Research Project: Optimizing Nutrient Management and Efficiency of Beef Cattle and Swine

Location: Nutrition, Growth and Physiology

2023 Annual Report

Objectives
Objective 1. Targeted nutrient delivery to improve efficiency of growth and to meet requirements for pregnancy and lactation. Objective 2. Determine dynamic changes in nutrient requirements as the animal’s physiological status changes to allow for timed nutrient delivery. Objective 3. Determine metabolic and physiological mechanisms responsible for variation in feed efficiency that are under genetic and epigenetic control. Objective 4: Evaluate the lifetime production of GHG from ruminant animal systems (cattle and/or sheep) in controlled and rangeland settings, incorporating nutritional, production management, and health factors as they contribute to variation in emissions.

Approach
Feed costs represent the single largest input in both beef and swine production; however, less than 20% of the energy from feed is converted to edible product. Improving the efficiency that feed is converted to animal products has the potential to improve the economic efficiency of animal production while also improving the sustainability of animal agriculture. Variation in the utilization of nutrients for maintenance, gain, reproduction, and lactation are functions of the ability of livestock at various physiological stages to convert the nutrients in feed to meat products and to maximize lifetime productivity. The objectives in this project plan address critical components that contribute to variation in nutrient utilization and feed efficiency at multiple physiological stages from fetal development to mature animals. Traditionally, research has been conducted within discipline. A robust approach encompassing a combination of genomics, physiology, epigenetics, management, and classical nutrition needs to be used to understand and improve feed efficiency. Growth and feed efficiency are influenced by management strategies, diet, metabolism, physiology, and genetic potential. A comparative biology approach for beef cattle and swine utilizing systems research methodologies will be used to identify molecular, physiological, biological pathways, and mechanisms responsible for nutrient utilization and feed efficiency in both species.

Progress Report
Twenty cannulated beef steers were fed low protein diets containing either supplemental rumen protected lysine, methionine, or a combination of methionine and lysine, and compared to a basal without these added amino acids, or a diet with adequate protein from traditional sources. Samples were collected to allow for evaluation of any changes on amino acid flow to the small intestine, as well as overall changes to intake, nutrient digestibility, and nitrogen balance. (Objective 1) One hundred-sixty beef steers were fed the same set of diets and evaluated for changes in intake, average daily gain, feed efficiency, and any potential changes to plasma amino acid concentrations. (Objective 1) Sixteen cannulated beef steers were utilized in an experiment to evaluate the impacts of frequency of rumen protected lysine supplementation on intake, nutrient digestibility, and nitrogen balance. (Objective 1) Two studies were conducted to evaluate protein source and roughage inclusion in feedlot steers fit with rumen and duodenal cannulas. Data from this study will determine whether protein source or roughage inclusion rates alter intake, nutrient digestibility, and amino acid flow to the small intestine. (Objective 1) Feed intake and protein concentrations of the diet were evaluated utilizing 15 steers fit with rumen and duodenal cannulas. Factors evaluated included amino acid flow from the rumen and changes to nutrient digestibility. (Objective 1) Forty bulls were developed at two different rates of gain (1.13 kg/d or 1.8 kg/d) for 112 days leading up to the breeding season. Of these, six from each treatment were selected and turned out with 250 heifers for a 29-day breeding season, of which half were allowed to consume 0.91 kg/d of a commercial range cube. One hundred fifty-one calves were born from the 250 exposed heifers. Bull fertility measurements as well as heifer fertility and calf growth measurements were taken. (Objective 2) One hundred and twenty steers were placed on a feed efficiency study and monitored for individual feed intake and weight gain. Nine of the most and nine least feed efficient animals were selected for an immune challenge to evaluate differences in hematology parameters, cytokine and acute phase protein elevation, and whole blood transcriptome profiles. (Objective 3) Body condition scores (BCS) on over 3,000 mature cows were obtained and cows with BCS = 4 were selected for sampling. Blood and a hair samples from the hip were collected from low BCS animals and a control animal matched for age, breed and barn. (Objective 3) Feed efficiency phenotypes have been obtained for 20 feed efficiency studies performed between 2007-2019. Animals with high gain, low intake phenotypes and those with low gain, high intake phenotypes have been selected for further study, which will include low pass sequencing and targeted genotyping. (Objective 3) Twenty-eight pubertal heifers were utilized to assess the influence of an isoenergetic diet derived from divergent energy sources (either concentrate- or forage-based). Circulating concentrations of metabolites/hormones, measures of body composition, estrus/rumination behavior, and response to a dextrose infusion challenge were assessed for the establishment of the metabolic profile by dietary treatment, then parameters of blood-brain barrier structure and neuropeptide expression will be evaluated. (Objective 3) One hundred yearling steers are being individually fed in a Calan Gate feeding system to determine feed efficiency over a 63-day feeding period. Circulating concentrations of metabolites/hormones and measures of body composition will be assessed. Following the feeding period, a population of steers that represent animals consuming divergent amounts of feed, but gaining the same rate of body weight gain will be harvested for collection of hypothalamic tissue. Hypothalamic tissue will be analyzed for structural properties of the blood-brain barrier and neuropeptide expression by feed efficiency classification. (Objective 3) Two hundred and forty heifers were fed one of four treatments through the periconceptual period of pregnancy to determine whether methyl donor availability to the heifers affected calf growth. Eighty-two qualifying calves were born from the study and will continue to take measurements on the calves through finishing. (Objective 3)

