Productive efficiency of dairy cattle

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1 Sida 1 av 19 Take home messages 1. The pre-weaning period is a period of life where the calf is undergoing significant developmental changes and this development is directly linked to future producvity in the first and subsequent lactaons. 2. Pre-weaning growth rate and primarily protein accreon appears to be a key factor in signaling the ssue or communicaon process that enhances life-me milk yield. 3. Anything that detracts from feed intake and subsequent pre-weaning growth rate reduces the opportunity for enhanced milk yield as an adult. 4. Nutrient supply, both energy and protein are important and protein quality and digesbility are essenal. 5. There are no substutes for liquid feed prior to weaning that will enhance the effect on long-term producvity. 6. Factors other than immunoglobulins in colostrum modify feed intake, feed efficiency and growth of calves and can enhance the effect of early life nutrient status. 7. As an industry and as nutrionists we need to talk about metabolizable energy and protein intake and status relave to maintenance and stop talking about liters, kilograms and grams of dry maer, milk, milk replacer etc. The calf has discrete nutrient requirements not related to dry maer and liquid volume measurements. 8. The effect of nurture is many mes greater than nature and the pre-weaning period is a phase of development where the producvity of the calf can be modified to enhance the animal s genec potenal. Introduction Research, publicaons and farm level management related to the topic of calves and calf management over the last 40 years tradionally involved dry cow management, colostrum, diarrhea, rumen development and early weaning. In the last ten years, the concept of intensified feeding or accelerated growth has become a topic of interest among calf raisers and researchers and is being applied on farms in various management systems. The various management approaches involve differences in to best manage and deliver nutrion and nutrient intake for the pre-weaned calf to opmize the specific farm management capability. There are teleological arguments for providing a greater supply of nutrients from milk or milk replacer, e.g. what would the dam provide, and there are also arguments for improving the welfare status of calves by following that concept (Jasper and Weary, 2002; de Paula Vieira et al., 2008). Further, data generated over the last ten years has documented posive responses in producvity of calves as adult cale when fed greater nutrient intake from milk or milk replacer prior to weaning and this will be discussed. Early development and productivity Lactocrine Hypothesis It has been well recognized that the level of milk yield of an individual is affected by both genec composion as well as environment. The environment contains mul- ple external signals that affect the development and expression of the genec composion of an animal. While in the womb, the mother controls the environment in which the fetus is developing, influencing in this way the expression of the genec material. The effect and extent of maternal influence in the offspring s development does not end at parturion, but connues throughout the first weeks of life through the effect of milk-born factors, including colostrum in this definion, which have an impact in the physiological development of ssues and funcons in the offspring. This concept has been recently described as the lactocrine hypothesis (Bartol et al., 2008). Conceptually, this topic is not new but the terminology is useful and the ability of several groups to make a direct connecon from a factor in milk to a developmental funcon at the ssue or behavior level is significant (Nusser and Frawley, 1997; Hinde and Capitanio, 2010). Data relang to this topic has been described and discussed by others in neonatal pigs (Donovan and Odle, 1994; Burrin et al., 1997) and calves (Baumrucker and Blum, 1993; Blum and Hammon, 2000; Rauprich et al. 2000). The implicaon of this hypothesis and these observaons are that the neonate can be programmed maternally and post-natally to alter development of a parcular process. Colostrum s role Colostrum, in comparison with milk, is known to be rich in immunoglobulins (60x cow), as well as hormones and growth factors such as relaxin (> 19x pig), prolac- n (18x cow), insulin (65x cow), IGF-1 (155x cow), IGF-2 (7x cow), and lepn (90x humans) (Odle et al., 1996; Blum and Hammon, 2000; Wolinski et al., 2005; Bartol et al., 2008) among many other factors that have biological acvity in the neonate. For a long period of me, colostrum has been known to have a major effect on the development of the gastrointesnal tract, but the exact mechanisms are sll not well understood. During 12 Djurhälso- och Uodringskonferensen 2016

