NUTRITION HEALTH AND MANAGEMENT CONSIDERATIONS OF CALF-FED HOLSTEIN STEERS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1005545
• Project Start Date: Jan 29, 2015
• Project End Date: Sep 30, 2019
• Program Code: [(N/A)]- (N/A)

Recipient Organization
UNIVERSITY OF CALIFORNIA, DAVIS
410 MRAK HALL
DAVIS,CA 95616-8671

Performing Department
Animal Science

Non Technical Summary
The practical significance of feedlot diet formulations to meet metabolizable protein requirements of calf-fed Holstein steers will be evaluated. Considering that methionine is the first limiting amino acid during the initial growing period, two trials will be conducted that evaluate metabolizable methionine supplementation as a single amino acid in feedlot diet formulations that are supplemented to meet or exceed expected requirements for metabolizable protein and lysine. In a second series of two trials, the potential protein sparing effects of supplemental virginiamycin on metabolizable protein requirements of calf-fed Holstein steers.

Animal Health Component

80%

Research Effort Categories

Basic

20%

Applied

80%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
302	3440	1010	100%

Knowledge Area
302 - Nutrient Utilization in Animals;

Subject Of Investigation
3440 - Meat, dairy cattle;

Field Of Science
1010 - Nutrition and metabolism;

Keywords

holstein

feedlot

growth-performance

amino acid

lysine

methionine

and virginiamycin.

Goals / Objectives
The objective of this study is be to evaluate nutrition, management and health factors that will optimize growth-performance and carcass characteristics of calf-fed Holstein steers.The objective of the current experiments are: 1) evaluate the influence of metabolizable methionine nutrition of calf-fed Holstein steers during the initial growing phase in the feedlot on overall feedlot growth performance and net energy value of the diet, 2) evaluate protein sparing effect of virginiamycin on early protein nutrition. Changes in growth performance and dietary net energy will be assessed with respect to characteristics of digestive function and estimates of amino acid supply to the small intestine.

