancing on a digestible amino acid basis and making certain all ten essential amino acid requirements are being met, higher concentrations of DDGS can be used in swine diets. Table 4. Determine the approximate worth of DDGS in your swine diets. Ingredients $/lb Lb Total cost DDGS Limestone Corn SBM (46% CP) Dical Phos (18.5% P) Total cost, $ If DDGS is $85/ton ($.043/lb), 46% SBM is $245/ton ($.123/lb), corn is $2.37/bu ($.042), limestone is $.013/lb, and dical phos is $.15/lb, you can calculate the worth of 200 lb of DDGS. Table 5. The worth of 200 lb of DDGS. Current Ingredients $/lb Lb DDGS cost cost DDGS Limestone Corn SBM (46% CP) Dical Phos (18.5% P) Total cost, $ $8.64 $ In this example, a 10% inclusion of DDGS (200 lb/ton) would save $2.08/ton of feed. Assuming that it takes three pigs to consume one ton of feed, using 10% DDGS would reduce diet cost by $.69/pig in this example. For ease of calculation, there is an Excel spreadsheet available at your local county Educator s office and also on the Animal and Range Sciences Department homepage ( If you properly formulate diets so that the DDGS concentrations do not exceed the maximum recommended levels, the decision to use DDGS depends on which complete diet is less expensive corn-sbm or corn-sbm-ddgs. Summary DDGS is a co-product from the ethanol industry and is a source of amino acids and phosphorus for swine. Producers must be aware of the wide range of nutrients and potential mycotoxin problems associated with DDGS. However, a proper analysis or screening program can alleviate those concerns. DDGS can work well in swine rations at the proper inclusion level when the diets are balanced on digestible amino acids and phosphorus. Once that is done, the decision to use DDGS or not depends on economics. For further information on DDGS, please contact your local county educator or Bob Thaler at (Robert_thaler@sdstate.edu). This publication and others can be accessed electronically from the SDSU College of Agriculture & Biological Sciences publications page at or the Extension Service Drought Information Website at Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the USDA. Larry Tidemann, Director of Extension, Associate Dean, College of Agriculture & Biological Sciences, South Dakota State University, Brookings. SDSU is an Affirmative Action/Equal Opportunity Employer (Male/Female) and offers all benefits, services, and educational and employment opportunities without regard for ancestry, age, race, citizenship, color, creed, religion, gender, disability, national origin, sexual preference, or Vietnam Era veteran status. ExEx 2035: 150 copies printed by CES at a cost of 12 cents each. August 2002.

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109 Distillers Dried Grains with Solubles in Swine Diets Gilbert R. Hollis Extension Swine Specialist Department of Animal Sciences University of Illinois Distillers grains are by-products of when grains are fermented into alcohol. The spent grains are dried and sold as feed. Solubles left over from fermentation usually are added to the distillers grains (DDG) before drying, resulting in a product called distillers dried grains with solubles (DDGS), the most common commercial product. Distillers grains are identified by the type of grain from which they are made, i.e. corn distillers, milo distillers, or other grains (wheat or rye). Distillers Dried Grains with solubles (DDGS) is the product obtained by condensing and drying the stillage that remains after fermenting the starch in corn or milo in the production of ethyl alcohol. There is renewed interest in feeding DDGS to swine because the rapid growth of the ethanol industry in the Midwest has increased the quantity and local supply. Historically, DDGS has not been used in swine diets because of the low protein quality (poor amino acid balance), low amino acid digestibility, high fiber content and the nutrient variability among sources. This left an image of an inferior ingredient for swine diets. Today, according to University of Minnesota research the new ethanol plants are producing DDGS with higher nutrient content and digestibility than that listed in the 1998 National Research Council publication on Nutrient Requirements of Swine. Nutrient Profile When compared to corn, the typical energy source used in Midwestern swine diets, the nutrient profile of DDGS varies slightly. Distillers' grains has higher protein (25 to 30 %), fat (8 to 10 %), and fiber (4 to 12 %) content than corn due to the fermentation process removing the starch component. Distillers' by-products do have several features that limit their use in swine diets. The high fiber content may cause diarrhea in young pigs. Distillers' grains will have a lower metabolizable energy content due to less starch. The crude protein content is relatively high, but the amino acid profile is not well balanced. For example, distillers' grains are quite low in lysine content (0.6 to 0.9 %). Therefore, swine diets containing distillers' dried grain with solubles (DDGS) need to be formulated on a digestible lysine and energy basis. Formulating the diet on a crude protein basis will result in a lysine deficiency and possible a deficiency of other amino acids, such as tryptophan, methionine or threonine, which will reduce growth performance. Growth Performance DDGS can be used in nursery, growing-finishing (G-F), gestation and lactation diets. Several research studies have reported favorable results in growth and feed efficiency of pig when fed 2.5 to 5% of DDGS. The maximum recommended inclusion rate of DDGS in 35 to 250 pound pig diets is 20%. The more acceptable inclusion rate is 10% in G-F diets. When the

