MAINTAINING CONJUGATED LINOLEIC ACIDS (CLA S) IN PASTURE-FED BEEF

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1 MAINTAINING CONJUGATED LINOLEIC ACIDS (CLA S) IN PASTURE-FED BEEF Prepared by: Dr. Shanon Scott CLA fat Good fat Bad fat Omega-3 fat Saturated fat Polyunsaturated fat Trans fat Unsaturated fat Monounsaturated fat

Types of fats and oils High omega-3 PUFA High omega-6 PUFA High MUFA High SFA Saturated Fats Saturated fats are found in animal products such as butter cheese, whole milk, ice cream, cream, and fatty

2 Types of fats and oils High omega-3 PUFA High omega-6 PUFA High MUFA High SFA Saturated Fats Saturated fats are found in animal products such as butter cheese, whole milk, ice cream, cream, and fatty meats, and oils such as coconut, palm, and palm kernel oil. Monounsaturated Fats Found in Olive oil, canola oil, peanut oil, avocados. Omega-6 Fatty Acids Found in Vegetable oils like sunflower, corn, and safflower oils, as well as meat from grain-fed livestock. Omega-3 Fatty Acids Omega-3 fatty acids are found in oily fish like salmon and flaxseed and canola oils and grass-fed beef.

cancer) Reduce likelihood of depression, schizophrenia, attention deficit disorder (hyperactivity), or Alzheimer s disease What is the link between pasture and omega-3 fatty

3 What are the health benefits of omega-3 fatty acids? Reduce likelihood of high blood pressure or heart attack Help prevent and manage chronic conditions (type 2 diabetes, kidney disease, rheumatoid arthritis, certain types of cancer) Reduce likelihood of depression, schizophrenia, attention deficit disorder (hyperactivity), or Alzheimer s disease What is the link between pasture and omega-3 fatty acids? Impact of omega-6 to omega-3 ratio A high ratio has been linked with an increased risk of cancer, cardiovascular disease, allergies, depression, obesity and auto-immune disorders (Simopoulos and Robinson, 1999) 12.5 to to 1 Trans Fats G.J. Miller, J. of Food Quality, 9:

4 Trans-fatty acids are found in fried foods, commercial baked goods, processed foods and margarine. What are the health risks of man-made trans fat? Raises bad cholesterol levels Lowers good cholesterol Increases risk for heart disease Linked to memory problems Not all trans fats are equal! Man-made trans fats Conjugated linoleic acids Conjugated linoleic acids (CLA s) Found in animal products, especially from ruminants - Beef - Lamb - Milk (not skim) - Cheese - Butter - Turkey What are the health benefits of conjugated linoleic acids (CLA s)? Anti-cancer properties found for beef extracts (Pariza et al. 1979; 1985) CLA found in milk fat inhibited cancer cell growth (Parodi 1997) Enhanced immune function (Albers et al. 2003) Reduced body fat mass (Blankson et al. 2000) Decreased blood cholesterol (Nicolosi et al. 1997) What s the link between pasture and CLA? Increased grass in diet increases CLA compared with silage (French et al. 2000) 1.2 CLA (% fatty acids) Silage % Grass in diet What s the link between pasture and CLA? Pasture finishing enhances levels of conjugated linoleic acids (CLA) in beef lipids compared with grain.

5 However, pasture finishing can impact grade. Research trial of diet and time on feed on CLA levels in beef. on the effect Objectives Develop a feeding regime to maintain the positive nutritional attributes of pasturefed beef while improving meat grade Investigate effects of adding sunflower seeds, a good source of PUFA (Mir et al. 2000), or carnitine, a vitamin-like compound shown to increase fat deposition and marbling in cattle (Greenwood et al. 2001), to finishing diets of pasture-fed cattle on lipid fatty acid profiles Methods 64 steers grazed 11 paddocks (94.4% grass, 4.6% alfalfa) 13 May to 02 Sep steers (503.1 ± 34.9 kg) slaughtered off pasture (Time 0) and carcass data and ribeye steaks obtained Remaining 48 steers (469.3 ± 34.5 kg) fed a basal diet of 80% barley grain and 20% hay Allocated to 4 diets: - 0 or 14% of DM whole black oil sunflower seeds (SFS) - 0 or 200 mg added carnitine (Carnipass, Lonza, Inc., USA) per kg DM Blood sampled every 14 d for analysis of plasma carnitine Feed intake measured every 7 d; feed sampled for nutrient, fatty acid and carnitine analysis Steers weighed every 14 d to calculate gain 16 steers slaughtered every 28 d (Times 1, 2 & 3) at 500 kg BW and 4 mm backfat Carcass data and ribeye steaks obtained One steak per animal analysed for meat quality One steak per animal trimmed of fat and lean muscle analysed for moisture, crude fat and protein Lipid extracted and analysed for fatty acids Experimental diets - composition +SFS +CAR +SFS -CAR -SFS +CAR -SFS -CAR Dry matter (%) Protein (% DM) Crude fat (% DM) OM digestibility (%) Ash (% DM) NDF (% DM)