Project Methods
Trial 1. Two hundred twenty Holstein steer calves (≈127 kg) will be used to evaluate effects of amino acid nutrition on growth performance and dietary net energy. Treatments will consist of steam-flaked corn-based growing-finishing diets supplemented with (DM basis): 1) no amino acid additive, urea as sole source of supplemental N; 2) 7% protein supplement (high-lysine, blend of blood meal and distillers dried grains) for 105 d followed by treatment 1 until harvest (about 200 d); 3) 0.064% Smartamine and 7% protein supplement first 105 d followed by treatment 1 until harvest; 4) 0.096% Smartamine and 7% protein supplement for first 105 d followed by treatment 1 until harvest; and 5) 0.128% Smartamine and 7% protein supplement for first 105 d followed by treatment 1 until harvest. Steers will be balanced by weight and assigned to 25 pens (8 steers/pen). Steers will be allowed ad libitum access to water and dietary treatments. Fresh feed will be provided twice daily. Hot carcass weights will be obtained from all steers at time of slaughter. After carcasses are chilled for 48 h the following measurements will be obtained: 1) longissimus muscle area (ribeye area), taken by direct grid reading of the muscle at the twelfth rib; 2) subcutaneous fat over the ribeye muscle at the twelfth rib taken at a location 3/4 the lateral length from the chine bone end; 3) kidney, pelvic and heart fat (KPH) as a percentage of hot carcass weight and 4) marbling score (USDA, 1965). Energy gain (EG, Mcal/d) will be calculated by the equation: EG = ADG1.097 .0557W.75 (NRC, 1984). Maintenance energy (EM) will be calculated by the equation: EM = .084 W.75 . Calves will be weighed at 28-d intervals. On d 70, blood samples will be collected from one steer per pen via jugular puncture into heparinized tubes, centrifuged 1,000 g for 10 min, and stored a -20 C for possible amino acid analysis. From the derived estimates of energy required for maintenance and gain, the NEm and NEg values of the diet will be obtained by means of the quadratic formula: x = (-b ± Öb2-4ac)/2c, where a = -0.41EM, b = 0.877EM + 0.41DMI + EG, and c = -0.877DMI, and NEg = 0.877NEm - 0.41 (Zinn and Shen, 1998). For calculating steer performance, live weights will be reduced 4% to account for digestive tract fill. The trial will be analyzed as a randomized complete block design experiment.Trial 2. Five Holstein steers with cannulas in the rumen and proximal duodenum will be used in a 5 × 5 Latin square experiment. Treatments will be the same as in Trial 1, with the incorporation of chromic oxide as a digesta marker. Dry matter intake will be restricted to 2.2% of live weight. Diets will be fed at 0800 and 2000 daily. Experimental periods will consist of a 10-d diet adjustment period followed by a 4-d collection period. During the collection period duodenal and fecal samples will be taken from all steers, twice daily as follows: d 1, 0750 and 1350; d 2, 0900 and 1500; d 3, 1050 and 1650; and d 4, 1200 and 1800. Individual samples consist of approximately 700 ml duodenal chyme and 200 g (wet basis) fecal material. On the final day of each collection period (d 4) blood samples and ruminal fluid will be obtained from each steer 4 h after the morning feeding (1200 h). Blood samples (two vials per steer) will be collected via venipuncture of caudal vein (tail vein) into heparinized sterile vacuum blood collection tubes (Becton Dickinson, Franklin Lakes, NJ). Samples will be immediately placed on ice and centrifuged for 20 min at 1,000 × g. Plasma will be