110 20% inclusion rate is used then synthetic lysine and tryptophan should be added to maintain an amino acid balanced diet with adequate growth performance. Recommended Maximum Inclusion Rates of DDGS in Swine Diets Based upon research studies conducted at the University of Minnesota over the last three years, the recommended maximum usage rate of DDGS in swine diets are as follows (Assuming that high quality DDGS is free of mycotoxins): Production Phase Maximum % of Diet Nursery pigs (> 15 lbs) 5 Growing pigs ( lbs) 10 Finishing pigs ( lbs) 20 Developing Gilts 20 Gestating sows 50 Lactating sows 20 Boars 50 Table 1 gives a comparison of nutrient content, apparent amino acid digestibility, and phosphorus availability of MN/SD DDGS, a low quality DDGS source, and NRC (1998). Table 1. Comparison of Nutrient Content, Apparent Amino Acid Digestibility, and Phosphorus Availability of MN/SD DDGS, a Low Quality DDGS Source, and NRC (1998). a Nutrient* MN/SD DDGS Low Quality DDGS NRC (1998) Dry matter, % Crude protein, % Crude fat, % Crude fiber, % Calcium, % Phosphorus, % Available phosphorus, % Digestible energy, kcal/kg Metabolizable energy, kcal/kg Net energy, kcal/kg Lysine, % App. digestible lysine, % Methionine, % App. digestible methionine, % Threonine, % App. digestible threonine, % Tryptophan, % App. digestible tryptophan, % ,965 3, ? 3,874 3, ( NRC) ,200 2,820 2, a Source: Feeding recommendations and Example Diets Containing MN/SD Produced DDGS for Swine. Jerry Shurson and Mindy Speihs, Department of Animal Science, University of Minnesota

111 Cautions in Feeding DDGS to Swine 1. Quality a. There is a large variation in the quality of DDGS available for swine feeds. Golden color DDGS is much better suited for swine diets than darker colored DDGS due to higher amino acid digestibility. b. Odor ranges form sweet to smoky to burnt c. According to research at the University of Minnesota, DDGS produced by new Midwestern plants is higher in nutrient content and digestibility (Table 1) than DDGS from older plants. d. Quality considerations for selecting DDGS sources; Nutrient Specifications Moisture maximum 12% Protein minimum 26.5% Fat minimum 10% Fiber maximum 7.5% 2. Nutrient variability of Midwestern DDGS sources a. Dry matter 87 to 93% b. Crude protein 23 to 29% c. Crude fat 3 to 12% d. Ash 3 to 6% e. Lysine 0.59 to 0.89% 3. Pork fat quality University of Minnesota studies have shown that when feeding DDGS to G-F pigs ( lbs), the oil present in DDGS will make pork carcass fat softer and more oily with increasing levels of DDGS in the diet. These same studies showed that feeding up to 20% DDGS in G-F pig diets had no effect on belly thickness or belly firmness score compared to carcasses from G-F pigs fed conventional cornsoybean meal diets. 4. Mycotoxins Corn is susceptible to molds that can produce mycotoxins prior to harvest, as well as during storage. The primary mycotoxins of concern to swine are zearalenone, vomitoxin (deoxynivalenol), T-2 toxin, fumonisin, and aflatoxins. In the Midwestern U.S., zearalenone and vomitoxin are the greatest risk. 5. Amino acid digestibility is reduced in dark colored DDGS. 6. High fiber limits its use in pre-starter diets (< 15 lb livewight) 7. Because of the high fiber content, sows will take twice as long to eat their daily feed allotment than sows fed a corn-soybean meal diet.

