REVIEWING NUTRIENT DELIVERY FROM BIRTH TO WEANING. Mike Van Amburgh Department of Animal Science Cornell University, Ithaca, NY TAKE HOME MESSAGES

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1 REVIEWING NUTRIENT DELIVERY FROM BIRTH TO WEANING Mike Vn Amurgh Deprtment of Animl Science Cornell University, Ithc, NY TAKE HOME MESSAGES 1. The pre-wening period is period of life where the clf is undergoing significnt developmentl chnges nd this development is directly linked to future productivity in the first nd susequent lcttions. 2. Pre-wening growth rte nd primrily protein ccretion ppers to e key fctor in signling the tissue or communiction process tht enhnces lifetime milk yield. 3. Anything tht detrcts from feed intke nd susequent pre-wening growth rte reduces the opportunity for enhnced milk yield s n dult. 4. Nutrient supply, oth energy nd protein, re importnt nd protein qulity nd digestiility re essentil. 5. There re no sustitutes for liquid feed prior to wening tht will enhnce the effect on long-term productivity. 6. Fctors other thn immunogloulins in colostrum modify feed intke, feed efficiency nd growth of clves nd cn enhnce the effect of erly life nutrient sttus. 7. As n industry nd s nutritionists we need to tlk out metolizle energy nd protein intke nd sttus reltive to mintennce nd stop tlking out liters, kilogrms nd grms of dry mtter, milk, milk replcer, etc. The clf hs discrete nutrient requirements not relted to dry mtter nd liquid volume mesurements. 8. The effect of nurture is mny times greter thn nture nd the pre-wening period is phse of development where the productivity of the clf cn e modified to enhnce the niml s genetic potentil. INTRODUCTION In the lst ten yers, the concept of intensified feeding or ccelerted growth hs ecome topic of interest mong clf risers nd reserchers nd is eing pplied on frms in vrious mngement systems. The vrious mngement pproches involve differences to est mnge nd deliver nutrition nd nutrient intke for the pre-wened clf within the specific frm mngement cpility. There re teleologicl rguments for providing greter supply of nutrients from milk or milk replcer, (e.g. wht would the dm provide) nd there re lso rguments for improving the welfre sttus of clves y following tht concept (Jsper nd Wery, 2002; de Pul Vieir et l., 2008). Further, dt generted over the lst ten yers hs documented positive responses in productivity of clves s dult cttle when fed greter nutrient intke from milk or milk

2 replcer prior to wening. How clf receives nutrients nd how nutrients or nonnutritionl components of vrious dietry fctors impct growth, development nd productivity is still very ctive re of mngement nd reserch nd will e discussed. Lctocrine Hypothesis EARLY DEVELOPMENT AND PRODUCTIVITY It hs een well recognized tht the level of milk yield of n individul is ffected y oth genetic composition s well s environment. The environment contins multiple externl signls tht ffect the development nd expression of the genetic composition of n niml. While in the wom, the mother controls the environment in which the fetus is developing, influencing in this wy the expression of the genetic mteril. The effect nd extent of mternl influence in the offspring s development does not end t prturition, ut continues throughout the first weeks of life through the effect of milk-orn fctors, including colostrum in this definition, which hve n impct in the physiologicl development of tissues nd functions in the offspring. This concept hs een recently descried s the lctocrine hypothesis (Brtol et l., 2008). Conceptully, this topic is not new ut the terminology is useful nd the ility of severl groups to mke direct connection from fctor in milk to developmentl function t the tissue or ehvior level is significnt (Nusser nd Frwley, 1997; Hinde nd Cpitnio, 2010). Dt relting to this topic hs een descried nd discussed y others in neontl pigs (Donovn nd Odle, 1994; Burrin et l., 1997) nd clves (Bumrucker nd Blum, 1993; Blum nd Hmmon, 2000; Ruprich et l. 2000). The impliction of this hypothesis nd these oservtions is tht the neonte cn e progrmmed mternlly nd post-ntlly to enhnce development or lter development of prticulr process. Colostrum