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1 Nutrition & Helth: Beef O By G.C. DUFF nd J.D. ALLEN Duff is deprtment hed nd professor t Montn Stte University, nd Allen is recent doctorl grdute of The University of Arizon. One dunting tsk for writing out dietry nutrient llownces for eef cttle is relted to the vst numer of production systems used. Beef production vries widely from grzing systems utilizing ntive pstures or improved pstures to confinement feeding utilizing high-concentrte diets. Therefore, this rticle will present rod overview of eef cttle nutrition sed on scientific literture nd on Ntionl Reserch Council (NRC) 1996 recommendtions. Digestive physiology There re severl unique spects of the digestive trct of eef cttle tht deserve ttention. Strting t the hed, in the mouth, eef cttle hve no upper incisors. When grzing, eef cttle will wrp their tongue round forge nd with the muscles in the ck of their hed, use the ottom incisors to sher off the plnt prticles. Another importnt spect is the copious quntity of sliv tht eef cttle produce. Besides iding in moistening the feed olus for swllowing nd iding in tste, sliv is source of 1. Nutrient requirements for growing nd finishing eef cttle,,c Bodyweight, l Mintennce requirement per dy---- NEm, Mcl Metolizle protein, g Clcium, g Phosphorus, g Averge dily gin, l Net energy for gin, Mcl per dy Metolizle protein required for gin, l. per dy Clcium required for gin, g per dy Phosphorus required for gin, g per dy Adpted from 7th rev. ed., Nutrient Requirements of Beef Cttle, 1996, Ntionl Reserch Council. Crystlline vitmin A should e dded t level of 1,100 IU/l. DM. c Weight of niml t smll mrling, 1,172 l.; ADG rnge, 1.1 to 5.5 l. per dy; reed, Angus. 30 Feedstuffs, Septemer 14, 2011 recycled nutrients for ruminnts, prticulrly nitrogen (ure) nd minerls (e.g., phosphorus, mgnesium, sodium, potssium nd chloride). Sliv is lso importnt in uffering the rumen. The mount of sliv produced cn e s much s 180 liters per dy nd is dependent on the diet consumed. The esophgus is hollow tue tht llows the olus to e trnsported to the next section of the gstrointestinl trct (GIT). Peristltic ctions in the esophgus re importnt to llow ruminnts to regurgitte the feed olus, remsticte nd reswllow undigested mteril (rumintion). The time spent ruminting is dependent on diet with grzing cttle ruminting more thn cttle consuming high-grin diets typicl in feedlot settings. It hs een estimted tht eef cttle cn ruminte up to 8 hours per dy. In ddition to regurgittion of undigested feedstuffs, the esophgus is importnt in eructtion of gses produced during fermenttion in the rumen. When eructtion is impired nd/or disrupted, lot cn occur, which, if gone undetected, cn result in deth. Two types of lot cn occur in ruminnts. One type is free-gs lot, which occurs secondry to fctors tht prevent eructtion. The second type of lot is frothy, where froth produced y fermenttion prevents eructtion of gses. Feeding the ionophore monensin hs een shown to reduce lot on whet psture nd my e effective in reducing feedlot lot either y reducing gs production or y ltering the feeding ptterns of the cttle. The reticulum (honeycom) is the next section of the GIT, nd this section is responsile for regulting digest flow into nd out of the rumen. It is in this section where shrp ojects (e.g., nils nd wires) tht my e consumed y the nimls cn ccumulte nd, over time, penetrte the reticulum lining, llowing rumen contents to lek into the peritonel cvity cusing hrdwre disese. Diry producers often plce mgnet in the rumen to ttrct the ojects. The rumen of the niml is virtully fermenttion vt. Ruminl fluid contins nywhere from 30 illion to 50 illion microorgnisms (cteri nd protozo) per milliliter of ruminl fluid. Just like rumintion, the microil popultion present in the rumen is relted to diet consumed. The vrious types of cteri present is eyond the scope of the rticle, ut with forge diets, the primry cteril species will e cellulolytic nd hemicellulolytic, wheres with grin-sed diets, mylolytic cteri will e in greter concentrtions. In ddition, proteolytic nd lipolytic cteri re present in the rumen nd re responsile for digesting protein nd lipids, respectively. The omsum (mny folds) is responsile for regulting flow to the omsum nd is site of wter sorption. The next section of the eef cttle digestive trct is the true stomch, referred to s the omsum. It is similr in function to the stomch of monogstric nimls such s the pig. The lower digestive trct is virtully identicl to other species; however, the duodenum is unique in tht it secretes greter quntities of nucleses nd less pncretic mylse thn other species of nimls. The greter mounts of nucleses is relted to rekdown of cteril protein nd less mylses is relted to decresed mounts of strch entering the smll intestine versus other species. The lrge intestine in eef cttle is proportionlly lrger thn omnivorous species nd proportionlly smller thn non-ruminnt herivores such s horses nd rits. With high-concentrte diets, fier digestion my e shifted to the lrge intestine due to decresed fier digestion in the rumen s result of decresed ruminl ph. However, it is not known whether the lrge intestine cn fully compenste for the incresed fier lod. Ruminl development During the first few months of ge, clf is ntomiclly ruminnt ut functionlly monogstric. Antomiclly, suckling

2 clf hs the ility to ypss the reticulorumen nd dump milk directly into the omsum for digestion vi the esophgel groove. This is prticulrly helpful ecuse clf is not orn with microil popultion in its forestomch nd must rely on its own digestive enzymes (secreted in the omsum nd intestine) for milk digestion. Eventully, s the clf commingles with other nimls nd egins to consume feedstuffs, the rumen ecomes inoculted with the microes needed for fermenttion nd voltile ftty cid (VFA) production. VFAs re prticulrly importnt in developing the rumen wll (incresing rumen surfce re), which in turn improves mximl VFA sorption; lthough hy cn stimulte rumen development, strter diets high in cerel grins (> 50% s fed) hve proven more effective for rumen wll development in Holstein clves. provided with n dequte source of wter. If feed intke diminishes drsticlly for no pprent reson, the first thing producers should check is the wter source. Another fctor tht will ffect wter requirements is environmentl temperture. Crohydrtes Crohydrtes re importnt for ll spects of eef cttle nutrition. For grzing ruminnts, forges comprise the mjority of the diet. Depending on loction, for cttle grzing ntive rnges, forges consumed include fors, shrus nd grsses, wheres cttle in other regions of the country will rely hevily on introduced forges including rome grss, Ruminl fermenttion The first step in ruminl fermenttion occurs in the mouth with the nimls reducing the plnt prticle size with the molrs. In ddition, rumintion is responsile for further reduction in prticle size. These ctions serve to increse the surfce re of plnt prticle which llow cteri to ttch to plnt prticle. A symiotic reltionship exists etween the host niml nd the cteril species. The host niml supplies wrm, moist environment with sustrtes introduced nd removl of end products of ruminl fermenttion. This llows the microes to rek down the firous mteril nd produce end products tht the niml cn utilize. The microes will ferment the crohydrte portion of plnts nd produce VFAs. In ddition, gses re produced including cron dioxide nd methne. The nimls cn utilize VFAs for energy with n estimted 70-80% of the cloric requirements met y VFAs. In ddition, other components re fermented in the rumen resulting in production of microil protein nd B vitmins. COSTS $28 MAKES YOU $58 THAT S ZILMANOMICS Feed Zilmx for the lst 20 dys for n dditionl 33 ls. of hot crcss weight nd n extr $58 per hed, gross profit. 1 Tht s every four weeks. Let s see the folks on Wll Street et those returns. Contct your Zilmnomics dvisor tody. Beef you cn count on. Arturo DiModic 1998 Nutrients Although eef cttle require the sme nutrients s other species of nimls, dietry concentrtions my differ ecuse of the unique ility of ruminnts to ferment dietry components. Wter Without dout, wter is primry nutrient for ll species. Beef cttle should e Merck Animl Helth Copyright 2011 Intervet Inc., susidiry of Merck & Co., Inc. All rights reserved. BV-Zil R1-FS 1 33 ls. hot crcss weight in steers sed on verge outcome of feedlot reserch trils. $58 per hed gross profit ($30 net, fter product cost) sed on historicl verges. Not for use in nimls intended for reeding. Do not llow horses or other equines ccess to feed contining zilpterol. Do not use in vel clves. 3 dy withdrwl period. For complete informtion refer to product lel. Septemer 14, 2011, Feedstuffs 31