112 Maximizing the Value of DDGS in Swine Diets 1. Excess nitrogen can be minimized by using synthetic amino acids. 2. Dietary inclusion rates should be gradually increased in gestation (up to 40%) and lactation (up to 20%) diets to allow sows to adapt. 3. Formulate diets using digestible amino acid values. 4. High available phosphorus reduces the level of dietary phosphorus supplementation. Feeding Recommendations For feeding recommendations and example diets containing DDGS for all classes of swine contact Dr. Gilbert Hollis, 1207 West Gregory Drive, Urbana, IL 61801; g- or see the following University of Minnesota web site:

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116 Summary of Distillers Grains Feeding Recommendations for Poultry Corn distillers dried grains with solubles can contribute energy, protein and phosphorous to poultry diets. Maximum dietary inclusion levels: broilers, 10%; turkeys (grow-finish), 15%; chicken layers, 15%. Higher levels may be used but may require more careful adjustment of amino acid and energy levels. Dr. Sally Noll, University of Minnesota, Corn Distillers Dried Grains with Solubles for Poultry, prepared for Minnesota Corn Growers Association, 2005 Distillers dried grains plus solubles proved to be a successful feed ingredient when used up to 15% in commercial laying hen diets. B.S. Lumpkins, A.B. Batal and N.M. Dale, University of Georgia, The Use of Distillers Dried Grains Plus Solubles (DDGS) for Laying Hens, 2005 Journal of Applied Poultry Research 14:25-31 Based on trial diets of 6, 12 and 18% DDGS, the new generation DDGS evaluated is a highly acceptable feed ingredient for broiler chickens. B.S. Lumpkins, A.B. Batal and N.M. Dale, University of Georgia, Evaluation of Distiller s Dried Grains with Solubles as a Feed Ingredient for Broilers, presented at Southern Poultry Science Meeting, 2003 Results indicate that ethanol-derived DDGS can be effectively included at 10% in growing/finishing diets for turkey hens if proper formulation matrix values for all nutrients re used. Kevin D. Robertson, Michigan State University, Use of Dried Distillers Grains with Solubles in Growingfinishing Diets of Turkey Hens, International Journal of Poultry Science 2 (6): , 2003 The National Corn Growers Association provides these feeding recommendations to assist producers in understanding generally-accepted feeding levels. However, all rations for specific herds should be formulated by a qualified nutritionist. Moreover, the NCGA has no control over the nutritional content of any specific product which may be selected for feeding. Producers should consult an appropriate nutritionist for specific recommendations. NCGA makes no warranties that these recommendations are suitable for any particular herd or for any particular animal. The NCGA disclaims any liability for itself or its members for any problems encountered in the use of these recommendations. By reviewing this material, producers agree to these limitations and waive any claims against NCGA for liability arising out of this material.

117 Corn Distiller Dried Grains with Solubles for Poultry -An economical addition to poultry diets Corn Distiller Dried Grains with Solubles (CDDGs) can contribute energy, protein and phosphorus to poultry diets. Least cost formulation will allow up to 20% CDDGs when the product is priced between $75 to 110 per ton depending on cost of other ingredients corn, SBM, supplemental fat, supplemental lysine and dicalcium phosphorus -High quality product is available As a source of protein: Current research indicates that the nutrient quality of CDDGS is much improved over past nutrient listings. Digestible lysine content can be as high as 83% as compared to NRC (Nutrient Requirements for Poultry, 1994) value of 65%. 1 As a source of phosphorus: CDDGs is quite high in phosphorus ( %) and research indicates that the phosphorus is at least 65% bioavailable. 2 As a source of energy: Recent research has found a value of 1283 kcal/lb of true metabolizable energy (TME) for both turkeys and chickens and an apparent metabolizable energy (AME) content of 1250 kcal/lb. Values of 1300 kcal/lb have been used in feeding trials with turkeys without effect on feed conversion 3 and values of 1350 kcal/lb in chicken layer and broiler studies 4. A minimum suggested metabolizable energy (ME) value of 1250 kcal/lb should be used in feed formulation. As a source of xanthophylls: CDDGS contributes to pigmentation of egg yolk and chicken carcasses. Feeding of 10% CDDGS darkened egg yolks within one month of feeding in corn-soybean meal based diets. -Maximum dietary inclusion levels Broilers 10% Turkeys (grow/finish) 15% Chicken Layers 15% Higher levels may be used but may require more careful adjustment of amino acid and energy levels 1 University of Minnesota and University of Illinois 2 University of Illinois 3 University of Minnesota and Michigan State University 4 University of Georgia

118 -Keys to CDDGs use in poultry diets Obtain current analytical information from the source of the material as plants are producing a relative consistent product. Formulate diets considering amino acid digestibility especially for lysine, cystine, and threonine Formulate diets using minimums for tryptophan and arginine in addition to lysine, TSAA, and threonine, due to the potentially limiting nature of these amino acids in corn DDGs protein Lower levels of inclusion should be used in diets of young poultry or when first introduced into the diet. Consider using a higher ME value than that currently recommended by NRC (1994) which lists a ME value of 1130 kcal/lb for DDGs. As most corn DDGs has a fat content which exceeds 9%, ME for CDDGs should be higher, at least in the range of kcal/lb. For more information on DDGS research and utilization of DDGs in poultry diets, visit the University of Minnesota website on DDGs at Or contact Dr. Sally Noll Department of Animal Science University of Minnesota 1364 Eckles Ave St. Paul, MN nollx001@umn.edu UPDATED OCTOBER, 2005.