2 Sida 2 av 19 the first few days of life in neonatal piglets, a notable increase in the length, mass, DNA content, and enzyma- c acvies of certain enzymes (lactase) occurs in the small intesne for neonates fed colostrum/milk versus a control of water (Widdowson et al. 1976, Burrin et al., 1994). This was originally thought to be mediated by differences in nutrient intake between milk and water (Burrin et al. 1992). However, other studies have demonstrated differences between animals fed colostrum that is rich in growth factors, versus milk with comparable energy values (Burrin et al., 1995). Of interest are the studies that have described decreased growth rate and increased morbidity of calves with low serum immunoglobulin status (Nocek, et al., 1984; Robinson et al., 1988) and some have even indicated that milk yield during first lactaon can be affected (DeNise et al., 1989). Robinson et al. (1988) demonstrated that calves with higher Ig status were able to inacvate pathogens prior to mounng a full immune response which allows them to maintain energy and nutrient ulizaon for growth, whereas calves with low Ig status must mount an immune response which causes nutrients to be diverted to defense mechanisms. How severe is this difference or for how long does it persist? The data of DeNise et al., (1989) demonstrated that for each unit of serum IgG concentraon, measured at 24 to 48 hr aer colostrum feeding, above 12 mg/ml, there was an 8.5 kg increase in mature equivalent milk. The implicaon was that calves with lower IgG concentraon in serum were more suscepble to immune challenges which impacted long term performance. As with all longitudinal and epidemiological studies there are inconsistencies. Work from Faber et al. (2005) using Brown Swiss calves demonstrated that the amount of colostrum provided to calves at birth significantly influenced pre-pubertal growth rate by over 0.2 kg per day and the calves receiving greater colostrum showed a trend for an addional 1,027 kg of milk throughout the second lactaon. The growth rate observaon was not unique to this study, but begs the queson if the response was due to greater feed intake or beer feed conversion efficiency, which was not measured in the study. Some of the other components in colostrum, such as insulin, IGF-I, relaxin and other growth factors and hormones, might be important factors in developmental processes; likewise, a lack or shortage of them in early life might alter developmental funcons, leading to a change in nutrient ulizaon and efficiency. To examine this concept, Soberon and Van Amburgh (2011) examined the effect of colostrum status on pre-weaning ADG and also examined the effects of varying milk replacer intake aer colostrum ingeson. Calves were fed either Table 1. Effect of high (4+2 L) or low (2L) colostrum and ad-lib (H) or restricted (L) milk replacer intake on feed efficiency and feed intake in pre and post-weaned calves (Soberon and Van Amburgh, 2011). Treatment1 HH HL LH LL Std dev N Birth wt, kg Birth hip height, cm IgG concentraon, mg/dl* 2,746 a 2,480 b 1,466 c 1,417 c 98 Weaning wt, kg 78.2 a 63.5 b 72.2 c 62.4 b 1.89 Weaning hip height, cm 93.0 a 88.6 b 91.5 a 89.6 b 0.60 ADG pre-weaning, kg 0.79 a 0.42 b 0.67 c 0.39 b Hip height gain, pre-weaning, cm/d a b a b ADG birth to 80 d, kg 0.78 a 9 bc 0.66 b 0.53c Hip height gain, birth to 80 d, cm/d a b c b Total milk replacer intake, kg DM 44.4 a 20.5 b 40.9 c 20.0 b 1.2 Grain intake pre-weaning, kg 2.5 a 12.0 b 2.1 a 9.7 b 1.5 ADG/DMI, pre-weaning ADG post-weaning, kg 1.10 a 0.97 ab 0.88 b 0.92 b DMI post-weaning, kg/d 2.89 ab 2.89 a 2.58 c 2.66 bc ADG/DMI post-weaning 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 < Djurhälso- och Uodringskonferensen