Experimental diets fatty acids +SFS +SFS -SFS -SFS Fatty acids (mg/100 mg fat) +CAR -CAR +CAR -CAR Palmitic (16:0) 8.25 7.94 19.27 18.75 Palmitoleic (16:1 n7) 0.08 0.07 0.20 0.18 Stearic (18:0) 4.

6 Experimental diets fatty acids +SFS +SFS -SFS -SFS Fatty acids (mg/100 mg fat) +CAR -CAR +CAR -CAR Palmitic (16:0) Palmitoleic (16:1 n7) Stearic (18:0) Oleic (18:1 n9) cis Linoleic (18:2 n6) cis α-linolenic (18:3 n3) γ-linolenic (18:3 n6) Effect of diet on dry matter intake (DMI) and average daily gain (ADG) kg/day a a b b +SFS+CAR +SFS-CAR -SFS+CAR -SFS-CAR ADG DMI

Conclusions Addition of carnitine to finishing diets of pasture fed steers did not affect animal performance, carcass quality or meat fatty acid

11 Conclusions Addition of carnitine to finishing diets of pasture fed steers did not affect animal performance, carcass quality or meat fatty acid prodiles Addition of SFS to finishing diets of pasture fed steers increased DMI and doubled levels of cis-9, trans-11 CLA with diets without SFS

12 WINTER SITE MANAGEMENT BENEFICIAL MANAGEMENT PRACTICES FOR NUTRIENT MANAGEMENT OF YOUR LIVESTOCK WINTERING SITE Prepared by: Dale Timmerman Dale Timmerman s presentation is based on the following Factsheets.

20 FORAGE SPECIES SELECTION Prepared by: Jane Thornton INTRODUCTION High yield and longevity begins with choosing the correct forage. The main points to consider are soils, climate and forage use. Take the time to understand and choose forages adapted to their intended use and environment so that you can benefit from high yields and longevity. It is important thing to realize that not all land will be able to support every type of forage or activity that you desire. You may need to make compromises on what you seed or what or how you use a piece of land. WHAT IS AVAILABLE? In Manitoba there are about 36 genera and species to choose from, that includes tame and natives. If you count the number of different cultivars then the number increases substantially, but there is less difference between cultivars than there is between genera and species so your main search should concentrate on picking the correct genera/species and consider cultivar secondly. Despite the high number of choices most forage stands will be made up of one or more of seven main species. Many of the other species are developed for specialized uses such as spring grazing, or adaptation such as salt tolerance. ADAPTATION Start by considering your soils. If the land is new to you the Canada Land Inventory and limitation ratings will be helpful. If you have been farming the land for some time you may already be aware of some of the soil properties. Forages all have different adaptation or tolerance to things like internal soil drainage, ph, salinity, water table, texture, fertility etc. and should be picked accordingly. While many forages have wide adaptation like alfalfa and the brome grasses, some have been developed or introduced to Canada because they fit in specific situations like tall wheatgrass for saline areas, or reed canary grass for areas prone to flooding. Secondly, consider your climate and this includes rainfall, temperature, length of growing season, and winter conditions. Many sources will give you a precipitation range that the forage will do best at. Remember that Manitoba is a continental climate and that means one of extremes. Many good cultivars have been developed or selected and tested by Ag Canada over the decades and sticking to one of these may be your best bet. I am often asked about cultivars that are from the states or other parts of Canada. They might be great, or they might be terrible. The bottom line is that as forage specialist I may not have any information on the variety and so have no way of knowing how well