3 timothy, ryegrss, etc. For finishing eef cttle, crohydrtes re mjor portion of the diet. The microil popultion produces the cellulses nd hemicellulses to rek down the structurl crohydrtes in the plnts. Strches nd sugrs re lso extensively fermented y microil popultion in the rumen. The primry VFAs produced re cette, propionte nd utyrte. Acette is produced in the highest proportions, followed y propionte nd utyrte. Adding cerel grins will increse the mount of propionte produced, leit cette will still e in the gretest proportion. Protein Bcteril protein synthesis my ccount for s much s 50% of the protein nd mino cids needed y cttle. Beef cttle cn metolize dietry protein, s well s non-protein nitrogen sources such s ure. Ruminnts hve the ility to upregulte low-qulity protein. Ruminnts cn tke nitrogen source such s ure nd turn it into moderte-qulity cteril protein. Furthermore, it is generlly recognized tht ruminnts down-regulte high-qulity protein sources. Down-regultion would e tking high-qulity protein nd turning it into moderte-qulity cteril protein. With the 1996 NRC, protein requirements for eef cttle were sed on metolizle protein rther thn formulting on crude protein requirements s with previous pulictions. This method divides protein requirements into niml nd microil components. Significnt progress ws mde in evluting protein requirements with the 1996 NRC puliction; however, complete implementtion of the puliction hs not een ccomplished. It is generlly recognized tht the metolizle protein system etter descries requirements of eef cttle; however, 2. Nutrient requirements for growing ulls,,c Bodyweight, l ,100 1,320 1,540 1, Mintennce requirement per dy----- NEm, Mcl Metolizle protein, g Clcium, g Phosphorus, g Averge dily gin, l Net energy for gin, Mcl per dy Metolizle protein required for gin, l. per dy Clcium required for gin, g per dy Phosphorus required for gin, g per dy Adpted from 7th rev. ed., Nutrient Requirements of Beef Cttle, 1996, Ntionl Reserch Council. Crystlline vitmin A should e dded t level of 1,100 IU/l. DM. c Weight t mturity, 1,958 l.; ADG rnge, l. per dy; reed, Angus. 32 Feedstuffs, Septemer 14, 2011 formultion on totl crude protein continues to e prcticed. Crude protein concentrtions used y consulting feedlot nutritionists rnges from 12.5% to 14.0% (men 13.34%; mode 13.5%) with ure concentrtions in the finishing diet of 0-2.0% (men 1.01%; mode 1.2%; Vsconcelos nd Glyen, 2007; J. Anim Sci. 85: ). In ddition, only 9 (31.03%) out of 20 (68.97%) nutritionists responding to the questionnire reported formulting sed on degrdle intke protein (DIP). Energy Although not nutrient per se, it is importnt to discuss energy requirement of eef cttle. Energy is term used to define the cpcity to do work. In the U.S., the clorie, kiloclorie (kcl) nd meg clories (mcl) re the common terms used in nutrition. Gross energy (GE) is the mount of het produced when feedstuff is completely oxidized using om clorimeter. Digestile energy (DE) is otined y sutrcting fecl energy from GE consumed nd is the mount of energy pprently sored from feed. Metolizle energy (ME) is determined y sutrcting urinry nd comustile gs loss from DE. Net energy (NE) is determined y sutrcting energy losses from rumen fermenttion nd tissue metolism from ME. Net energy will predict the mount of energy ville for mintennce nd production. The mintennce energy requirements of eef cttle hve een well estlished s 77 kcl/w 0.75 where weight (W) is odyweight in kilogrms. Energy is considered first when lncing for eef cttle. Beef cttle will otin mjority of their energy requirements from fermenttion of crohydrtes. Lipids nd proteins cn lso supply energy to cttle. As mentioned previously, 70-80% of the niml s cloric requirements will e met y VFAs. Minerls Vitmin nd minerl requirements for eef cttle remins unchnged from previous versions of this rticle. When formulting for newly