s role s nutrient supply nd s lctocrine vehicle Nutrient role To mximize clf survivl nd growth, plsm immunogloulin (Ig) sttus nd thus colostrum mngement is of utmost importnce. This is oviously not new concept nd there re hundreds of ppers descriing the mngement nd iology surrounding colostrum qulity, yield nd Ig sorption y the clf lthough some recent reserch in colostrum hndling nd mngement suggest we cn still mke improvements (Godden, 2008). Until recently, the primry reson colostrum hs een of interest in neontl ruminnts is due to the importnce of supplying Ig s to clves orn without ny nd lcking mture immune system (Wever et l., 2000). Thus, without sufficient levels of Ig s, moridity nd mortlity rtes re incresed. While Ig s re importnt, colostrum provides the neworn clf with much more thn Ig s. There is n undnce of literture descriing some of these other fctors in colostrum nd the role these compounds cn hve in the development of the clf. Given tht clves over time cn produce their own Ig s through exposure to cteri nd viruses, mternl ntiodies from colostrum re trnsient nd n rgument could e mde tht they re not

3 solutely necessry. Minimizing the cteril lod of colostrum is proly one of the mjor mngement concerns with mny frms nd is usully fctor not considered or nlyzed for. Dt demonstrte tht the presence of cteri in the gut prior to colostrum ingestion or in the colostrum reduces the uptke of Ig, thus incresing the incidence of filure of pssive trnsfer (Jmes et l. 1981, Godden, 2008). Thus excellent udder helth nd proper post-hrvest colostrum hndling is s importnt, or even more importnt thn vccintion progrms to minimize neontl nd post wened clf diseses nd deth loss. Further, stndrdiztion or evlution of colostrum with refrctometer to ensure the pproprite solids or protein content is lso importnt. Using clirted Brix refrctometer, minimum of 22% Brix provides good sensitivity nd specificity for Ig levels for fresh nd frozen colostrum ove 50 mg/ml (Bielmnn et l., 2010). Thus, nything ove 22% is dequte for the first feeding for clves nd nything elow 22% should e reserved for lter feedings. Finlly, to determine totl solids with Brix refrctometer, the Brix vlue needs to e converted. An eqution from Moore et l. (2009) cn e used to do this effectively, nd the eqution is: percent totl solids = x (Brix%) Given the regression coefficients, quick clcultion is Brix% + 2 units. An evlution of the use of Brix refrctometer ws recently pulished y Quigley et l. (2012) nd they suggested cut point of 21% ws pproprite for their dt. Colostrum is the first mel nd ccordingly is very importnt in estlishing the nutrient supply needed to mintin the clf over the first dy of life. The mount of colostrum is lwys focused on the ide we re delivering specific mount of immunogloulins (Ig s) to the clf, nd mny times we underestimte the nutrient contriution of colostrum. Further, mny times of yer, we tend to underestimte the nutrient requirements of the clf, especilly for mintennce. For exmple, neworn Holstein clf t 85 ls irth weight hs mintennce requirement of pproximtely 1.55 Mcls ME t 72 F. Colostrum contins pproximtely 2.51 Mcls metolizle energy (ME)/l, nd stndrd feeding rte of 2 qurts of colostrum from ottle contins out 1.5 Mcls ME. Thus, t thermoneutrl conditions, the clf is fed just t or slightly elow mintennce requirements t its first feeding. For comprison, if the mient temperture is 32 F the ME requirement for mintennce is 2.4 Mcls, which cn only e met if the clf is fed pproximtely 1 l of DM or out 3.5 qurts of colostrum. This simple exmple illustrtes one of the recurring issues with dignosing growth nd helth prolems with clves nd tht is the use of volume mesurements to descrie intke insted of discussing energy nd nutrient vlues. Two qurts of colostrum sounds good ecuse tht is wht the ottle might hold, ut it hs little to do with the nutrient requirements of the clf. Mnging the clf for greter intke over the first 24 hours of life is importnt if we wnt to ensure positive energy lnce nd provide dequte Ig s nd other components from colostrum for proper development. For the first dy, t lest 3 Mcls ME (pproximtely 4 qurts of colostrum) would e necessry to meet the mintennce requirements nd lso provide some nutrients for growth. On mny diries this is done