119 DISTILLERS GRAINS IN POULTRY DIETS S. Noll, V. Stangeland, G. Speers and J. Brannon University of Minnesota Anticipation of increased supplies of distiller s dried grains with solubles (DDGS) in the Midwest has rekindled the interest in utilization of this by-product in animal feeds. In the Midwest US, corn is the primary feed stock although other grains can be processed as well. With increasing numbers of chicken layers and a large turkey industry in the Midwest, use of DDGS in poultry diets appears to have potential. Unfortunately, there is limited recent research for this ingredient with modern strains of poultry. In the dry mill production of ethanol two products are produced liquid solubles and grain residue. Each could be dried separately but are mixed together to form DDGS as a dry ingredient. Some of the liquid solubles have been fed experimentally with acceptable results (Hunt et al., 1997) but usually the product is fed after drying. DDGS as a feed ingredient has a moderate protein content and energy level similar to soybean meal. As a sole source of protein in diet, Parsons and coworkers (1983) found DDGS to be limiting in tryptophan and arginine after lysine. An early use of DDGS in poultry diests was primarily as a source of unidentified factors that promote growth and hatchability. Distillers dried solubles (DDS) or DDGS were used in diets at low levels of inclusion usually less than 10%. Couch et al. (1957) found 5% inclusion of DDS variably improved turkey growth rates with the response ranging from 17-32%. Day et al (1972) reported broiler body weight improvements to DDS and DDGS in broiler diets at 2.5 and 5% in one of 3 trials. Improved reproductive performance has also been indicated for turkey breeder hens. Couch et al (1957) found improvements in turkey breeder hatchability during the second half of lay with inclusion of dried alfalfa meal, condensed fish solubles, and DDS. Manley et al (1978) found 3% DDGS improved egg production in hens late in lay and experiencing a low rate of egg production. In diets low in phosphorus DDGS was particularly valuable in improving egg production. However, in a subsequent report, no benefits were observed without low dietary phosphorus (Grizzle et al., 1982). Some have hypothesized that the UGF response may partially be due to alteration of feed palatability. Alenier and Combs (1981) noted chicken layer hens preferred rations containing 10% DDGS or 15% DDS over a corn-soy diet without DDGS. Cantor and Johnson (1983) were unable to document an effect with distillers in corn soy diets for young chicks. With identification of essential nutrients and availability of commercial supplements, UGF sources are often looked upon with skepticism (Leeson and Summers). Use of DDGS has also been examined at high levels of inclusion. When lysine levels were adjusted in turkey diets, similar body weights were obtained with DDGS inclusion up to 20% of the diet to 8 wks of age; but feed conversion worsened (Potter, 1966). Parsons et al. (1983) found that DDGS could replace up to 40% of soybean meal protein when lysine content was adjusted without an effect on body weight. When energy is also adjusted body weights and feed conversions are not affected by inclusion of distillers to high levels. Waldroup et al (1981) included DDGS to 25% of diet for broilers. When adjusted for lysine and energy level,