received eef clves, trce minerl concentrtions should e incresed to ccount for decresed feed intke during the first few weeks fter rrivl. Tle 6 hs een included s reference to compre formultions from consulting nutritionists vs. NRC recommendtions. It ppers tht most mcro nd micro minerls re formulted slightly higher thn NRC recommendtions. Vsconcelos nd Glyen (2007) suggested tht over supplying nutrients my reflect the nutritionist s desire to err on the side of cution. The totl minerl or sh content of the niml ody represents very smll percentge of the totl dry mtter content. One uthor hs expressed ovine on ft-free sis, minus the contents of the gstrointestinl trct s pproximtely 73% wter, nerly 22% protein nd 5.3% sh, plus smll mounts of crohydrtes. Reserchers t the University of Missouri nlyzed the odies of severl red nimls nd found minerl vlues of 1.3% clcium, 0.74% phosphorus, 0.16% sodium, 0.19% potssium, 0.11% chloride, 0.04% mgnesium nd 0.15% sulfur. Nturlly, there ws whole host of other minerl elements in very minute quntities. The 1996 NRC ulletin sttes tht there re 17 minerl elements required y eef cttle. However, ecuse of the nture of the diets of most eef nimls, it is rre tht more thn of such minerl elements re deficient. A rief discussion of those minerl elements tht might e expected to e deficient in typicl diets of cttle will follow. Clcium. Severl dietry ingredients supply ner optiml levels of clcium, including the fmily of legume forges, plus severl other types of forges especilly young, fst-growing plnts. The cerel grins re quite low in clcium. Thus, forging cttle might e expected to otin nerly dequte clcium from their grzing, wheres feedlot cttle on very high-energy diets cn e expected to otin insufficient clcium from their diets. Clcium cn e supplied so economiclly from ground

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5 3. Nutrient requirements for pregnnt replcement heifers,,c Months since conception NEm, Mcl per dy Mintennce Growth Pregnncy Totl Metolizle protein, g per dy Mintennce Growth Pregnncy Totl Clcium requirement, g per dy Mintennce Growth Pregnncy Totl Phosphorus requirement, g per dy Mintennce Growth Pregnncy Totl Averge dily gin, l. per dy Growth Pregnncy Totl Bodyweight, l. Shrunk ody Grvid uterus mss Totl ,010 1,078 Adpted from 7th rev. ed., Nutrient Requirements of Beef Cttle, 1996, Ntionl Reserch Council. Crystlline vitmin A should e dded t level of 1,100 IU/l. DM. c Mture weight, 1,172 l.; clf irth weight, 88 l.; ge t reeding, 15 months; reed, Angus. limestone tht there is no reson for clcium deficiency except lck of ttention to the cttle-feeding enterprise. Phosphorus. Most grins re pretty good source of phosphorus (0.25+%), with legume hys somewht less (0.20%) nd grss hys t 0.20%. Supplementl feed-grde phosphorus is more expensive thn sources of clcium. However, it is foolish to limit the intke of phosphorus elow tht recommended y NRC, ecuse such prctice cn decrese rte of gin, even though ll the other nutrient requirements hve een met. Supplementl phosphorus s well s supplementl clcium cn e supplied y either diclcium phosphte or stemed one mel. Nturlly, there re mny other sources of dietry phosphorus, including phosphoric cid (utilized in liquid-supplements production) nd defluorinted rock phosphte. It should e pointed out tht there is no known enefit in feeding levels of phosphorus greter thn those recommended y NRC. Furthermore, it is criticl tht phosphorus is not supplied to eef cttle in excessive quntities ecuse unused phosphorus will interfere with clcium sorption nd e excreted from the ody, which my eventully find its wy to surfce wter, thus hving environmentl implictions. Slt. Mny people provide slt in totl mixed rtion, wheres others my feed it on n d liitum sis, lone or mixed with sources of clcium nd phosphorus. Often, slt, s trce-minerlized slt, is utilized s crrier for most of the so-clled trce minerls. Becuse the feeding of selenium is controlled y the Food & Drug Administrtion, it would not fit too well into free-choice slt sitution. There is no enefit to overfeeding slt. Furthermore, ecuse of the ese of feeding slt, nd ecuse slt is not expensive, there is no cuse for slt deficiency except