Animal Sciences Commons^™

Rumen Bacterial Community Structure Impacts Feed Efficiency In Beef Cattle, Henry A. Paz, Kristin E. Hales, James E. Wells, Larry A. Kuehn, Harvey C. Freetly, Elaine D. Berry, Michael D. Flythe, Matthew L. Spangler, Samodha C. Fernando

Department of Animal Science: Faculty Publications

The importance of the rumen microbiota on nutrient cycling to the animal is well recognized; however, our understanding of the influence of the rumen microbiome composition on feed efficiency is limited. The rumen microbiomes of two large animal cohorts (125 heifers and 122 steers) were characterized to identify specific bacterial members (operational taxonomic units [OTUs]) associated with feed efficiency traits (ADFI, ADG, and G:F) in beef cattle. The heifer and steer cohorts were fed a forage-based diet and a concentrate-based diet, respectively. A rumen sample was obtained from each animal via esophageal tubing and bacterial community composition was …

Expression Of Cytokine Genes And Receptors In White Blood Cells Associated With Divergent Body Weight Gain In Beef Steers, Amanda K. Lindholm-Perry, Virginia M. Cederberg, Jeremy R. Miles, Andrew P. Foote

Department of Animal Science: Faculty Publications

Previous work examining the transcriptome of steer tissue samples from animals with divergent gain have shown a relationship with the expression of genes with functions in immune and inflammatory pathways. The process of mounting an immune or inflammatory response is energetically expensive and variation in cytokine responses may affect cattle production traits. In addition, a previous study has identified variation in the transcript abundance of numerous genes, including the cytokine gene IL6ST, in the circulating white blood cells of pigs associated with high and low residual feed intake (RFI) lines. The aim of this study was to determine whether …

Qtls Associated With Dry Matter Intake, Metabolic Mid-Test Weight, Growth And Feed Efficiency Have Little Overlap Across 4 Beef Cattle Studies, Mahdi Saatchi, Jonathan E. Beever, Jared E. Decker, Dan B. Faulkner, Harvey C. Freetly, Stephanie L. Hansen, Helen Yampara-Iquise, Kristen A. Johnson, Stephen D. Kachman, Monty S. Kerley, Jaewoo Kim, Daniel D. Loy, Elisa Marques, Holly L. Neibergs, E. John Pollak, Robert D. Schnabel, Christopher M. Seabury, Daniel W. Shike, W. M. Snelling, Matthew L. Spangler, Robert L. Weaber, D. J. Garrick, Jeremy F. Taylor

Department of Animal Science: Faculty Publications

Background: The identification of genetic markers associated with complex traits that are expensive to record such as feed intake or feed efficiency would allow these traits to be included in selection programs. To identify large-effect QTL, we performed a series of genome-wide association studies and functional analyses using 50 K and 770 K SNP genotypes scored in 5,133 animals from 4 independent beef cattle populations (Cycle VII, Angus, Hereford and Simmental × Angus) with phenotypes for average daily gain, dry matter intake, metabolic mid-test body weight and residual feed intake.

Results: A total of 5, 6, 11 and 10 significant …

Influence Of Corn Hybrid Traits On Digestibility And The Efficiency Of Gain In Feedlot Cattle, S. L. Jaeger, Matt K. Luebbe, C. N. Macken, Galen E. Erickson, Terry J. Klopfenstein, W. A. Fithian, David S. Jackson

Department of Animal Science: Faculty Publications

Two experiments were conducted to determine the influence of chemical and physical corn kernel traits on digestibility and feedlot cattle performance. Seven commercially available corn hybrids representing a range in kernel traits were evaluated for a variety of chemical and physical traits that included test weight, 1,000-grain weight, kernel size, starch, CP, amylose, Stenvert Hardness tests (kernel hardness traits), tangential abrasive dehulling device loss, 12-h in vitro starch disappearance, and rate and extent of in situ DM disappearance. Differences among hybrids existed for all physical kernel traits measured. In Exp. 1, 224 steers in 28 pens were fed the same …