21 adapted the forage is to our MB conditions. If you choose to try one of these varieties, go with a small acreage to start with. USES Forages are generally adapted to two uses: pasture or hay. Hay types have a growth form that is more conducive to haying operations. They develop tall stems with the leaves arranged on the stems. This allows for maximum yields for hay as you cut and remove the bulk of the material. On the down side you also remove the growing point so the hay types generally do not have good re-growth capabilities. Smooth Brome is a good example of a hay type. Pasture types have a growth form that keeps the growing point close to the ground and the leaves all come from the crown of the plant. Since you do not remove the growing point with each grazing they re-grow quickly. The down side when used for hay is that you lose some yield because the leaves are near the ground and will be below the cutting height. Orchard Grass and Meadow Brome are good examples of pasture types. ANIMAL PREFERENCE Not all forages are equally liked by animals so there is a balancing act when choosing forages. If you have a situation that requires a specially adapted forage, such as, tall wheatgrass for saline areas for example, then you need to be aware that this forage is coarse and not very palatable. Livestock will only graze this forage when it is young. If you choose to make a complex mix of forages then you need to be aware that your animal may select against certain species. Do your homework and select forages that are adapted and work well together. It is important to know that animal preference is not necessarily linked to forage quality. Many forages that would be second choice, if the animal was given a choice, may be of equal feed value. SEEDING MIX: COMPLEX, SIMPLE OR MONOCULTURES? There is no right or wrong here. It seems to come down to personal preference and management style but when starting fresh you might want to consider the following: A Case for Monocultures Monocultures are ideal in very specific situations such as land that floods in spring. Choosing one adapted species will produce the most and live the longest. Monocultures are often seeded to target specific markets, such as export timothy or alfalfa dairy hay. Herbicide selection is less complicated when one species is planted and may allow clean-up of specific weed problems. A Case for Mixtures

22 The simple mix: One grass and one legume is a standard type of mix. Grasses are well adapted to the prairies and non-bloating. The inclusion of a legume, generally alfalfa, will provide nitrogen to the system and increase forage quality through the season. The two species mixed together complement each other by using different resources and having different growth forms. Simple mixes are easier managed in grazing systems because the animal will not have the chance to be as selective. The complex mix: Complex mixtures are often used when the soils or topography is highly variable. Each forage will survive and do best in its specific niche ensuring that the land is covered by adapted and usable forage. Complex mixtures can provide forage over a long growing season as each species will have a slightly different growing period. Complex mixtures may work best in Management Intensive Grazing systems as this system controls livestock forage selection and provides adequate rest periods for the various forages. Under Extensive Grazing Systems the animal will select favored forage species and under utilize other species entirely. This sets up a scenario of overgrazed species and species used very little or not at all. Simple or complex mixtures will change over time as a result of individual forage longevity, environment and/or management. SEED QUALITY It is tempting to buy inexpensive seed but it really does come at a cost. Lower grade seed has more weeds, and poor germination rates and seedling vigour. It is crucial that forage stands get a good start as this will affect stand productivity over the life of the stand. Buy the best quality seed you can afford. Forage Adaptation and Characteristics Alfalfa Medium-lived perennial Adapted to a wide range of climatic and soil conditions Relatively drought, salt and alkaline tolerant Not tolerant to acidic soils - anything below a ph 6.0 Intolerant to flooding or poor internal Sainfoin Claim to fame - non-bloating Does best on deep well drained soils that have good moisture holding capacity (much the same as alfalfa) but also so success on line gravelly soils Does not tolerate salinity, wet soils or high water table Soil ph near neutral and high in lime

23 drainage Claim to fame - high yielding and nutrient status Better than 300 mm precipitation May persist under dry conditions but will be low yielding Seed at 13 to 20 kg/ha Not competitive with aggressive grasses, some success with bunch grasses such as CWG or Russian wildrye Alsike Clover Short lived perennial Dominates stands for the first few years and then dies out Withstands spring flooding to 6 weeks It is intolerant of drought and high temperatures Intolerant of shading so best with shorter grasses and in pasture situations Poor salinity tolerance Suited to acidic soils and more tolerant to alkalinity than most clovers Needs minimal land preparation but must be shallowly seeded Birdsfoot Trefoil Adapted to unfertile soils with poor internal drainage - useful on some organic soils Withstands several weeks of flooding Withstands high alkalinity and some salinity It does not do well with other plants due to shading and competition. It is best planted alone or with non aggressive grasses Withstands grazing better than most legumes but attention to fall utilization is similar to alfalfa Smooth Brome Likes moist well drained soils Fairly tolerant to alkalinity and somewhat tolerant to salinity and acidity Will survive some drought and high temperatures by going dormant Will tolerate about 2 weeks of flooding prior to the start of spring growth Stands can become sod bound due to its vigorous rhizomes which also make it difficult to eradicate Best suited for hay production Has poor regrowth capabilities with slow growth after the spring and early summer Meadow Brome Adapted to the same soils and climate as smooth brome Slower to establish than smooth brome Sensitive to spring flooding Early spring growth Start grazing when plants are cm high, remove livestock when 8-10 cm, give 3 to 4 weeks rest and leave about 15 cm stubble at the end of the grazing season Claim to fame - excellent regrowth characteristics Orchard grass Best adapted to areas with 500 mm of precipitation per year and well drained soils Somewhat tolerant of acidity Very shade tolerant Somewhat drought tolerant - less than smooth brome but more than timothy - prolonged drought will kill it and sandy Timothy Adapted to cool moister areas Very tolerant to acidity Does well on water logged soils, low lying peaty areas Can grow on clay, silt and sandy soils with adequate moisture Good stand establishment and productivity Low tolerance to drought