3 Sida 3 av 19 high levels (4 liters) or low levels (2 liters) of colostrum, and then calves from these two groups were subdivided into two more groups being fed milk replacer at limited amounts or ad libitum. In this study, none of the calves exhibited failure of passive transfer. Comparing calves fed 4 liters of colostrum and ad libitum intake of milk replacer versus 2 liters of colostrum and ad libitum intake of milk replacer, calves fed the 4 liters of colostrum demonstrated an 8.5% increase in milk replacer intake, an 18% increase in pre-weaning ADG, a 12% increase in post-weaning feed intake, and a 25% increase in postweaning ADG through 80 days of life, indicang that colostrum potenally affects appete regulaon, which enhances growth and possibly feed efficiency (Table 1). Nutrient status There are several published studies and studies in progress that have both directly and indirectly allowed us to evaluate milk yield from cale that were allowed more nutrients up to eight weeks of age (Table 2). The earliest of these studies invesgated either the effect of suckling versus controlled intakes or ad-libitum feeding of calves from birth to 42 or 56 days of life (Foldager and Krohn, 1994; Bar-Peled et al, 1997; Foldager et al, 1997). In each of these studies, increased nutrient intake prior to 56 days of life resulted in increased milk Table 2. Milk producon differences as adults among treatments where calves were allowed to consume approximately 50% more nutrients than the standard feeding rate prior to weaning from either milk or milk replacer. Study Milk response (kg) Foldager and Krohn, ,405 s Bar-Peled et al., t Foldager et al., t Ballard et al., 2005 (@ 200 DIM) 700 s Shamay et al., s Drackley et al., s Raeth-Knight et al., ns Terre et al., ns Morrison et al., ns Moallem et al., s Davis-Rincker et al., ns Soberon et al., s Margerison et al., s Kinzelback et al., ns Milk response is the difference between treatment milk yield minus control s P < 0.05, t P < 0.1, ns P > 0.1 yield during the first lactaon that ranged from 450 to 1,361 addional kilograms compared to more restricted fed calves during the same period (Table 2). Although they are suckling studies, milk is most likely not the factor of interest, but nutrient intake in general and this is demonstrated in the more recent data. A meta-analysis was conducted to evaluate the data presented in Table 2 using Comprehensive Meta-Analysis soware (CMA, v , Biostat, Englewood, NJ; Borenstein et al., 2005). In the first analysis, the treatment calves, or those calves that received more nutrients from milk or milk replacer prior to weaning, were esmated to produce 429 ± 106 kg more milk in first lactaon (P < 0.001) compared to control calves. This analysis did not include ADG or any other predictor and was simply an evaluaon of treatment effect. It should be immediately recognized that within these data sets, starter intake was not well described and any starter intake or addional nutrient intake would enhance the outcome, but is difficult to quanfy. In the paper by Soberon et al. (2012) the role of starter intake was discussed and based on recent studies invesgang starter intake and growth rates, it would be very difficult for calves to achieve the nutrient intakes and associated growth rates in the first 4 to 6 wk of life necessary to realize the milk yield outcome idenfied in this analysis. Equally important was the odds rao from this analysis of 2.09 (P = 0.001) which indicated that a calf receiving more nutrients during the pre-weaning period was two mes more likely to produce more milk that a calf that is restricted during the same period. Each study offered different quanes and qualies of nutrients to treatment groups, thus to help evaluate the outcome of milk yield, ADG was included in the analysis to account for the effect of nutrient intake and nutrient quality. In order to evaluate the effect of ADG on first lactaon milk yield, ADG was included in the analyses as a predictor variable and analyzed by metaregression. In that analyses, a predicon equaon was generated where first lactaon milk yield = -106 kg + 1,551.4 (± 637) kg*adg (Low limit 301 kg, upper limit 2,801 kg; Z value 2.41; P = 0.01), where ADG is kg preweaning average daily gain. This means that for every kg of pre-weaning ADG, calves produced 1,551 kg more milk during their first lactaon (Soberon and Van Amburgh, 2013). This was a higher but consistent response to what was observed among two herds of 850 kg and 1,113 kg per kg of ADG (Soberon et al., 2012) indicang that the response to pre-weaning nutrient intake is not constant among herd and most likely varies with the management and environment of the herd along with the herd genec potenal for milk yield. 14 Djurhälso- och Uodringskonferensen 2016