stored at -20o C, and later analyzed for plasma AA. Ruminal fluid (100 mL) will be obtained from each steer via the ruminal cannula. Ruminal fluid pH will be determined on freshly collected samples. Samples will then be strained through 4 layers of cheesecloth. Freshly prepared 25% (wt/vol) m-phosphoric acid (2 mL) will be added to 8 mL of the strained ruminal fluid. Samples will then be centrifuged (17,000 × g for 10 min) and supernatant fluid stored at -20o C for analysis of VFA concentrations (gas chromatography; Zinn, 1988). Duodenal and fecal samples from each steer and within each collection period will be composited for analysis. Upon completion of the trial, ruminal fluid will be obtained from all steers and composited for isolation of ruminal bacteria via differential centrifugation (Bergen et al., 1968). Samples will be subjected to all or part of the following analysis: DM (oven drying at 105 C until no further weight loss); ash, Kjeldahl N, ammonia N (AOAC, 1975); NDF (Goering and Van Soest, 1970; adjusted for insoluble ash), purines (Zinn and Owens, 1986); chromic oxide (Hill and Anderson, 1958), starch (Zinn, 1990), and amino acids (hydrolysis under N in sealed ampules with 6 N HCl overnight at 110°C followed by amino acid analysis using norleucine as an internal standard). Microbial organic matter (MOM) and N (MN) leaving the abomasum is calculated using purines as a microbial marker (Zinn and Owens, 1986). OM fermented in the rumen (OMF) is considered equal to OM intake minus the difference between the amount of total OM reaching the duodenum and MOM reaching the duodenum. Feed N escape to the small intestine is considered equal to total N leaving the abomasum minus ammonia-N and MN and, thus, includes any endogenous contributions. Methane production is calculated based on the theoretical fermentation balance for observed molar distribution of VFA and OM fermented in the rumen (Wolin, 1960). The trial will be analyzed as a 5 x 5 Latin square experiment (Hicks, 1973).Trial 3. One hundred twenty calf-fed Holstein steers (130 kg) will be used in a 112-d trial. Steers will be balanced by weight and assigned to 20 pens (6 steers/pen). Four dietary treatments will be evaluated in a randomized complete block design. Dietary treatments consist of two levels of metabolizable protein (100 vs 87% of expected NRC requirements) supplemented with or without 22.5 mg/kg virginiamycin in a 2×2 factorial arrangement. The low metabolizable protein diet (87% of NRC requirements) is typical of current conventional feedlot formulations. Cattle management and estimation of treatment effects on dietary net energy will be as in Trial 1. The trial will be analyzed as a randomized complete block design. Treatment main effects and interactions will be tested by means of orthogonal contrasts (Hicks, 1973).Trial 4. Four Holstein steers with cannulas in the rumen, proximal duodenum and distal ileam will be used in a 4 × 4 Latin square experiment. Treatments will be the same as in Trial 1, with the incorporation of chromic oxide as a digesta marker. Dry matter intake will be restricted to 2.2% of live weight. Diets will be fed at 0800 and 2000 daily. Experimental periods will consist of a 17-d diet adjustment period followed by a 4-d collection period. Each steer will be bolused with ruminal thermistor for semicontinuous recording of treatment effects on core body temperature. Animal management and sample collection and analysis will be as in Trial 2. The trial will be analyzed as a 4 x 4 Latin square experiment (Hicks, 1973).