120 performance was not affected. Without adjustment for energy, growth was maintained but feed conversion decreased. Caloric intake per gain was similar across all treatments. Despite the above research results, nutritionists are hesitant to use high inclusion levels in the diet. The lower energy (less starch) and higher fiber content is a concern and high dietary levels may limit intake of high performance meat poultry. Variability in product nutrient content and quality is often cited. Indeed, variability exists in nutrient content and performance response. In the report presented by Cromwell and coworkers (1993), 9 different samples of DDGS were analyzed and tested in chick diets. A large range of lysine contents were noted (.43 to.89%). Chick responses to inclusion of these same samples (20%) in isonitrogenous and isocaloric diets ranged from 63 to 84% of the corn-soy-starch control. Samples higher in lysine tended to perform better but some samples did not follow this pattern. As distiller grains undergo heating to produce the dried product, concern exists over amino acid digestibility especially for heating of lysine in the presence of sugars. Indeed the limited literature citations indicate poorer availability of lysine. Combs and Bossard (1969) found lysine availability to range from 71-93% by chick growth assay. Parsons et al (1983) found slightly lower availability of 66% by chick growth assay. Lysine digestibility with roosters was found to be 82%. Other sources also assign a low digestibility to DDGS. With the paucity of research and new developments in production of DDGS, inclusion levels and digestibility should be reconsidered. In the Midwest, a variety of ingredients are available and may be cost effective when considering both ingredient cost and effects on performance. Besides soybean meal, meat and bone meal and canola meal is often available. Along with corn and SBM, these ingredients are often used in market poultry diets. Meat and bone meal is a good source of protein and offers other nutrients such as calcium and phosphorus and contributes energy (fat) to the diet. Canola meal has benefits for pellet quality and mill throughput. Utilization of other ingredients such as DDGS needs to be evaluated in such diets with an emphasis on protein quality or amino acid balance as performance and breast meat yield is greatly impacted by intake of specific amino acids. Thus a study was designed to examine if significant levels of canola meal and DDGS can be used in market turkey diets and to determine which amino acids (tryptophan, isoleucine, arginine) may limit performance with diets containing canola and DDGS. Nicholas male poults were placed in starting pens at one day of age and reared to 5 weeks of age. Poults were fed a pre-experimental diet designed for best rate of gain. At 5 weeks of age the birds were randomly distributed into 98 pens with 10 birds per pen. Room temperature at 5 wks was targeted at 70 F. In the other room temperature was gradually decreased to 60 F at 14 wks of age and a minimum of 55 F held for the remaining experimental period. Starting at 5 wks of age, the toms in each environment (cool and warm temperature environments) were fed one of seven dietary treatments with 7 replicates per treatment.

121 Treatments 1. Control - Corn/soy/animal protein 2. As 1 plus corn DDGS 3. As 1 plus Canola meal 4. As 1 plus DDGS and Canola meal 5. As 4 plus Tryptophan to Trt 1 6. As 4 plus Tryptophan and Isoleucine to Trt 1 7. As 4 plus Tryptophan, Arginine, and Isoleucine to Trt 1 All major diet ingredients were analyzed for nutrient content and digestible amino acids (Table 1). Ingredients were chemically analyzed for protein, minerals and amino acids. Samples of each ingredient were submitted to Dr. Parson at the University of Illinois for determination of digestible amino acids using cecatomized chickens. Sample diets are shown in Tables 2 and 3 for the respective 5-8 and wk periods for Treatments 1 through 4. The control diet (Treatment 1) includes animal protein because of its obvious economic advantage and widespread use. Valine content (as a percent of protein) is similar across ingredients; therefore diet protein in these sample diets was fixed by setting a valine specification. Supplemental lysine, methionine, and threonine were used so that all diets contained adequate amounts of these amino acids. For Treatments 5, 6, and 7 supplements of tryptophan, arginine and isoleucine were used to achieve amino acid levels similar to that of Treatment 1. All diets contained 60 gm Coban and 20gm Stafac from 5-8 wks and 20 gm Stafac per ton alone from 8-19 wks of age. Weights and feed consumption were determined at 8, 11, 14, 17 and 19 wks of age. At 19 weeks, toms were processed and carcass and breast meat yield determined. At this time samples of breast meat representing each treatment and environment were measured for meat quality by obtaining color, ph, and purge loss. The experimental design was factorial with diet and environment as the main effects. Analyses of variance were conducted to determine the effects of diet, environment and their interaction on gain, feed conversion, and breast meat yield. Body weight and feed efficiency (feed/gain) were affected primarily by environment temperature. Turkeys grown in the warm temperature environment had less body weight especially at 19 wks of age with somewhat better feed efficiency (Table 4). Inclusion of moderate levels of canola meal and DDGS had no adverse effects on performance in comparison to the control diet in either environment. Both environment and diet (Table 5) affected breast meat yield (amount and percentage). Warm temperatures depressed yield by 1.2 lbs. or 2% of the carcass. Inclusion of either DDGS or canola meal alone had little effect on breast meat yield. However, the inclusion of both into the diet depressed percentage meat yield significantly. Supplementation of the diet with tryptophan restored some of the lost yield in comparison. Isoleucine was without effect, while supplementation with arginine (in combination with tryptophan and isoleucine) restored breast meat yield completely. In summary, digestible amino acid content of the DDGS used in this project was much better than reported elsewhere. Warm environmental temperatures depressed body weights by 1.8 lbs.