4 Sida 4 av 19 The Cornell University Dairy Herd started feeding for greater pre-weaning BW gains many years ago and we have over 1,200 weaning weights and 3+ lactaons with which to make evaluaons outside of our on going study. What makes our approach to this unique is the applicaon of a Test Day Model (TDM) (Evere and Schmitz. 1994; Van Amburgh et al., 1997) for the analyses of the data. This approach allows us to stascally control for factors not associated with the variables of interest and is the same approach that has been used to conduct sire summaries and daughter evaluaons and develop heritabilies for genec traits. Thus, the outcome is mathemacally more robust and allows us to look within a herd over me with less bias and to look at herd responses independent of formal treatments. The resulng residuals are standardized which makes them addive over the life of the animal and they can be calculated for individual test days or over the lactaon. The power of this type of analyses is much more significant compared to comparing daily milk or even ME305 milk and helps us paron out variance not associated with the variables of interest. We analyzed the lactaon data of the 1,244 heifers with completed lactaons using the TDM approach and stascally analyzed several factors related to early life performance and the TDM milk yield residuals (Soberon et al. 2012). The factors analyzed were birth weight, weaning weight, height at weaning, BW at 4 weeks of age and several other related and farm measurable factors. From a management perspecve the most interesng observaon was the relaonship among two factors, growth rate prior to weaning and intake over maintenance and first lactaon milk yield. In these analyses, the strongest relaonship associated with first lactaon milk producon was growth rate prior to weaning and the findings are consistent with the data presented in Table 4. In our data set, for every 1 kg of average daily gain (ADG) prior to weaning (or at least 42 to 56 days of age), the heifers produced approximately 552 kg more milk (P < 0.01). The range in pre-weaning growth rates among the 1,244 animals were 0.24 to 1.25 kg per day which, when analyzed against other farm level data is consistent but was puzzling to us. Our feeding program at the research farm is straighorward: 1.5% BW dry maer from day 2 to 7 and then 2% of BW dry maer from day 8 to 42 of a 28:15 or 28:20 milk replacer mixed at 15% solids. Free choice water is offered year around and starter is offered from day 8 onward. At that feeding rate, we are offering twice the industry standard amount and had assumed it was enough for overcoming the maintenance requirement and provide adequate nutrients for growth, even in the winter. However, when we analyzed the TDM residuals by temperature at birth, a very significant observaon was made (Figure 2). Figure 1. Meta regression of the ADG effect on milk yield response from calves offered more nutrients pre-weaning. Regression equaon: Difference in milk yield means = -106 kg + 1,551.4 kg*adg (P = 0.01) (From Soberon and Van Amburgh, J. Anim. Sci. 2013) Figure 2. Test Day Model residuals in kg of milk, averaged by temperature at me of birth with mean temperature in Celsius. Columns with different superscripts differ (P < 0.05). Djurhälso- och Uodringskonferensen