4 vi n esophgel feeder nd the mount dictted y the desire to get dequte pssive trnsfer. Those diries not tue feeding should e encourging up to 4 qurts y 10 to 12 hours nd might e undersupplying Ig s to the clf. Thus, the first step in supplying model diet to clf is to ensure colostrum is fed not only to meet the Ig needs of the clf, ut lso to ensure tht the nutrient requirements re met for the first dy of life. Lctocrine role Colostrum, in comprison with milk, is known to e rich in Ig s (60x cow), s well s hormones nd growth fctors such s relxin (>19x pig), prolctin (18x cow), insulin (65x cow), IGF-1 (155x cow), IGF-2 (7x cow), nd leptin (90x humns) (Odle et l., 1996; Blum nd Hmmon, 2000; Wolinski et l., 2005; Brtol et l., 2008) mong mny other fctors tht hve iologicl ctivity in the neonte. For long period of time, colostrum hs een known to hve mjor effect on the development of the gstrointestinl trct, ut the exct mechnisms re still not well understood. During the first few dys of life in neontl piglets, notle increse in the length, mss, DNA content, nd enzymtic ctivities of certin enzymes (lctse) occurs in the smll intestine for neontes fed colostrum/milk versus control of wter (Widdowson et l. 1976, Burrin et l., 1994). This ws originlly thought to e medited y differences in nutrient intke etween milk nd wter (Burrin et l. 1992). However, other studies hve demonstrted differences etween nimls fed colostrum tht is rich in growth fctors, versus milk with comprle energy vlues (Burrin et l., 1995). Of interest re the studies tht hve descried decresed growth rte nd incresed moridity of clves with low serum immunogloulin sttus (Nocek, et l., 1984; Roinson et l., 1988) nd some hve even indicted tht milk yield during first lcttion cn e ffected (DeNise et l., 1989). Roinson et l. (1988) demonstrted tht clves with higher Ig sttus were le to inctivte pthogens prior to mounting full immune response which llows them to mintin energy nd nutrient utiliztion for growth, wheres clves with low Ig sttus must mount n immune response which cuses nutrients to e diverted to defense mechnisms. How severe is this difference or for how long does it persist? The dt of DeNise et l., (1989) demonstrted tht for ech unit of serum IgG concentrtion, mesured t 24 to 48 hr fter colostrum feeding, ove 12 mg/ml, there ws n 8.5 kg increse in mture equivlent milk. The impliction ws tht clves with lower IgG concentrtion in serum were more susceptile to immune chllenges which impcted long term performnce. Work from Fer et l. (2005) using Brown Swiss clves demonstrted tht the mount of colostrum provided to clves t irth significntly influenced pre-puertl growth rte y over 0.4 l per dy nd the clves receiving greter colostrum showed trend for n dditionl 2,260 ls of milk throughout the second lcttion. The growth rte oservtion ws not unique to this study, ut egs the question if the response ws due to greter feed intke or etter feed conversion efficiency, which ws not mesured in the study. Further, Jones et l. (2004) exmined the differences etween mternl colostrum nd serum-derived colostrum replcement. In tht study, two sets of clves were fed either mternl colostrum or serum-derived colostrum replcement with

5 nutritionl components lnced. The serum-derived colostrum replcer ws developed to provide essentil IgG s to neontl clf; however the colostrum replcer does not generlly contin the other ioctive fctors ntive to colostrum. These two groups were then further seprted into clves fed milk-replcer with or without niml plsm, yielding four different groups. The results demonstrted tht clves fed mternl colostrum hd significntly higher feed efficiency compred to clves fed serum-derived colostrum replcement. The IgG sttus of the clves on oth tretments were nerly identicl, suggesting tht other fctors in colostrum other thn IgG s were importnt in contriuting to the differences. Some of the other components in colostrum, such s insulin, IGF-I, relxin nd other growth fctors nd hormones, might e importnt fctors in developmentl processes; likewise, lck or shortge of them in erly life