poor mngement. Potssium. Legumes re exceptionlly good sources of potssium (lflf hy contins 1.5%); corn silge contins pots- 34 Feedstuffs, Septemer 14, 2011 sium t out the requirement for cttle (0.8%), nd the cerel grins re deficient in potssium (0.3%). Therefore, cttle fed on very high-grin diets should hve their totl dietry potssium checked, proly requiring considerle supplementtion. Optiml potssium level is relted directly to optiml rtes of gin so it is expensive to not feed dequte potssium. Iodine. Supplementl iodine is needed y reproducing cttle, ut there is little rtionle to feeding iodine to growing nd finishing cttle. A possile exception to this is tht iodine compounds re utilized in lleviting the symptoms of footrot. Selenium. In eef cttle, the supplementtion of diets with selenium is restricted lrgely to reproducing nimls, since the use of supplementl selenium for growing nd finishing cttle, lrgely, hs not shown positive response. As indicted ove, the ddition of selenium to eef cttle diets is under the control of FDA nd so is hndled y feed mnufcturers who hve een given permission to mke such dditions. However, new spect of selenium supplementtion hs risen. It hs een demonstrted tht lctting cttle given supplementl selenium in the form of selenium-yest compound utilized selenium more efficiently thn those whose supplementl selenium ws in either the selenite or selente form. Since the rnge etween optiml nd toxic levels of selenium is nrrow, possily less of the selenium yest source would e required. Colt nd copper. In certin res of the U.S., especilly prts of Florid nd Michign, the soil is so deficient in colt nd copper tht crops grown on such soils reflect the deficiencies. Both of these elements re identified with the production of red lood, nd deficiency of either will e reflected in nemic conditions. Both re supplied redily in mnufctured feed nd in trce-minerlized slt. Mgnesium. Grss tetny is the nme given to mldy tht seems to occur most often in cttle grzing lush psture in erly spring when the wether is especilly cool. However, there hve een reported clinicl oservtions under other conditions. The feeding of 1-2 oz. of mgnesium oxide per hed, dily, seems to prevent grss tetny. However, mgnesium oxide ppers to not e pltle to cttle, so methods of msking its flvor, such s mixing it with pound or two of corn, my e helpful. Mgnesium cn e suspended in free-choice liquid supplements, nd grzing cttle seem to consume sufficient mounts of the mixture to prevent grss tetny. Vitmins Cttle out-of-doors, consuming green grss, were thought to e otining ll the vitmins their odies needed. It ws proposed they could convert sufficient mounts of the et-crotene contined in their green forge to meet their vitmin A requirement dequtely; tht the ultrviolet rys of the sun would convert ftty sustnces just under their hide to meet their vitmin D requirements dequtely; tht the mrvelous microes of the rumen should synthesize dequte levels of the B vitmins, plus vitmin K; nd finlly, there should e sufficient vitmin E in their diet to meet tht requirement. There re exceptions to this supposition. Thimin (vitmin B1). Although cttle should e le to mnufcture sufficient mounts of this vitmin y their rumen microes, there re times especilly under feedlot conditions when reltive B1 deficiency my exist. Under such condition, mldy known s polio-encephlomlci my occur, ut only in limited numers of cttle. This condition lso is known s circling disese, ecuse fflicted cttle tend to wlk imlessly in circles. The condition seems to occur most on corn silge diets nd is cused y n enzyme clled thiminse, mening it is n orgnism tht locks the norml functioning of thimin. A sudden fll to the ground, followed y scissoring ction with the legs, then deth, chrcterizes this condition. An intrmusculr injection of vitmin B1 will give lmost instntneous relief, nd clf will jump to its feet nd strt cting like the rest of the clves in the pen very shortly. As with coproducts, high concentrtions of sulfur in the feed or wter cn