122 at 19 wks of age and breast meat amount by 1.2 lbs. Inclusion of significant levels of either canola and/or DDGS had no effect on growth performance. Breast meat yield (as a proportion of carcass weight) was sensitive to amino acid quality as reflected by the depression in yield when the combined diet of canola and distiller grains were fed. The amino acids tryptophan and arginine appeared to play a role in restoring yield. REFERENCES Alenier, J. C., and G. F. Combs, Jr., Effects on feed palatability of ingredients believed to contain unidentified growth factors for poultry. Poultry Sci. 60: Cantor, A. H., and T. H. Johnson, Effects of unidentified growth factor sources on feed preference of chicks. Poultry Sci. 62: Combs, G. F., and E. H. Bossard, Further studies on available amino acid content of corn distillers dried grains with solubles. In Proceedings Distillers Feed Research Council Conference. pp Couch, J.R., A.A. Kurnick, R. L. Svacha and B. L. Reid, Corn distillers dried solubles in turkey feeds summary and new developments. In Proceedings Distillers Feed Research Council Conference. pp Cromwell, G. L., K. L. Herkelman, and T. S. Stahly, Physical, chemical, and nutritional characteristics of distillers dried grains with solubles for chicks and pigs. J. Anim. Sci. 71: Day, E. J., B. C. Dilworth, and J. McNaughton, Unidentified growth factor sources in poultry diets. In Proceedings Distillers Feed Research Council Conference. pp Grizzle, J.M., R. A. Voitle, and R. H. Harms, Evaluation of distillers dried grains with solubles in diets of turkey hens. Poultry Sci. 61: Hunt, J. H., J. J. Lyons, and J. M. Vandepopuliere, Corn stillage as a feedstuff for broilers and turkeys. J. Appl. Poultry Res. 6: Manley, J. M., R. A. Voitle, and R. H. Harms, The influence of distillers dried grains with solubles (DDGS) in the diet of turkey breeder hens. Poultry Sci. 57: Parsons, C.M., D. H. Baker, and J. M. Harter, Distillers dried grains with solubles as a protein source for the chick. Poultry Sci. 62: Potter, L. M., Studies with distillers feeds in turkey rations. In Proceedings Distillers Feed Research Council Conference. pp Waldroup, P. W., J. A. Owen, B. E. Ramsey, and D. L. Whelchel, The use of high levels of distillers dried grains plus solubles in broiler diets. Poultry Sci. 60:

123 Table 1. Ingredient Analyses for Turkey Feeding Trial. Meat & Bone Meal Corn, Ground yellow Soybean meal, 47% Distillers Grains Solubles Canola Meal Poultry Blend Nutrient (%) Total Digestible Total Digestible Total Digestible Total Digestible Total Digestible PROTEIN, CRUDE DRY MATTER FAT, CRUDE FIBER, CRUDE CALCIUM PHOSPHORUS, TOTAL POTASSIUM SODIUM CHLORIDE METHIONINE CYSTINE LYSINE ARGININE TRYPTOPHAN VALINE GLYCINE HISTIDINE PHENYLALANINE TYROSINE THREONINE LEUCINE ISOLEUCINE SERINE

124 Table 2. Selected Diet Composition 5-8 Wks of Age Control (C-S-MBM) DDGS Canola Canola & DDGS Ingredient (%) Trt 1 Trt 2 Trt 3 Trt 4 Corn SBM 47% Poultry blend (meat&bone) Distillers grains w/sol Canola meal Dicalcium phosphate Calcium carbonate Scarb Salt Potassium carbonate DL-Methionine L-Lysine Threonine MNVIT MNTM Choline Chloride 60% Choice White Grease Total Calculated Nutrient Content Crude Protein (%) Metabolizable Energy (kcal/kg) Crude fat (%) Calcium (%) Phosphorus, total (%) Phosphorus, Inorganic (%) Potassium (%) Sodium (%) Chloride (%) Digestible Total Digestible Total Digestible Total Digestible Total Met plus cys (%) Lysine (%) Arginine (%) Tryptophan (%) Valine (%) Glycine (%) Histidine (%) Phenylalanine (%) Tyrosine (%) Threonine (%) Leucine (%) Isoleucine (%) Serine (%)