might lter developmentl functions, leding to chnge in nutrient utiliztion nd efficiency. To exmine this concept, Soeron nd Vn Amurgh (2011) exmined the effect of colostrum sttus on prewening ADG nd lso exmined the effects of vrying milk replcer intke fter colostrum ingestion. Clves were fed either high levels (4 liters) or low levels (2 liters) of colostrum, nd then clves from these two groups were sudivided into two more groups eing fed milk replcer t limited mounts or d liitum. In this study, none of the clves exhiited filure of pssive trnsfer. Compring clves fed 4 liters of colostrum nd d liitum intke of milk replcer versus 2 liters of colostrum nd d liitum intke of milk replcer, clves fed the 4 liters of colostrum demonstrted n 8.5% increse in milk replcer intke, n 18% increse in pre-wening ADG, 12% increse in post-wening feed intke, nd 25% increse in post-wening ADG through 80 dys of life, indicting tht colostrum potentilly ffects ppetite regultion, which enhnces growth nd possily feed efficiency (Tle 1). Therefore, it cn e logiclly concluded tht if colostrum induces chnges in feed efficiency, then the first feeding cn lso potentilly ffect future milk production. A model diet Milk nd milk replcer Does model diet exist? This question hs n ovious nswer ut is difficult question when diet mngement is prt of the solution. Given choice the dm would provide for the clf n idel diet of milk nd then would tech the clf to consume nonmilk feed when the clf ws physiologiclly redy to do so. Thus, the model diet for clf would e whole milk consumed t the level ppetite regultion nd demnd would dictte nd the dm is willing to supply. The most importnt spects of this re the energy nd protein supply this pproch would provide to the clf nd the recognition tht s n industry, we hve to strt pplying nutritionl principles to this group of cttle if we re going to truly strt solving prolems with growth nd helth. The industry hs mde significnt chnges in the lst 10 yers with respect to clf nutrition, helth, nd growth; however we re still often using volume mesurements to descrie intke nd nutrient sttus insted of megclories of energy nd grms of protein. To ensure more idel diet is fed, the ility to discuss clf nutrition in terms of energy vlues nd

6 developing comfort level with tht pproch will enhnce our prolem solving opportunities nd llow us to develop more stndrdized feeding levels reltive to nutrient demnd. Tle 1. Effect of high (4+2 L) or low (2L) colostrum nd d-li (H) or restricted (L) milk replcer intke on feed efficiency nd feed intke in pre nd post-wened clves (Soeron nd Vn Amurgh, 2011). Tretment 1 HH HL LH LL Std dev N Birth wt, kg Birth hip height, cm IgG concentrtion, mg/dl* 2,746 2,480 1,466 c 1,417 c 98 Wening wt, kg c Wening hip height, cm ADG pre-wening, kg c Hip height gin, pre-wening, cm/d ADG irth to 80 d, kg 0.78 c c c Hip height gin, irth to 80 d, cm/d c Totl milk replcer intke, kg DM Grin intke pre-wening, kg ADG/DMI, pre-wening ADG post-wening, kg DMI post-wening, kg/d ADG/DMI post-wening HH = high colostrum, high feeding level, HL = High colostrum, low feeding level, LH = Low colostrum, high feeding level, LL = Low colostrum, low feeding level. Rows with different superscripts differ P < For exmple, whole milk is pproximtely 2.5 Mcls ME per pound of dry mtter (DM) for the verge Holstein nd out 2.6 Mcls ME per pound DM for Jersey. For comprison, pound of 20% CP, 20% ft milk replcer contins 2.15 Mcls ME nd more contemporry milk replcer like 28% CP, 20% ft would contin slightly more energy t 2.22 Mcls ME per pound DM. A Holstein clf with 100 l BW t 68 F will hve mintennce requirement of 1.75 Mcls ME under good mngement conditions (dry, no wind, dequte previous level of nutrient intke). Therefore, to meet mintennce requirements, 0.8 l DM of either milk replcer re needed to meet tht requirement of 1.75 Mcls, nd 0.7 l DM of milk re need to cover the requirement. Idelly, the clf would e fed liquid diet tht is 12.5% c c