Progress 01/29/15 to 09/30/19

Outputs
Target Audience:Animal Nutritionists, Feedlot cattle industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest? Nothing Reported What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Subcutaneous administration is a practical alternative to the traditional intramuscular of administration of injectable vitamin E for calf-fed Holstein steers. Ruminal conditions require about 7 days to stabilize following an abrupt digestive challenge. Feeding low levels (60 g/head) of high-oil algae biomass may enhance daily weight gain of calf-fed Holsteins during periods of high ambient temperature. This effect is due in part to an apparent increase in efficiency utilization and in part to an increased dry matter intake. aolinite supplementation up to 2% of diet OM may enhance energetic efficiency of calf-fed Holstein steers in a manner independent of changes in characteristics of ruminal and total tract digestion. Enhancements in energy utilization when diets are balanced to meet metabolizable amino acid requirements of calf-fed Holstein steers during the initial 112-d feedlot period remain appreciable throughout time on feed. Supplemental virginiamycin enhances efficiency of energy utilization of calf-fed Holsteins throughout the feedlot growing-finishing period. Changes in physical characteristics of wheat straw brought about by pelleting negatively impact OM digestion of both steam­flaked and dry•rolled corn-based finishing diets for Holstein steers. This effect is due to decreased post-ruminal starch digestion. Replacement of ground straw with pelleted straw also may decrease ruminal pH • . Vitamin E supplementation of calf-fed Holstein steers receiving a conventional steam-flaked corn-based growing-finishing diet is not expected to enhance growth performance. Vitamin E supplementation above basal requirements may enhance growth performance during the initial 112-d phase. However, the overall effect on growth performance and carcass characteristics was not appreciable. Injectable retinol ester form did not affect overall ADG, gain efficiency, or dietary NE. Based on plasma retinol concentrations, the bioavailability of retmyl pa1m1tate is greater than that ot retmyl propionate. Tannin supplementation promotes greater DMI, and hence, ADG of steers during the finishing feedlot phase. The basis for this effect on feed intake is not certain, but is apparently independent of potential tannin effects on metabolizable protein supply. Source of supplemental tannin (condensed vs. hydralysable) have minimal effects on overall growth performance response to supplementation. Addition of rumen-protected methionine and lysine to conventional steam flaked corn-based diets may enhance gain efficiency and dietary energetics during the early growing phase (first 112 d). Within the range of 267 to 321 kg, weight at first implanting does not affect growth-performance or carcass characteristics. Interval growth performance of implanted and non-implanted calf-fed Holsteins is a predictable function of live weight. Implanting calf-fed Holsteins with a longer-duration implant on arrival followed by a combination implant on d 224 may result In slightly lower ADG than implanting with a combination implant at 112-d intervals. At a 20 mg/kg (DM basis) level of supplementation, Zn source does not affect growth performance of calf-fed Holstein steers. Increasing level of Zn supplementation (as ZnS04) from 20 to 40 mg/kg will not further enhance overall performance responses. Reducing the non-structural carbohydrate concentration of a conventional steam-flaked corn-based growing finishing diet for Holstein steers can effectively enhance growth performance, particularly during the early growing and late finishing phases. Supplemental hydrolyzed yeast enhances ADG of Holstein steers throughout the growing-finishing period, resulting in marked increases in final carcass weight. This effect is due to consistent increases in DMI. Increasing DCAD of Holstein steers fed a conventional steam-flaked corn-based diet under conditions of high ambient temperature does not enhance growth performance or estimated dietary NE. Form of incorporation of minor dietary ingredients during batch mixing (dry premix or in combination with a llquid carrier) will not appreciably affect the feeding value of growing-finishing diets for Holstein steers. Partial replacement of flaked corn with extruded corn does not have beneficial effects on rumlnal microbial efficiency and digestive function. The feeding value of extruded corn for Holstein steers is comparable to that of steam flaked corn provided the inclusion rate does not exceed 20% of diet dry matter.Even when finishing diet formulations for Holstein steers exceed MP requirements, dietary UFP levels remain a relevant factor to optimize dietary energy use. Dietary UFP levels greater than 0.50% could negatively affect digestion, gain efficiency, and dietary NE use.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Ramos-Avina, D., A. Plascencia, and R.A. Zinn. 2018. Influence of dietary nonstructural carbohydrates concentration on growth performance and carcass characteristics of Holstein steers. A. J. Anim. Sci. 31 ?? 859-863
• Type: Journal Articles Status: Published Year Published: 2018 Citation: C.A. Pacheco, M. F. Montano, N. G. Torrentera, J. Salinas-Chavira, J. J. Ortiz. A. B. Cano, and R.A. Zinn. 2018. Influence of dietary cation-anion difference in finishing diets fed to Holstein steers during periods of high ambient temperature on feedlot performance and digestive function. J. Appl. Anim. Res. 46:729-733.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: J. Salinas-Chavira, M. F. Montano-Gomez, J. D. Navarrete, C. Raymundo, N. G. Torrentera, and R.A. Zinn. 2018. Influence of mixing supplements (dry or liquid) with monensin or soluble protein on the feeding value of finishing diets for feedlot cattle. J. Appl. Anim. Res. 46:734-739
• Type: Journal Articles Status: Published Year Published: 2018 Citation: Plascencia, A., M.F. Montano, J. Salinas-Chavira, N. Torrentera, and R.A. Zinn. 2018. Influence of supplemental tocopherol level (0, 250 and 500 IU RRR-a-tocopherol/d/steer) and injectable retinol form (retinyl propionate vs retinyl palmitate) on growth performance, carcass characteristics and plasma concentration in calf-fed Holstein steers. J. App. Anim. Res. 46:1516-1521
• Type: Journal Articles Status: Published Year Published: 2019 Citation: M.F. Montano, J. 0. Chirino, B. C. Latack, J. Salinas-Chavira, and R. A. Zinn. 2019. Influence of supplementation of growing diets enriched with ruminal protected methionine and lysine on feedlot performance and characteristics of digestion in Holstein steer calves. Applied Animal Science 35:318 -324.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: L.Buenabad, A.Y. Jacinto, A. Lopez, M. Montano, J. Salinas-Chavira, R.A. Zinn. 2019. Extruded corn meal as a partial replacement for steam flaked corn in finishing diets for feedlot cattle: growth performance and digestive function of feedlot cattle. Open Journal of Animal Sciences, 2019, 9, 196-206.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: J.Salinas-Chavira, G. Lopez-Valencia, M. Montano, A. Plascencia, and R. A. Zinn. 2019. Influence of urea fermentation potential on growth performance, dietary energetics, digestive function, and blood urea N in Holstein steers fed a finishing diet based on steam-flaked corn where metabolizable protein supply was otherwise in excess of theoretical requirements. Appl. Anim. Sci. 35:388-397.