125 Table 3. Selected Diets for Wks of Age Control (C-S-MBM) DDGS Canola Canola & DDGS Nutrient (%) Trt 1 Trt 2 Trt 3 Trt 4 Corn SBM 47% Poultry blend (meat&bone) Distillers grains w/solubles Canola meal Dicalcium phosphate Calcium carbonate Scarb Salt Potassium carbonate DL-Methionine L-Lysine Threonine MNVIT MNTM Choline Chloride 60% Choice White Grease Total Nutrient Crude Protein (%) Metabolizable Energy (kcal/kg) Crude fat (%) Calcium (%) Phosphorus, total (%) Phosphorus, inorganic (%) Potassium (%) Sodium (%) Chloride (%) Digestible Total Digestible Total Digestible Total Digestible Total Met + Cys (%) Lysine (%) Arginine (%) Tryptophan (%) Valine (%) Glycine (%) Histidine (%) Phenylalanine (%) Tyrosine (%) Threonine (%) Leucine (%) Isoleucine (%) Serine (%)

126 Table 4. Performance of Male Market Turkeys Feed Diet Body Weight Efficiency Number Description 11 wks 19 wks 5-19 wks lbs feed/gain 1 Control (Corn-Soybean-Animal Protein) As 1 + Distillers Dried Grains As 1 + Canola Meal As 1 + Distillers Dried Grains & Canola Meal As 4 + Tryptophan to Trt # As 5 + Isoleucine to Trt # As 6 + Arginine to Trt # Cool Environment Control (Corn-Soybean-Animal Protein) As 1 + Distillers Dried Grains As 1 + Canola Meal As 1 + Distillers Dried Grains & Canola Meal As 4 + Tryptophan to Trt # As 5 + Isoleucine to Trt # As 6 + Arginine to Trt # Warm Environment Control (Corn-Soybean-Animal Protein) As 1 + Distillers Dried Grains As 1 + Canola Meal As 1 + Distillers Dried Grains & Canola Meal As 4 + Tryptophan to Trt # As 5 + Isoleucine to Trt # As 6 + Arginine to Trt # Average P Value Diet NS NS Room Diet x Room NS NS NS Least Significant Difference (P<.05) Diet Room

127 Table 5. Carcass yield of market tom turkeys % of Diet Body Wt Carcass Number Description 19 wks Carcass Breast Breast lbs % Control (Corn-Soybean-Animal Protein) As 1 + Distillers Dried Grains As 1 + Canola Meal As 1 + Distillers Dried Grains & Canola Meal As 4 + Tryptophan to Trt # As 5 + Isoleucine to Trt # As 6 + Arginine to Trt # Cool Environment Control (Corn-Soybean-Animal Protein) As 1 + Distillers Dried Grains As 1 + Canola Meal As 1 + Distillers Dried Grains & Canola Meal As 4 + Tryptophan to Trt # As 5 + Isoleucine to Trt # As 6 + Arginine to Trt # Warm Environment Control (Corn-Soybean-Animal Protein) As 1 + Distillers Dried Grains As 1 + Canola Meal As 1 + Distillers Dried Grains & Canola Meal As 4 + Tryptophan to Trt # As 5 + Isoleucine to Trt # As 6 + Arginine to Trt # Average P Value Diet NS NS NS Room Diet x Room NS NS NS NS Least Significant Difference (P<.05) Diet Room