7 solids or DM, nd to do this the totl weight would e 6.4 pounds, composed of 0.8 pounds milk replcer DM nd 5.6 pounds of wter. Agin, refrctometer should e employed to ensure tht the concentrtion of the diet is consistent from dy to dy. This is especilly true when feeding wste milk. Recent visits to frms using wste milk s their primry liquid feed for pre-wened clves found rnges in solids content of 8 to 13% with significnt portion elow 11% solids. The liquid volume eing fed on couple of the frms ws quite high, ut due to the lower solids level, the clves were still not receiving the mount of megclories the mnger ws trgeting. To ccount for the difference, milk replcer type product ws employed to stndrdize the solids nd nutrient content of the wste milk. Further, the nutrient content of wste milk should e evluted on regulr sis to understnd nutrient density nd mke djustments when necessry. The dt from Soeron et l. (2012) nd Soeron nd Vn Amurgh (2013) demonstrte tht chieving dequte pre-wening nutrient intke ove mintennce to promote growth significntly enhnces first nd susequent lcttion milk yield. The liner eqution from the met-nlyses of current studies indictes 1,500 l of first lcttion milk for every one pound of pre-wening verge dily gin. Thus, ensuring dequte nd consistent nutrients ove mintennce requirements enhnces longterm productivity. The nutrient requirements for growth of pre-wened clves were descried in the 2001 Diry NRC (NRC, 2001) nd redefined y Vn Amurgh nd Drckley (2005). The mount of megclories required to chieve specific growth trgets re descried in Tle 2. The first step is to clculte the vlue of the mintennce requirement nd then provide dditionl nutrients ove tht requirement for growth. For exmple, 120 l clf under conditions of some cold stress (20 F) will require 3.4 Mcls ME to meet the mintennce requirement. To chieve 1.5 l/d of ody weight gin, the clf would need to consume 5.8 Mcls of ME which results in 2.4 Mcls ville for gin. The protein requirements would e out 240 g/d of CP to meet the energy llowle growth. To chieve this gin, if feeding stndrdized wste milk, the clf would need to consume out 2.5 gllons per dy. This cn e mngement chllenge for the mnger nd the clf, especilly in twice dy feeding systems due to the volume required. However it is importnt to focus on the energy requirement for the given conditions nd work to ensure the energy vlues re met nd trgets re estlished for growth during ll environmentl conditions. Without trgets nd pro-ctive decision mking long with monitoring, there is little ility to evlute performnce nd mke the pproprite chnges. It is lso importnt to egin to recognize nd pprecite the energy vlues required to chieve the growth trgets nd ojectives tht fit our current understnding of clves growth potentil long with the implictions for long-term productivity.

8 Role of clf strter There is no dete out the role of clf strter in promoting rumen development nd growth of clves. It is essentil tht the clf lern to consume strter nd develop functionl rumen y the time the wening process is completed. Bsic requirements for strter intke prior to complete wening would suggest tht clves e consuming t lest 2 pounds of strter y the time liquid feed is removed. Recent work hs investigted the role of hy prior to wening (Khn et l., 2011; Cstells et l., 2012), nd the type of strter, textured or pelleted, tht enhnces feed intke nd clf growth nd development without compromising rumen helth nd digestiility (Bch, 2013; Kertz, 2013). There re severl fctors t ply when evluting these studies nd their implictions. Behvior is most likely the primry fctor ffecting mjority of the studies tht hve evluted clf strter intke nd preferences. A clf under nturl conditions would lern to consume feed from the dm nd e encourged nd tught to do so s it developed nd ecme physiologiclly redy for tht type of diet. Severl studies hve een conducted on feeding ehvior of grzing nimls nd it is cler tht the dm teches the clf wht to et nd how to et under those mngement conditions (Howery, L. D., et l. 1998; Provenz, 2005). Under most of the conditions we offer clves strter grin, there re rriers to lerning tht ffect the how the clf views nd ccepts the strter grin s food source. Our wy of mnging tht lerning hs een to limit the nutrients from milk or milk replcer in n effort to enhnce hunger so they re encourged to consume nutrients from other sources. Hving