5 Sida 5 av 19 These data very much suggest that although we are meeng the maintenance requirements of the calves from a strict requirement calculaon, we are not providing enough nutrients above maintenance to opmize first lactaon milk producon. We need to remember that the thermoneutral zone for calves is 20 to 28 C and that when the temperature drops below that level, intake energy will be used to generate heat instead of growth. In addion, when we analyzed the data by lactaon, the response increased as the animals matured (Table 3). Taken together, these data demonstrate there are development or programming events being affected in early life that have a lifeme impact on producvity. When the data were evaluated for the 450 animals that had completed a third lactaon, we found a lifeme milk effect of pre-weaning average daily gain of over 2,200 kg of milk depending on pre-weaning growth rates. Further, 22% of the variaon in first lactaon milk producon could be explained by growth rate prior to weaning. This suggests that colostrum status and nutrient intake and or pre-weaning growth rate have a greater effect on lifeme milk yield and account for more varia- on in milk yield of the calf than genec selecon. Generally, milk yield will increase 70 to 140 kg per lactaon due to selecon whereas the effect of management is three to five mes that of genec selecon In the Cornell herd, the effect of diarrhea or anbioc treatment on ADG was not significant and ADG differed by approximately 30 g/d for calves that had either event in their records (P > 0.1). However, for calves that had both events recorded, ADG was lower by approximately 50 g/d (P < 0.01). Over the eight year period, approximately 59% of all of the calves had at least one of the recorded events. In the data from the Cornell herd, first lactaon milk yield was not significantly affected by reported cases of diarrhea. Anbioc treatment had a significant effect on TDM residual milk and calves that were treated with anbiocs produced 493 kg less milk in the first lactaon (P > 0.01) than calves with no record of being treated. Regardless of anbioc treatment, the effect of ADG on first lactaon milk yield was significant in all calves (P < 0.05). Calves that were treated with anbiocs produced 623 kg more milk per kg of pre-weaning ADG while calves that did not receive anbiocs produced 1,407 kg more milk per kg of pre-weaning ADG. The effect of increased nutrient intake from milk replacer was sll apparent in the calves that were treated, but the lactaon milk response was most likely aenuated due to factors associated with sickness responses and nutrient paroning away from growth funcons (Johnson, 1998; Dantzer, 2006). An analysis of all the lactaon data and the pre-weaning growth rates, when controlled for study, suggests that to achieve these milk yield responses from early life nutrion, calves must double their birth weight or grow at a rate that would allow them to double their birth weight by weaning (56 days). This further suggests that milk or milk replacer intake must be greater than tradi- onal programs for the first 3 to 4 weeks of life in order to achieve this response. Summary Early life events appear to have long-term effects on the performance of the calf. Our management approaches and systems need to recognize these effects and capitalize on them. Improving the nutrion and management of calves appears to improve the sustainability of the animal through increased producvity throughout life and this has implicaons for welfare and the environment along with profitability. We have much to learn about the consistency of the response and the mechanisms that are being affected. Given the amount of variaon accounted for in first and subsequent lactaon milk yield, there are opportunies to enhance the response once we understand those factors. The boom line is there appears to be a posive economic outcome as adults by improving the management of our calf and heifer programs starng at birth. Table 3. Predicted differences by TDM residual milk (kg) for 1 st, 2 nd, and 3 rd lactaon as well as cumulave milk from 1 st through 3 rd lactaon as a funcon of pre-weaning average daily gain and energy intake over predicted maintenance for the Cornell herd. Lactaon n Predicted difference in milk per kg of pre-weaning ADG P value Predicted difference in milk (kg) for each addional Mcal intake energy above maintenance 1 st < < nd < rd < st - 3 nd 450 2, < 0.01 P value 16 Djurhälso- och Uodringskonferensen 2016