Accomplishments
1. Prenatal vitamins are important for beef cattle to support embryonic development. The inclusion of methionine, choline, folate, and vitamin B12, which are all compounds found in human prenatal vitamins, to beef cattle feeding and management protocols prior to pregnancy is a novel concept. ARS scientists at Clay Center, Nebraska, in collaboration with researchers at North Dakota State University, studied the effectiveness of vitamin supplementation and identified the ideal feeding doses of methionine and choline, and injection doses of folate and Vitamin B12 in beef heifers. The manufacturer’s recommended feed inclusion levels of methionine and choline, and administration of vitamin B12 and folate at 20 mg and 320 mg once per week, respectively, were the optimal dosages to increase the circulating concentration of these prenatal vitamins to improve embryonic development. Supplementing these compounds during early pregnancy provides beef producers with an opportunity to improve fetal growth and calf performance, and improve whole herd production efficiencies.

2. Mature cow feed consumption is a heritable trait. Sixty to seventy percent of feed intake is used to maintain basic body function in beef cows. ARS scientists at Clay Center, Nebraska, determined the amount of feed needed for maintenance is variable across cows by as much as two times and that body maintenance requirement is a moderately heritable trait (0.31). This study suggest cows could be genetically selected for reduced feed consumption without compromising pounds of calf weaned to improve efficiency of beef production and producer profitability.

3. Novel method for detecting gene expression important for beef cattle feed efficiency. The cost of evaluating all genes expressed in a tissue has typically resulted in studies with small numbers of animals. ARS scientists at Clay Center, Nebraska, have shown that a meta-analysis approach can be used to combine data from multiple independent studies. This method increases the number of animals sampled, reduces the breed, environment, diet, or management bias of each study, and increases both statistical power and robustness of the results. This is a novel approach to livestock studies that leverages and expands current studies of feed efficiency and allows us to identify genes involved in feed efficiency regardless of the genetics, environment, or management of the populations of beef cattle included. The identification of mechanisms underlying feed efficiency in beef cattle will provide strategies to improve animal performance across multiple breeds and populations.

4. Heifer undernutrition is not rescued by vitamin/mineral supplementation. The vitamin and mineral requirements of young female cattle (heifers) during early gestation is an area that has been overlooked in research because cattle are fed at levels for maintenance, even during pregnancy. Only approximately 50% of producers provide a complete mineral or trace mineral salt to their cows during the spring/summer when most cows are pregnant. ARS scientists at Clay Center, Nebraska, and investigators at North Dakota State University, tested whether heifers fed standard or restricted diets that were either supplemented or not supplemented with vitamins and minerals during early pregnancy affected the fetus. Results showed that undernutrition in heifers negatively programmed liver metabolism in the fetus towards a starved state which can lead to high weight gain, metabolic issues, and infertility. While vitamin and mineral supplementation is important for heifers during pregnancy, it is not enough to counter the issues related to fetal development due to dam undernutrition. These data stress the importance of producer management of heifer nutrition during early pregnancy to reduce detrimental effects on fetal performance.