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:Animal nutritionists, feedlot cattle industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Journal publications and presentations at conferences. What do you plan to do during the next reporting period to accomplish the goals?Further evaluate ruminally protected metabolozable amino acid sources in balancing diet formulations that otherwise meet metabolizable protein requirements during the initial 112 d on growth performance, efficiency of energy utilization and characteristics of digestion and metabolizable amino acid supply.

Impacts
What was accomplished under these goals? Influence of dietary nonstructural carbohydrates concentration on growth performance and carcass characteristics of Holstein steers was evaluated. Sixty Holstein steer calves (129±2.2 kg) were blocked by initial weight into five groups and randomly assigned within weight groupings to 10 pens. Calves were fed with a steam-flaked corn-based finishing diets containing 51% higher fiber (HF) or 64% lower fiber (LF) nonstructural carbohydrates. Non-structural carbohydrates concentrations were manipulated substituting dried distiller grain with solubles and alfalfa hay for flaked corn. Study shows that reducing the non-structural carbohydrate concentration of a conventional steam-flaked corn-based growing finishing diet for Holstein steers can effectively enhance growth performance, particularly during the early growing and late finishing phases. Influence of dietary cation -anion difference (DCAD) on growth performance and carcass characteristics was evaluated in 126 Holstein steers (457.1±27.5 kg BW). Treatments consisted of steam-flaked corn-based diets supplemented to provide DCAD of 34, 84 or 134 mEq/kg diet DM. Six Holstein steers (196±3 kg) with cannulas in rumen and proximal duodenum were used in a replicated 3×3 Latin Square design to evaluated treatment effects on digestion characteristics. Study showed that increasing DCAD of Holstein steers fed a conventional steam-flaked corn-based diet under conditions of high ambient temperature willnot enhance growth performance. The influence of supplement form (dry vs liquid) on the feeding value of complete mixed diets for feedlot cattle was evaluated. Four dietary treatments were compared: 1) dry supplement (DS, all supplemental macro- and micro-minerals, salt, monensin, and urea added to complete mixed diet as a dry premix); 2) liquid supplement (LS, all supplemental macro- and micro-minerals, salt, monensin and urea provided as a uniform blend with cane molasses; 3) LS minus monensin, that was provided in a 3% premix with dried distillers grains plus solubles before combination into a complete mixed diet (LS-MON, and 4) LS, except that condensed molasses solubles replaced 41% (DM basis) of the cane molasses solids (LSUF). Treatment effects on growth performance was evaluated in a 112-d trial involving 160 Holstein steers (473 ± 32 kg). Study shows that the form of incorporation of minor dietary ingredients during batch mixing (dry premix or in combination with a liquid carrier) will not appreciably affect the feeding value of growing-finishing diets for feedlot cattle.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Ramos-Avina, D., A. Plascencia, and R.A. Zinn. 2018. Influence of dietary nonstructural carbohydrates concentration on growth performance and carcass characteristics of Holstein steers. A. J. Anim. Sci. 31: 859-863.
• Type: Journal Articles Status: Published Year Published: 2017 Citation: C.A. Pacheco, M.F. Montano, N.G. Torrentera, J. Salinas-Chavira, J.J. Ortiz, A.B. Cano, and R.A. Zinn. 2018. Influence of dietary cation-anion difference in finishing diets fed to Holstein steers during periods of high ambient temperature on feedlot performance and digestive function. J. Appl. Anim. Res. 46:729-733.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: J. Salinas-Chavira, M. F. Montano-Gomez, J. D. Navarrete, C. Raymundo, N. G. Torrentera, and R.A. Zinn. 2018. Influence of mixing supplements (dry or liquid) with monensin or soluble protein on the feeding value of finishing diets for feedlot cattle. J. Appl. Anim. Res. 46:734-739

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:Animal nutritionists, feedlot cattle industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Journal publications and presentations at conferences. What do you plan to do during the next reporting period to accomplish the goals?Evaluate implant strategies to optimize growth performance of calf-fed Holsteins taken to heavier final harvest weights. Evaluated pen space requirements for optimal growth performance of Holstein steers during the late growing and finishing phase. Further evaluate practical metabolizable amino acid sources in balancing diet formulations to meet amino acid requirements during the initial 112 d on growth performance, efficiency of energy utilization and characteristics of digestion. Examine the relationship among surface-skin temperature, body core temperature, respiration rate, physiological status, and the behavior of Holstein steers under heat stress and different feeding management. Evaluate calcium requirements of calf-fed Holstein steers (initial weight 130 kg) during the initial 112-d growing phase.Evaluate the influence of virginiamycin supplementation during the late growing and finishing phase on growth performance, liver abscess, and carcass characteristics of calf-fed Holstein steers.