6 4. Nutrient requirements for eef cows,,c Month since clving NEm required, Mcl per dy d Mintennce Lcttion Pregnncy Totl Metolizle protein required, l. per dy d Mintennce Lcttion Pregnncy Totl Clcium required, g per dy d Mintennce Lcttion Pregnncy Totl Phosphorus required, g per dy d Mintennce Lcttion Pregnncy Totl Gin in weight from pregnncy, l. per dy d Milk, l. per dy Bodyweight, l. per dy Shrunk weight 1,172 1,172 1,172 1,172 1,172 1,172 1,172 1,172 1,172 1,172 1,172 1,172 Conceptus Totl 1,172 1,172 1,174 1,174 1,179 1,181 1,187 1,198 1,214 1,236 1,269 1,313 Adpted from 7th rev. ed., Nutrient Requirements of Beef Cttle, 1996, Ntionl Reserch Council. Crystlline vitmin A should e dded t level of 1,100 IU/l. DM. c Mture weight, 1,173 l.; clf irth weight, 88 l.; ge t clving, 5 yers; ge t wening, 30 weeks; pek milk, 17.6 l.; reed, Angus; milk ft, 4%; milk protein, 3.4%; clving intervl, 12 months. d No llownces mde for gin since this mture cow. cuse this disese with production of hydrogen sulfide in the rumen nd sorption in the loodstrem. This condition does not occur very often nd should not discourge feeders from utilizing corn silge or co-products in their feeding progrms. Vitmin B12. Vitmin B12 should e synthesized in dequte quntities in the ovine rumen. Mny reserch studies hve demonstrted performnce improvement in cttle especilly those on high-energy diets. Perhps the ility of the rumen to synthesize vitmin B12 is orderline, t est. Vitmin A. Green nd yellow feeds contin et-crotene, which is the precursor of vitmin A. In other words, mny nimls possess the cpility to convert et-crotene to meet their vitmin A needs. However, it is now known tht, under certin conditions, the eef niml is not cple of converting sufficient et-crotene to meet its vitmin A needs. It is sfe recommendtion to supply the mjority of the vitmin A needs of eef cttle in the crystlline form. Fortuntely, vitmin A is not very expensive. Vitmin E. Sometimes, condition occurs in clves clled white muscle disese. This condition is ttriuted to deficiency of vitmin E, selenium or oth. Mny cttle producers mke it prctice to inject young clves with comintion of vitmin E nd selenium. Most feeds consumed y cttle except in erly clfhood re dequte in vitmin E. However, reserch hs shown tht incresing concentrtions of vitmin E during the receiving period for newly received eef clves my decrese the incidence of ovine respirtory disese. Furthermore, supplementl vitmin E to feedlot cttle will increse the shelf-life of eef in the grocery met cse. Commodities Grins. Increses in fuel ethnol production nd high fuel prices hve drmticlly incresed the costs of commodities used in cttle feeding. The primry grins used for ethnol production re corn nd sorghum. Aleit prices hve incresed, corn continues to e the primry cerel grin used y consulting feedlot nutritionists (Vsconcelos nd Glyen, 2007). In this survey, whet ws used most often y nutritionists tht used secondry grins, followed y sorghum nd rley. Six nutritionists did not use secondry grin sources. Grin co-products. As result of incresed fuel ethnol production, grin co-products hve ecome common ingredients in eef cttle diets. This is, however, gretly dependent on loction of the milling fcility nd feedlot, prticulrly wet milling fcilities. Of the feedlot consulting nutritionists 5. Minerl requirements nd mximum tolerle levels for eef cttle, Requirement Mximum Growth nd Erly tolerle Minerl finishing Gesttion lcttion level Chlorine, % Chromium, ppm Colt, ppm Copper, ppm Iodine, ppm Iron, ppm Mgnesium, % Mngnese, ppm ,000 Molydenum, ppm 5 Nickel, ppm 50 Potssium, % Selenium, ppm Sodium, % Sulfur, % Zinc, ppm Adpted from 7th rev. ed., Nutrient Requirements of Beef Cttle, 1996, Ntionl Reserch Council. Requirements for clcium nd phosphorus re not included since they re listed in ech of the nutrient requirement tles. Septemer 14, 2011, Feedstuffs 35