clves of somewht vrying ges in group housed conditions helps with the lerning process ecuse the older clves provide lessons in eting ehvior for the clves not yet experienced enough to understnd where nd wht the strter grin might e. Creting n environment tht llows clves to tech ech other out strter grin intke is essentil to enhnce nutrient delivery nd wening efficiency in diry clves nd help void ny post-wening energy lnce prolems. Adding flvors nd odors to strter grin helps this process, especilly for clves fed grin in situtions where they receive no visul feedck out wht other clves re doing. The chemicl composition of the strter is lso importnt. The dete out textured versus pelleted is helpful in sorting out other fctors tht impct intke nd rumen helth. The reserch on ddition of forge to the diet prior to wening lso provides food for thought, ut outside of reserch conditions, this is very difficult to mnge on lrge scle clf rnch. One opportunity is to evlute some of the yproducts used in the development of the strter nd consider those yproducts or ingredients tht supply crohydrtes high in solule fier, such s citrus, eet pulp or lmond hulls. These feeds re reltively high in NDF, nd contin resonly high level of solule fier (pectins) tht re rpidly fermentle, hve high wter holding cpcity (swells), hve ction exchnge cpcity (will sor hydrogen ions) to help uffer the rumen nd re generlly pltle. Those ingredients re not very good for pelleting, ut re comptile with strter grin production nd would provide controlled mount of NDF nd fermentle crohydrte nd would more esily tke the plce of the chopped or

9 processed hy nd e more mngele in mny of our feeding systems. The dt from Cstells et l. (2012) nd Montoro et l. (2013) suggest tht chopped dry hy is helpful for rumen helth, feed intke nd overll clf performnce. An equivlent mount of NDF from one of the ove yproducts should provide similr enefits nd e esier to mnge. Previous work with Agwy indicted tht inclusion of 7 to 15% citrus or eet pulp long with solule fier levels of pproximtely 7% to 8% were useful in enhncing feed intke nd feed efficiency. Soyhulls re not sustitute nd will cuse dirrhe if the inclusion level is too high. SUMMARY Erly life events pper to hve long-term effects on the performnce of the clf. Our mngement pproches nd systems need to recognize these effects nd cpitlize on them. Improving the nutrition nd mngement of clves ppers to improve the sustinility of the niml through incresed productivity throughout life nd this hs implictions for welfre nd the environment long with profitility. We hve much to lern out the consistency of the response nd the mechnisms tht re eing ffected. Given the mount of vrition ccounted for in first nd susequent lcttion milk yield, there re opportunities to enhnce the response once we understnd those fctors. The ottom line is there ppers to e positive economic outcome s dults y improving the mngement of our clf nd heifer progrms strting t irth. REFERENCES Bch, A Does the Physicl Form of the Feeds Offered to Young Clves Mke Difference in Performnce? 25th DISCOVER Conference on Food Animl Agriculture: New Developments in Immunity, Nutrition, nd Mngement of the Preruminnt Clf Brtol, F. F., A. A. Wiley, nd C. A. Bgnell Epigenetic progrmming of porcine endometril function nd the lctocrine hypothesis. Reprod. Domest. Anim. 43: Bumrucker, C. R., nd J. W. Blum Secretion of insulin-like growth fctors in milk nd their effect on the neonte. Livest. Prod. Sci.35: Bielmnn V, Gilln J, Perkins NR, Skidmore AL, Godden S, Leslie KE: An evlution of Brix refrctometry instruments for mesurement of colostrum qulity in diry cttle. J Diry Sci 2010, 93: Blum, J. W., nd H. Hmmon Colostrum effects on the gstrointestinl trct, nd on nutritionl, endocrine nd metolic prmeters in neontl clves. Livest. Prod. Sci. 66: Burrin, D. G., R. J. Shulmn, R. J. Reeds, T. A. Dvis, nd K. R. Grvitt Porcine nd milk stimulte viscerl orgn nd skeletl muscle protein synthesis in neontl piglets. J. Nutr. 122: Burrin, D. G., M. A. Dudley, P.J. Reeds, R. J. Shulmn, S. Perkinson, nd J. Rosenerger Feeding colostrum rpidly lters enzymtic ctivity nd the

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