24 soils are generally too dry for good production Not very tolerant of salt or alkalinity Start grazing when cm and remove when down to 10 cm Main food storage is in the lower stem and leaf bases, therefore it does not tolerate close and continuous grazing Excellent regrowth during the hot summer months and into the fall Claim to fame - rapid regrowth and very palatable Tall Fescue Deep rooted, long-lived and hardy Wide range of adaptation - grows best under relatively cool conditions One of best grasses for poorly drained soils Tolerates alkalinity, acidity, and salinity Fairly drought resistant and grows well on dry soils Forms heavy turf which makes it good for waterways, eroding gulleys and areas with heavy traffic Good production throughout the season Most palatable when leaves are young or after killing frost Claim to fame good nutrient quality as stockpiled forage Intermediate Wheatgrass Short-lived, sod forming Best on well drained fertile soils Requires at least 375 mm precipitation per year for good production Good alkalinity tolerance Does not tolerate salinity, wet conditions or poor drainage Good production when grown with a legume Provides good fall pasture if moisture is favorable Slender Wheatgrass Short-lived native perennial Quick to establish and good production for 3 to 4 years Adapted to a wide range of soils but prefers sandy loams Tolerates alkalinity Saline tolerant Not tolerant of salinity or alkalinity Cutting or grazing before the heads emerge greatly weakens the plant and reduces productivity Easily weakened if heavily grazed Reed Canary Grass Long lived Flood tolerant for up to 2 months Thrives on land with a high water table Intolerant to salinity Starts growth early and has a good growth pattern throughout the season High yielding Good quality if used before seed head emergence Graze when 30 cm high and remove when 10 cm Low palatability is an issue if in a mixture, best planted alone or fenced separately to prevent cattle selecting against it Tall Wheatgrass Does well on saline soils where foxtail barley usually dominates Moderate alkalinity tolerance Can withstand 5 weeks of spring flooding Prefers 375 mm precipitation per year Poor drought tolerance Winter hardy Poor germination and slow to establish Not as palatable as other wheatgrasses but can be fenced separately to encourage use Crested Wheatgrass Long-lived bunch-type grass Very winter hardy Deep rooted and drought resistant Early spring growth from April to late June Does well on most good soils but also has the ability to establish on sandy soils Poor quality once it goes to seed

25 Is not tolerant to close grazing Cures quite well on the stem and can be saved for late season grazing Needs about 350 mm precipitation per year Claim to fame - early spring growth and resistant to grazing Russian Wild-rye Long-lived perennial bunch grass Does not tolerate spring flooding Prefers fertile loams but can be established on sandier soils in dry regions Generally can be grown wherever Crested wheatgrass can be grown Begins growth early in the year Claim to fame - good palatability and nutritive status into late fall Western Wheatgrass Long-lived sod forming grass Adapted to a wide range of soils but prefers heavy and somewhat alkaline soils with good drainage Can tolerate some flooding and drought Slow to establish but once it gets going it spreads quickly through an extensive rhizome system Starts growth in early spring and continues until fall Does not tolerate continuous heavy grazing Green Needlegrass Prefers moist heavy clays and fertile soils. Will grow on sandier soils with an underlying water table Most palatable of the needle grasses Good spring protein levels - 20% and adequate fall levels - 8% Not tolerant to overgrazing Big Bluestem Long-lived native warm season grass Flowers well into summer Good palatability and nutritive value before maturity Claim to fame good quality after cool season forages have declined in quality

Feeding Oilseeds To Beef Cattle

Feeding Oilseeds To Beef Cattle J. McKinnon*, H. Block*, V. Racz* & S. Scott** Department of Animal & Poultry Science Saskatoon, Saskatchewan University of Saskatchewan, Saskatoon, Sk. Agriculture & Agri-Food