7 surveyed y Vsconcelos nd Glyen (2007), 82.76% reported using grin co-products with wet distillers grins most common, followed y dry distillers grins with solules (corn nd/or sorghum), wet corn gluten feed nd dry corn gluten feed. Level of inclusion in finishing diets rnged from 5% to 50% (verge 16.5%; mode = 20%). It should e pointed out, however, tht concentrtions of sulfur in these co-products should e monitored. One dete tht remins is the level of inclusion nd crcss merit. Roeer et l. (2005; J. Anim. Sci. 83: ) reported tht feeding up to 50% distillers grins did not ffect tenderness or sensory trits of strip loins from Holstein steers. Liquid feeds. Ft is dded to finishing diets from 0% to 4.5%; (men = 3.1%; mode = 3.0%; Vsconcelos nd Glyen, 2007). Common ft sources included tllow, yellow grese, choice white grese nd lend of sources. In ddition, 32.4% of clients dded non-ft liquids to the diet. The nonft liquids identified in the survey included corn distillers solules used most often, followed y molsses, molsses lends nd corn distillers solules in comintion with lends (Vsconcelos nd Glyen, 2007). Roughge source nd level. Roughge is commonly dded to finishing diets in smll mounts (0-13.5%; drymtter sis) nd my vry with seson (Vsconcelos nd Glyen, 2007). Just s with other commodities, roughge sources vry with locle. In one survey (Glyen nd Gleghorn, 2001; ville t urnett_center/progress_reports/c12.pdf), the primry roughge source used ws lflf hy (68%), ut more recent survey y Vsconcelos nd Glyen (2007) indicted tht corn silge ws the most common roughge source. The lter uthors suggested tht perhps the more recent survey included roder geogrphicl re nd more consultnts were from midwestern cttle feeding res. Other common roughge ingredients include grss hys, other silges 7. Beef reed mintennce requirements 1 Pek milk --Birth weight production/dy Breed Code NEm kg l. kg l. Angus Brford Brhmn Brngus Brunvich Chrolis Chinin Devon Gllowy Gelvieh Hereford Holstein Jersey Limousin Longhorn Mine Anjou Nellore Piedmontese Pinzgur Polled Hereford Red Poll Shiwl Slers Snt Gertrudis Shorthorn Simmentl South Devon Trentise Adpted from the Ntionl Reserch Council, Nutrient Requirements of Beef Cttle, 7th rev. ed., Feedstuffs, Septemer 14, Formultion informtion for finishing diets (DM sis) used y the consulting nutritionists surveyed y Vsconcelos nd Glyen (2007) Mjor minerls, % Men n Minimum Mximum Mode Clcium Phosphorus Is phosphorus dded? 24 (82.8%) = No 5 (17.2%) = Yes Mgnesium Potssium Sulfur Slt Trce minerls, mg/kg Copper Zinc Mngnese Iron Selenium Iodine Colt Vitmins, IU/kg A 5, , , ,409.2 E D , Reproduced from Vsonelos nd Glyen: Nutritionl recommendtions of feedlot consulting nutritionists: The 2007 Texs Tech University survey. J. Anim Sci. 85: (whet, nd grsses) nd yproducts (cottonseed hulls, cotton urrs, etc.). Supplementtion During certin times of the yer, supplementtion of grzing cttle my e necessry. Supplements re normlly clssified s either protein or energy sed on crude protein concentrtion. Protein supplements contin higher concentrtion of protein (normlly more thn 25%) nd energy supplements contin normlly less thn 18% crude protein. It is generlly recommended tht cttle grzing dormnt mture forges e supplemented. Protein supplements re generlly fed to these cttle. When the crude protein concentrtion of the forge is less thn 6-7%, protein supplementtion cn e used to increse forge intke. The microes will rek down the protein into mino cids nd mmoni nd then utilize the mmoni for use in microil synthesis nd fier digestion will e improved. Pssge rte is then incresed nd intke cn e incresed. Supplementtion with non-structurl crohydrtes often decreses fier digestion nd forge intke. Severl fctors hve een proposed for the decresed digestion including: decrese in ph s result of incresed VFA production therey negtively ffecting growth of ph sensitive firolytic cteri, competition etween cteri for the strch nd/ or preferentil use of the non-structurl crohydrtes y firolytic cteri nd the ssocited increse in lg time. Regrdless, energy or protein supplementtion in growing steers hs een oserved to improve gins ove unsupplemented steers in grss psture. Use of yproduct feedstuffs is n lterntive to using cerel grins. Products such s soyen hulls, whet middlings, corn gluten feed, etc., hve more fier nd less strch thn the unprocessed feed. In ddition, the fier components re generlly highly digestile nd higher in digestiility thn forge fier. Therefore, use of yproduct feedstuffs hs incresed forge intke nd digestiility. Feeding ehvior While we hve the ility to provide proper nutrition through vrious feedstuffs nd grzing mngement, it is ultimtely