Review Publications
Rathert-Williams, A.R., McConnell, H.L., Salisbury, C.M., Lindholm-Perry, A.K., Lalman, D.L., Pezeshki, A., Foote, A.P. 2023. Effects of adding ruminal propionate on dry matter intake and glucose metabolism in steers fed a finishing ration. Journal of Animal Science. 101. Article skad072. https://doi.org/10.1093/jas/skad072.
Reynolds, L.P., Diniz, W.J., Crouse, M.S., Caton, J.S., Dahlen, C.R., Borowicz, P.P., Ward, A.K. 2022. Maternal nutrition and developmental programming of offspring. Reproduction, Fertility and Development. 35(2):19-26. https://doi.org/10.1071/RD22234.
Crouse, M.S., Freetly, H.C., Lindholm-Perry, A.K., Neville, B.W., Oliver, W.T., Lee, R.T., Syring, J.G., King, L.E., Reynolds, L.P., Dahlen, C.R., Caton, J.S., Ward, A.K., Cushman, R.A. 2023. One-carbon metabolite supplementation to heifers for the first 14 d of the estrous cycle alters the plasma and hepatic one-carbon metabolite pool and methionine-folate cycle enzyme transcript abundance in a dose-dependent manner. Journal of Animal Science. 101. Article skac419. https://doi.org/10.1093/jas/skac419.
Prezotto, L.D., Thorson, J.F. 2023. Effect of dietary urea in gestating beef cows: Circulating metabolites, morphometrics, and mammary secretions. Animals. 13(1). Article 6. https://doi.org/10.3390/ani13010006.
Menezes, A.B., Dahlen, C.R., McCarthy, K.L., Kassetas, C.J., Baumgaertner, F., Kirsch, J.D., Dorsam, S.T., Neville, T.L., Ward, A.K., Borowicz, P.P., Reynolds, L.P., Sedivec, K.K., Forcherio, J.C., Scott, R., Caton, J.S., Crouse, M.S. 2023. Fetal hepatic lipidome is more greatly affected by maternal rate of gain compared with vitamin and mineral supplementation at day 83 of gestation. Metabolites. 13(2). Article 175. https://doi.org/10.3390/metabo13020175.
Chakrabarty, S., Serum, E.M., Winders, T.M., Neville, B.W., Kleinhenz, M.D., Magnin, G., Coetzee, J.F., Dahlen, C.R., Swanson, K.C., Smith, D.J. 2022. Rapid quantification of cannabinoids in beef tissues and bodily fluids using direct-delivery electrospray ionization mass spectrometry. Food Additives & Contaminants. https://doi.org/10.1080/19440049.2022.2107711.
Crouse, M.S., McCarthy, K.L., Menezes, A.C.B., Kassetas, C.J., Baumgaertner, F., Kirsch, J.D., Dorsam, S., Neville, T.L., Ward, A.K., Borowicz, P.P., Reynolds, L.P., Sedivec, K.K., Forcherio, J.C., Scott, R., Caton, J.S., Dahlen, C.R. 2022. Vitamin and mineral supplementation and rate of weight gain during the first trimester of gestation in beef heifers alters the fetal liver amino acid, carbohydrate, and energy profile at day 83 of gestation. Metabolites. 12. Article 696. https://doi.org/10.3390/metabo12080696.
Smith, D.J., Serum, E.M., Winders, T.M., Neville, B.W., Herges, G.R., Dahlen, C.R., Swanson, K.C. 2023. Excretion and residue depletion of cannabinoids in beef cattle fed hempseed cake for 111 days. Food Additives & Contaminants. 40(4):552-565. https://doi.org/10.1080/19440049.2023.2187645.
Eisemann, J.H., Nienaber, J.A., Huntington, G.B. 2022. Ractopamine and age alter oxygen use and nitrogen metabolism in tissues of beef steers. Journal of Animal Science. 100(11). Article skac304. https://doi.org/10.1093/jas/skac304.