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129 Distiller s Grains: Focusing On Quality Control A tremendous amount of research has been conducted in a short period of time to determine the suitability of distillers dried grains plus solubles (DDGS) for poultry feeds By Nick Dale and Amy Batal, University of Georgia During the past several years, distiller s dried grains plus solubles (DDGS) has become a major feed ingredient in North America. Dozens of fermentation plants have been established in the mid-western United States where corn is fermented to produce alcohol to be mixed with petroleum. While it is sometimes debated whether this produces a net gain in fuel, there is no question that millions of tons of fermentation residues are now available to the feed industry. As might be expected, a tremendous amount of research has been conducted in a short period of time to determine the suitability of DDGS for poultry and animal feeds. Much of this research can be found at In studies conducted at the University of Georgia, it was found that broilers and laying hens can easily utilize 10% DDGS, although somewhat lower levels are recommended for the starter period. There are no inherent problems with DDGS, as might be the case with gossypol in cottonseed meal or trypsin inhibitors in underprocessed soy. Instead, any problems to be encountered with the use of DDGS are probably due to simple variations in quality. The process by which DDGS is produced is quite easy to understand. First, corn is ground and moistened, and an enzyme is added to convert starch to sugars. The material is then heated to eliminate unwanted microbes, and then a yeast is added to convert the sugars to alcohol. After fermentation, alcohol is removed by distillation and the remaining components are dried. As grain is composed of approximately 2/3 starch, which is consumed during fermentation, the process effectively triples the concentration of oil, fiber, and other minerals. The level of protein in DDGS is slightly more than triple that in the original corn, as the final product also contains yeast residues. Studies on DDGS at the University of Georgia found typical nutrient levels to approximate those in Table 1. Nutritionists and quality control specialists will need to focus on several additional areas to maximize the efficiency of DDGS use in their feeds. Variations in Proximate Composition For reasons which are not completely clear, the protein content of DDGS can vary from 24-29%. There can also be significant variations in fiber, while oil content generally is less variable. Thus, whenever receiving a new shipment of DDGS it is highly advisable to evaluate at least the crude protein content prior to incorporating the material into poultry feeds. Amino Acids Once crude protein has been determined, the area of amino acid availability is one which should be of prime concern to nutritionists. In general, we have found the availability of amino acids in DDGS to be extremely satisfactory, and only slightly lower than that of corn itself. Some decrease would be expected due to the effect of drying on the availability of amino acids such as lysine. Typical total and available amino acids in DDGS are presented in Table 2. What concerns most nutritionists, however, is the possibility of decreased amino acid availability in samples of darker color. This concern is completely understandable, as lysine availability is sharply reduced in overprocessed soybean meal. Fourteen samples of DDGS have been evaluated for total and available amino acids at this laboratory. In addition, we have attempted to relate the darkness of a sample to its amino acid availability. Our studies clearly indicate that dark DDGS samples have lower amino acid availability than lighter samples. In the photograph, three samples of DDGS are shown. Sample 1 is of light color, typical of that produced by many new DDGS plants. Sample 2 is intermediate, while Sample 3 is dark (all samples were taken from commercial shipments). In Table 2, the light sample (#1) is seen to have satisfactory levels of total and available amino acids. The intermediate sample (#2) had somewhat reduced levels of available amino acids, especially lysine, but this decrease was not severe. However, the dark sample (#3) had extremely low levels of both total lysine and lysine availability. This indicates that a significant amount of

130 the lysine had been destroyed during processing. In addition, we see that much of the lysine that was not destroyed had become biologically unavailable. Thus, the level of available lysine in sample #3 was only 1/3 that in the light colored sample (#1). As is the case with soybean meal, other amino acids were not as severely affected as lysine by the excessive heating. Metabolizable Energy Metabolizable energy (ME) has been determined on more than 25 samples of DDGS, using the TME n assay with Leghorn roosters. While samples with higher fiber content understandably have lower energy, a value of 2800 kcal/kg is appropriate for feed formulation. We have seen no indication that color of sample affects its ME. Available Phosphorus Many nutritionists have been surprised by the high level of available phosphorus in DDGS (see Table 1). As with other components, the level of total phosphorus is three times higher in DDGS than in corn. During the fermentation process, it is presumed that modest amounts of phytase are produced by yeast, thus converting phytin phosphorus to more available forms. We have found the phosphorus in DDGS to be approximately 65% available for poultry. Mycotoxins Just as levels of nutrients are tripled in DDGS as compared to the original grain, this also applies to concentration of mycotoxins, which are not destroyed by fermentation. However, while mycotoxins may occur, this is considered by the alcohol industry to be relatively unlikely. The profit from corn fermentation is clearly in the efficient production of alcohol. Corn which has been improperly stored and has developed aflatoxin or other mycotoxins may not give the same efficiency of alcohol production as higher quality corn. Thus, while the possibility of mycotoxin contamination of DDGS cannot be ruled out, at present toxin contamination is not considered likely. -- Egg Industry, April 2005 Nick Dale and Amy Batal, Poultry Science Department, The University of Georgia Athens, GA Tel:(706) TABLE 1. Nutritional profile of distillers grains plus solubles (90% DM) Protein (%) 27.0 Oil (%) 9.5 Crude fiber (%) 9.0 Calcium (%) 0.33 Phosphorus, total (%) 0.75 Phosphorus, available (%) 0.49 Sodium (%) * Metabolizable energy (kcal/kg) 2810 *Significant variation seen between suppliers.

131 TABLE 2. Amino acid composition and availability of several distillers grains plus solubles samples differing in color (90% DM) Light (#1) Intermediate (#2) Dark (#3) Total A.A. Availability Total A.A. Availability Total A.A. Availability (%) (%) (%) (%) (%) (%) Lysine Methionine Cystine Threonine Tryptophan Arginine Isoleucine Valine Leucine