Impacts
What was accomplished under these goals? One hundred sixty-eight steer calves (133 ± 7 kg) were used in the 336-d growth-performance study. Treatments consisted of steam-flaked corn-based diet supplemented with (DM basis): 1) 20 mg/kg Zn as ZnSO4; 2) 10 mg/kg Zn as ZnSO4 plus 10 mg/kg Zn as Zn betaine; 3) 20 mg/kg Zn as Zn betaine; and 4) 40 mg/kg Zn as ZnSO4. Study shows that at a 20 mg/kg (DM basis) level of supplementation, Zn source does not affect growth-performance of calf-fed Holstein steers. Increasing level of Zn supplementation from 20 to 40 mg/kg will not further enhance overall performance responses. Two trials were conducted to examine the effects of level of supplemental methionine. Dietary treatments consisted of a steam-flaked corn-based diet containing urea as the only source of supplemental nitrogen supplemented with: 1) no amino acid supplementation; 2) 0.032% methionine plus 1.01% lysine; 3) 0.064% methionine plus 1.01% lysine; 4) 0.096% methionine plus 1.01% lysine; and 5) 0.128% methionine plus 1.01% lysine. In Trial 1, 150 Holstein steer calves (127± 4.9 kg) were utilized to evaluate the influence of treatments on growth-performance, dietary energetic, plasma amino acid concentration during the first112 days of growing period. In Trial 2, 5 Holstein steers with cannulas in the rumen and proximal duodenum were used to evaluate treatment effects on characteristics of digestion and amino acid supply to the small intestine. Study shows that addition of rumen-protected methionine and lysine to diets may enhance gain efficiency and dietary energetics of growing Holstein calves. Observed amino acid supply to the small intestine were in good agreement with expected, supportive of NRC (2000, Level 1). One hundred sixty-eight crossbred steers (133 ± 7 kg) were used in a 336-d experiment to evaluate the effects of enzymatically hydrolyzed yeast cell wall plus yeast culture (EHY) supplementation on growth performance and carcass characteristics. Treatments consisted of steam-flaked corn-based diet supplemented with 0, 195, 390 or 585 mg/kg EHY. Study shows that throughout the growing-finishing period, supplemental EHY will enhance ADG, resulting in marked increases in final carcass weight. This effect is due to consistent increases in DMI, as supplementation did not affect gain efficiency or estimated dietary NE.

Publications

• Type: Journal Articles Status: Published Year Published: 2017 Citation: M.F. Montano, A. Plascencia, J. Salinas-Chavira, N. Torrentera, and R.A. Zinn. 2017. Influence of level and form of supplemental zinc on feedlot growth performance and carcass characteristics of calf-fed Holstein steers. Prof. Anim. Sci. 33:651-658.
• Type: Journal Articles Status: Published Year Published: 2017 Citation: N. Torrentera, R. Carrasco, J. Salinas-Chavira, A. Plascencia, and R. A. Zinn. 2017. Influence of methionine supplementation of growing diets enriched with lysine on feedlot performance and characteristics of digestion in Holstein steer calves. Asian-Australas J Anim. Sci. 30:42-50.
• Type: Journal Articles Status: Published Year Published: 2018 Citation: J. Salinas-Chavira, M.F. Montano, N. Torentera, and R.A. Zinn. 2018. Influence of feeding enzymatically hydrolysed yeast cell wall?+?yeast culture on growth performance of calf-fed Holstein steers. J. Appl. Anim. Res. 30: https://doi.org/10.1080/09712119.2017.1299742

Progress 10/01/15 to 09/30/16

Outputs
Target Audience:Animal nutritionists, feedlot cattle industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Journal publications and presentations at conferences. What do you plan to do during the next reporting period to accomplish the goals?Evaluate zinc requirements of calf-fed Holsteins over the entire 312-d feeding period. Evaluate implant strategies to optimize growth performance of calf-fed Holsteins taken to heavier final harvest weights. Further evaluate practical metabolizable amino acid sources in balancing diet formulations to meet amino acid requirements during the initial 112 d on growth performance, efficiency of energy utilization and characteristics of digestion. Compare the impact of four implant management scenarios growth-performance, carcass characteristics, and net energy utilization of calf-fed Holstein steers. Examine the relationship among surface-skin temperature, body core temperature, respiration rate, physiological status, and the behavior of Holstein steers under heat stress and different feeding management.