8 up to the niml to decide wht nd how it ets. Cttle re gregrious in nture nd depend on socil hierrchy. In terms of feeding ehvior, dominnt nimls essentilly get first choice. For exmple, the pecking order within feedlot pen delinetes tht the more dominnt nimls et first if unk spce is limiting. For grzing cttle, dominnt nimls et wht is most desirle first, which is often the supplement. Suordinte cttle must wit their turn t the trough or consume forge tht is less desirle nd nutritious. Individul nd lerned feeding ehvior lso ply prt in niml nutrition. Any cttle producer cn ttest tht some cttle prefer prticulr feedstuff, while others my prefer nother. Diry cttle re notorious for sorting diets, which is one reson they re more prone to cidotic episodes compred to eef cttle. Beef clves lern grzing ehvior nd plnt selection from oth mother nd experimenttion, which my led to preference for either riprin or non-riprin plnt species. Plcement of wter nd supplements cn lso influence grzing distriution nd essentilly plnt consumption; cttle re willing to trvel wy from wter source for supplement consumption, including ove riprin res nd in more rugged terrin. Essentilly, feeding ehvior on socil nd individul level cn influence nutrient intke nd susequent performnce. Breed multiplier for mintennce requirements. Tles 1, 2, 3 nd 4 present the nutrient requirements for production nd mintennce for vrious eef production situtions. Nturlly, mintennce requirements re tied to severl situtions, including ody size nd hir cot thickness. Those requirements set forth in the tles were intended for the Angus reed of cttle. The NRC committee tht prepred the recommendtions pulished in the 1996 requirements mde recommendtions for djustments tht need to e mde for vrious reeds. These re presented in Tle 7. As my e noted, these djustments represent chnges in mintennce requirements, since requirements for gin nd production re not ffected y ody size. As n exmple, NEm for Holstein cttle (Code No. 12, Tle 7) would e 1.20 times s gret s for Angus (Code No. 1), wheres NEg would e the sme for either reed. Tle 7 lso contins nticipted irth weights nd pek milk yields for the vrious reeds of cttle. Feed Anlysis Tles. A specil section in this Reference Issue contins tles of feed nlyses tht represent verge vlues for ll the feedstuffs used commonly in feed formultion. However, cution must e exercised in formulting lest-cost rtions in which proposed requirements represent miniml levels. A recent study conducted simultneously over three-yer period t 15 stte experiment sttions compred the chemicl nlyses for corn nd soyen mel (J. Anim. Sci : ). Among the corn sources, the rnge in protein nlysis ws from 7.31% to 9.06% (ir-dry sis), representing 24% increse from low to high. Similrly, over two-yer period, for nine stte sources for soyen mel there ws rnge of % protein (ir-dry), representing n increse just greter thn 4% from lowest to highest. Finlly, to demonstrte tht ll corn is not like, some of the newer geneticlly engineered vrieties re quite different. One of the newer such high-oil corns contins 6.5% more crude protein (9.83% versus 9.23%, dry-mtter sis), 82.6% more oil, 5.1% more totl digestile nutrients for eef nd 58% more tocopherols thn typicl dent corn. Formulting rtions It is recommended tht the reder refer to the Feed Ingredient Anlysis Tle in this issue for nlyses of potentil feedstuff inclusion in eef cttle rtions. - Tom Hrms, Generl Mnger, RPA Frmers Coopertive. FOCUSED ON OUR CUSTOMERS, POSITIONED FOR THE FUTURE. Foremost Frms USA the lrgest coopertively owned diry processor hedqurtered in Wisconsin needed cpitl to implement old shift in their usiness strtegy. It ws difficult decision to shift from the consumer products usiness to focus on other strtegic growth opportunities within the diry industry. They sought support from CoBnk, the compny s long-term lending prtner. Our commitment to serving rurl Americ hs never een stronger thn it is tody. We remin dedicted to Americn griusiness nd re proud of the strength nd spirit of our customers. These projects relly ccommodte the growth in supply nd position us to meet the mrket demnd for our products Dve Fuhrmnn, President, Foremost Frms USA Septemer 14, 2011, Feedstuffs 37