6 Sida 6 av 19 References Ballard, C., H. Wolford, T. Sato, K., Uchida, M. Suekawa, Y. Yabuuchi, and K. Kobayashi The effect of feeding three milk replacer regimens preweaning on first lactaon performance of Holstein cale. J. Dairy Sci. 88:22 (abstr.) Bar-Peled, U., B. Robinzon, E. Maltz, H. Tagari, Y. Folman, I. Bruckental, H. Voet, H. Gacitua, and A. R. Lehrer Increased weight gain and effects on producon parameters of Holstein heifers that were allowed to suckle. J. Dairy Sci. 80: Bartol, F. F., A. A. Wiley, and C. A. Bagnell Epigenec programming of porcine endometrial funcon and the lactocrine hypothesis. Reprod. Domest. Anim. 43: Baumrucker, C. R., and J. W. Blum Secreon of insulin-like growth factors in milk and their effect on the neonate. Livest. Prod. Sci. 35: Blum, J. W., and H. Hammon Colostrum effects on the gastrointesnal tract, and on nutrional, endocrine and metabolic parameters in neonatal calves. Livest. Prod. Sci. 66: Borenstein M, Hedges L, Higgins J, Rothstein H. Comprehensive Metaanalysis Version 2, Biostat, Englewood NJ Comprehensive Meta Analyses soware. Burrin, D. G., R. J. Shulman, R. J. Reeds, T. A. Davis, and K. R. Gravi Porcine colostrum and milk smulate visceral organ and skeletal muscle protein synthesis in neonatal piglets. J. Nutr. 122: Burrin, D. G., M. A. Dudley, P.J. Reeds, R. J. Shulman, S. Perkinson, and J. Rosenberger Feeding colostrum rapidly alters enzymac acvity and the relave isoform abundance of jejunal lactase in neonatal pigs. J. Nutr. 124: Burrin, D. G., T. A. Davis, S. Ebner, P. A. Schoknect, M. L. Fioroo, P. J. Reeds, and S. McAvoy Nutrient-independent and nutrient-dependent factors smulate protein synthesis in colostrum-fed newborn pigs. Pediatr. Res. 37: Burrin, D.D., T.A. Davis, S. Ebner, P.A. Schoknecht, M.L. Fioroo, and P.J. Reeds Colostrum enhances the nutrional smulaon of vital organ protein synthesis in neonatal pigs. J. Nutr. 127: Dantzer, R Cytokine, sickness behavior, and depression. Neurol. 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W Immune and endocrine regulaon of food intake in sick animals. Domest Anim. Endocrinol. 15: Moallem, U., D. Werner, H. Lehrer, M. Kachut, L. Livshitz, S. Yakoby and A. Shamay Long-term effects of feeding ad-libitum whole milk prior to weaning and prepubertal protein supplementaon on skeletal growth rate and first-lactaon milk producon. J. Dairy Sci. 93: Nocek, J. E., D. G. Braund, and R. G Warner Influence of neonatal colostrum administraon, immunoglobulin, and connued feeding of colostrum on calf gain, health and serum protein. J. Dairy Sci. 67: Nusser, K. D., and S. Frawley Depriving neonatal rats of milk from early lactaon as long-term consequences on mammotrope development. Endocrine 7: Odle, J., R. T. Zijlstra, and S. M. Donovan Intesnal effects of milkborne growth factors in neonates of agricultural importance. J. Anim. Sci. 74: Raeth-Knight, M., H. Chester-Jones, S. Hayes, J. Linn, R. Larson, D. Ziegler, B. Ziegler and N. 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7 Sida 7 av 19 Soberon F., E. Raffrenato, R. W. Evere and M. E. Van Amburgh Early life milk replacer intake and effects on long term producvity of dairy calves. J. Dairy Sci. 95: Soberon F., and M. E. Van Amburgh Effects of colostrum intake and pre-weaning nutrient intake on post-weaning feed efficiency and voluntary feed intake. J. Dairy Sci. 94:69-70 (Abstr.). Soberon F., and M. E. Van Amburgh The effect of nutrient intake from milk of milk replacer of pre-weaned dairy calves on lactaon milk yield as adults: a meta-analysis of current data. J. Anim. Sci. 91: Terré, M., C. Tejero, and A. Bach Long-term effects on heifer performance of an enhanced growth feeding program applied during the pre-weaning period. J. Dairy Res. 76: Van Amburgh, M. E. and J. K. Drackley Current perspecves on the energy and protein requirements of the pre-weaned calf. Chap. 5 in Calf and heifer rearing: Principles of rearing the modern dairy heifer from calf to calving. Nongham Univ. Press. P.C. Garnsworthy, ed. Pp Van Amburgh, M. E., D. M. Galton, D. E. Bauman, and R. W. Evere Management and economics of extended calving intervals with use of bovine somatotropin. Livest. Prod. Sci. 50: Wolinski, J., M. Biernat, P. Guilloteau, B. R. Weström Exogenous lepn controls the development of the small intesne in neonatal piglets. J. Endo. 177: Widdowson, E. M., V. E. Colombo, and C. A. Artavanis Changes in the organs of pigs in response to feeding for the first 24 h aer birth. II. The digesve tract. Biol. Neonate 28: Djurhälso- och Uodringskonferensen 2016

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19 Sida 19 av 19! Frågor och egna erfarenheter? Vad tar jag med mig? Konsekvenser? Prakska idéer? Vad gör jag konkret? 30 Djurhälso- och Uodringskonferensen 2016