Impacts
What was accomplished under these goals? Fifty Holstein steers calves (121 kg) were used to evaluate effects of route of administration of vitamin E at time of arrival on plasma tocopherol during in the initial 16 d following arrival. Plasma tocopherol was not different for intramuscular vs subcutaneous routes of administration. Subcutaneous administration is a practical alternative to conventional intramuscular administration of injectable vitamin E. Two experiments were conducted to examine the influence of protein and virginiamycin (VM) supplementation on feedlot growth performance, digestion, and metabolizable AA (MAA) supply of calf-fed Holstein steers. Growth performance and dietary energetics were evaluated in 120 Holstein steers (127 kg). Characteristics of digestion were evaluated using 4 Holstein steers (146 kg) with cannulas in the rumen and proximal duodenum. Study reveals that enhancements in energy utilization when diets are balanced to meet MAA requirements of calf-fed Holstein steers during the initial 112-d feedlot period remain appreciable throughout time on feed. Virginiamycin enhanced efficiency of energy utilization throughout the 308-d feedlot growing-finishing period. Two experiments were conducted to examine the influence of kaolinite clay supplementation (0%, 1%, or 2% diet dry matter [DM] basis) on characteristics of digestion (Trial 1) and growth performance (Trial 2) in calf-fed Holstein steers. Study reveals that kaolinite supplementation up to 2% of diet DM may enhance energetic efficiency of calf-fed Holstein steers in a manner independent of changes in characteristics of ruminal and total tract digestion.

Publications

• Type: Journal Articles Status: Published Year Published: 2016 Citation: A. Plascencia, E. G. Alverez, and R. A. Zinn. 2016. A comparison of via of administration of injection of vitamin E in newly received feedlot calves. Nova Scientia 7: 11-18
• Type: Journal Articles Status: Published Year Published: 2016 Citation: J. Ortiz, M. Monta�o, A. Plascencia, J. Salinas, N. Torrentera and R. A. Zinn. 2016. Influence of Kaolinite Clay Supplementation on Growth Performance and Digestive Function in Finishing Calf-fed Holstein Steers. A. J. Anim. Sci. �29: 1569 -1575.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: J. Salinas-Chavira, A. Barreras, A. Plascencia, M. F. Montano, J. D. Navarrete, N. Torrentera, and R. A. Zinn. 2016. Influence of protein nutrition and virginiamycin supplementation on feedlot growth performance and digestive function of calf-fed Holstein steers. J. Anim. Sci. 94:4276 -4286.

Progress 01/29/15 to 09/30/15

Outputs
Target Audience:Animal nutritionists, feedlot cattle industry. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Nothing Reported How have the results been disseminated to communities of interest?Journal publications and presentations at conferences. What do you plan to do during the next reporting period to accomplish the goals?Evaluate zinc requirements of calf-fed Holsteins over the entire 312-d feeding period. Evaluate implant strategies to optimize growth performance of calf-fed Holsteins taken to heavier final harvest weights. Evaluate prebiotic supplementation on health and growth-performance of calf-fed Holstein steers.

Impacts
What was accomplished under these goals? Current work reveals the both gain and efficiency of gain of calf-fed Holstein steers during the initial 112 d on feed (first third of the overall feeding period) is limited by metabolizable amino acid supply. During this period calves attempt to compensate for the deficiency of metabolizable amino by increasing feed intake. The accommodation results in marked decrease in efficiency of utilization dietary NE. Supplementation with one or two ruminally protected amino acids (ie methionine and lysine) may not be adequate to overcome the limitation in conventional growth-finishing diets. The loss in growth efficiency is not compensated for during the subsequent 224 d on feed. Preliminary results show that supplemental virginiamycin reduces core body temperature of Holsteins steers, an important consideration during periods of high ambient temperature.

Publications

• Type: Journal Articles Status: Published Year Published: 2015 Citation: Alejandro Plascencia-Jorquera, Enrique Gilberto Alvarez-Almora and Richard Zinn. 2015. A comparison of via of administration of the injection of vitamin E in newly received feedlot calves. Nova Scientia 7: 11-18. B.H. Gutierrez, E. Alvarez, A.A. Arrizon, R. Carrasco, J. Salinas-Chavira & R.A. Zinn. 2016. Influence of high-oil algae biomass as a feed intake and growth-performance enhancer in feedlot cattle during period of high ambient temperature, J. Appl. Anim. Res. 44:118-120 J. A. Aguilar-Hern�ndez J. D. Ur�as-Estrada, M. A. L�pez-Soto, A. Barreras, A. Plascencia, M. Monta�o, V. M. Gonz�lez-Vizcarra, A. Estrada-Angulo, B. I. Castro-P�rez, R. Barajas, H. I. Rogge, and R. A. Zinn. 2016. Evaluation of isoquinoline alkaloid supplementation levels on ruminal fermentation, characteristics of digestion, and microbial protein synthesis in steers fed a high-energy diet. J. Anim. Sci. 94:267-274.