Snider, A.P., Yake, H.K., Granger, C.D., Rosasco, S.L., McDaneld, T.G., Snelling, W.M., Chase Jr., C.C., Miles, J.R., Lents, C.A., Quail, L.K., Rich, J.J., Epperson, K.M., Crouse, M.S., Summers, A.F., Perry, G.A., Bennett, G.L., Cushman, R.A. 2023. Polymorphism of the follicle stimulating hormone receptor does not impact reproductive performance or in-vitro embryo production in beef heifers. Theriogenology. 195:131-137. https://doi.org/10.1016/j.theriogenology.2022.10.025.
Keel, B.N., Lindholm-Perry, A.K. 2022. Recent developments and future directions in meta-analysis of differential gene expression in livestock RNA-Seq. Frontiers in Genetics. 13. Article 983043. https://doi.org/10.3389/fgene.2022.983043.
Syring, J.G., Crouse, M.S., Neville, T.L., Ward, A.K., Dahlen, C.R., Reynolds, L.P., Borowicz, P.P., McLean, K.J., Neville, B.W., Caton, J.S. 2023. Concentrations of vitamin B12 and folate in maternal serum and fetal fluids, metabolite interrelationships, and hepatic transcript abundance of key folate and methionine cycle genes: The impacts of maternal nutrition during the first 50 d of gestation. Journal of Animal Science. 101(1). Article skad139. https://doi.org/10.1093/jas/skad139.
Snider, A.P., McCarthy, K.L., Wright-Johnson, E.C., Ondrak, J.D., Oliver, W.T., Dahlen, C.R., Cushman, R.A., Crouse, M.S. 2022. Yearling bulls have reduced sperm concentration and increased seminal plasma interleukin-8 after a 28-day breeding season. Reproduction of Domestic Animals. 57:1465-1473. https://doi.org/10.1111/rda.14223.
Tanner, A.R., Bauer, M.L., Swanson, K.C., Kennedy, V.C., Kirsch, J.D., Gaspers, J., Negrin-Pereira, N., Fontoura, A.B.P., Perry, G.A., Stokka, G., Rodas-Gonzales, A., Ward, A., Dahlen, C.R., Neville, B., Borowicz, P.P., Reynolds, L.P., Ominski, K.H., Vonnahme, K.A. 2023. Influence of corn supplementation to beef cows during mid- to late-gestation: Supplementation decreases placental microvascular surface density but does not alter uterine blood flow or neonatal performance. Livestock Science. 268. Article 105155. https://doi.org/10.1016/j.livsci.2023.105155.
Winders, T.M., Serum, E.M., Smith, D.J., Neville, B.W., Mia, G.K., Amat, S., Dahlen, C.R., Swanson, K.C. 2022. Influence of hempseed cake inclusion on growth performance, carcass characteristics, feeding behavior, and blood parameters in finishing heifers. Journal of Animal Science. 100:1-8. https://doi.org/10.1093/jas/skac159.
Webb, E.M., Holman, D.B., Schmidt, K.N., Crouse, M.S., Dahlen, C.R., Cushman, R.A., Snider, A.P., McCarthy, K.L., Amat, S. 2023. A longitudinal characterization of the seminal microbiota and antibiotic resistance in yearling beef bulls subjected to different rates of gain. Microbiology Spectrum. 11(2). Article e05180-22. https://doi.org/10.1128/spectrum.05180-22.
Freetly, H.C., Jacobs, D.R., Thallman, R.M., Snelling, W.M., Kuehn, L.A. 2023. Heritability of beef cow metabolizable energy for maintenance. Journal of Animal Science. 101. Article skad145. https://doi.org/10.1093/jas/skad145.
Sanglard, L.P., Snelling, W.M., Kuehn, L.A., Thallman, R.M., Freetly, H.C., Wheeler, T.L., Shackelford, S.D., King, D.A., Spangler, M.L. 2022. Genetic and phenotypic associations of mitochondrial DNA copy number, SNP, and haplogroups with growth and carcass traits in beef cattle. Journal of Animal Science. 101. Article skac415. https://doi.org/10.1093/jas/skac415.