Meat Science Commons^™

Microbial Community Structure From Southern High Plains Beef Cattle Feedyard Manure And Relationship With Nitrous Oxide Emissions, Heidi Waldrip, David Parker, Sierra Miller, Lisa M. Durso, Byeng R. Min, Daniel N. Miller, Kenneth Casey, Bryan Woodbury, Mindy J. Spiehs

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Modern molecular techniques enable characterization of the microbial biome in livestock manure, from which there is particular concern over emission of greenhouse gases. This study evaluated how sampling depth, time, temperature, and artificial rainfall affected microbial community structure in feedyard manure, and relationships between the manure biome and known parameters related to nitrous oxide (N₂O) emissions. In three large incubation chambers, maintained at different temperatures that received two applications of artificial rainfall, we evaluated manure microbiome composition and abundance of N₂O-producing enzymes (nirK and nirS) using quantitative polymerase chain reaction (qPCR). These data were …

Evaluating The Shelf Life And Sensory Properties Of Beef Steaks From Cattle Raised On Different Grass Feeding Systems In The Western United States, Toni L. Duarte, Bakytzhan Bolkenov, Sarah C. Klopatek, James W. Oltjen, D. Andy King, Steven D. Shackelford, Tommy L. Wheeler, Xiang Yang

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Consumer interest in grass-fed beef has been steadily rising due to consumer perception of its potential benefits. This interest has led to a growing demand for niche market beef, particularly in the western United States. Therefore, the objective of this study was to assess the impact of feeding systems on the change in microbial counts, color, and lipid oxidation of steaks during retail display, and on their sensory attributes. The systems included: conventional grain-fed (CON), 20 months-grass-fed (20GF), 25-months-grass-fed (25GF) and 20-months-grass-fed + 45-day-grain-fed (45GR). The results indicate that steaks in the 20GF group displayed a darker lean and fat …

Genes Involved In Feed Efficiency Identified In A Meta-Analysis Of Rumen Tissue From Two Populations Of Beef Steers, Amanda K. Lindholm-Perry, Allison M. Meyer, Rebecca J. Kern-Lunbery, Hannah C. Cunningham-Hollinger, Taran H. Funk, Brittney N. Keel

Roman L. Hruska U.S. Meat Animal Research Center: Reports

In cattle, the rumen is an important site for the absorption of feed by-products released by bacterial fermentation, and variation in ruminal function plays a role in cattle feed efficiency. Studies evaluating gene expression in the rumen tissue have been performed prior to this. However, validating the expression of genes identified in additional cattle populations has been challenging. The purpose of this study was to perform a meta-analysis of the ruminal transcriptome of two unrelated populations of animals to identify genes that are involved in feed efficiency across populations. RNAseq data from animals with high and low residual feed intake …

Prenatal Transportation Stress Did Not Impact Ovarian Follicle Count For Three Generations Of Female Brahman Offspring, Lacey K. Quail, Ronald D. Randel, Thomas H. Welsh Jr., Robert A. Cushman, Hannah K. Yake, Rui A. D'Orey Branco, Donald A. Neuendorff, Charles R. Long, George A. Perry

Roman L. Hruska U.S. Meat Animal Research Center: Reports

As prenatal transportation stress altered behavior and adrenal glucocorticoid secretion of calves, we hypothesized that prenatal transportation stress would decrease ovarian reserve size and negatively impact female offspring fertility. The impact of prenatal transportation stress on ovarian follicle numbers in female offspring for three generations was studied. Brahman cows were transported for 2 h on day 60 ± 5, 80 ± 5, 100 ± 5, 120 ± 5, and 140 ± 5 of gestation. Ovaries were collected from offspring of transported or non-transported dams at multiple ages. Primordial, primary, secondary, and antral follicles were histologically analyzed. Antral follicle numbers were …

Efficacy Of Antimicrobial Interventions Used In Meat Processing Plants Against Antimicrobial Tolerant Non–Antibiotic-Resistant And Antibiotic-Resistant Salmonella On Fresh Beef, Norasak Kalchayanand, Sapna Chitlapilly Dass, Yangjunna Zhang, Eric L. Oliver, Bing Wang, Tommy L. Wheeler

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Salmonella is a common cause of foodborne illness in the United States, and several strains of Salmonella have been identified as resistant to antibiotics. It is not known whether strains that are antibiotic resistant (ABR) and that have some tolerance to antimicrobial compounds are also able to resist the inactivation effects of antimicrobial interventions used in fresh meat processing. Sixty-eight Salmonella isolates (non-ABR and ABR strains) were treated with half concentrations of lactic acid (LA), peracetic acid (PAA), and cetylpyridinium chloride (CPC), which are used in beef processing plants to screen for tolerant strains. Six strains each from non-ABR and …

Effects Of Administration Of A Growth Promoting Implant During The Suckling Phase Or At Weaning On Growth, Reproduction, And Ovarian Development In Replacement Heifers Grazing Native Range, Shelby L. Rosasco, Emily A. Melchior-Tiffany, Cierrah J. Kassetas, Shad H. Cox, Richard L. Dunlap, Jennifer A. Hernandez Gifford, Eric J. Scholljegerdes, Robert A. Cushman, Adam F. Summers

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Management strategies utilized during pre-breeding development of replacement heifers can impact fertility and the ovarian reserve. Angus- Hereford crossbred heifers (n = 233) were utilized over a 3-yr period to determine the effects of administration of a growth promoting implant at either branding or weaning on growth, reproduction, and ovarian development. Heifer calves were randomly assigned to one of three treatments: 1) nonimplanted controls (CON; n = 79), 2) implanted at approximately 2 mo of age (average calf age = 58 d) with Synovex-C (BIMP, n = 82), or 3) implanted at approximately 7 mo of age (average calf …

Interaction Of Replacing Corn Silage With Soyhulls As A Roughage Source With Or Without 3% Added Wheat Straw In The Diet: Impacts On Intake, Digestibility, And Ruminal Fermentation In Steers Fed High-Concentrate Diets, Bryan W. Neville, Wayde J. Pickinpaugh, Lea J. Mittleider, Rebecca L. Moore, Kendall C. Swanson, Joel S. Caton

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Six ruminally cannulated steers [475.0 ± 49.6 kg initial body weight (BW)] were used in a 6 × 3 incomplete Latin square design (six treatments and three periods), to evaluate the impacts replacing of corn silage with pelleted soyhulls as roughage in high-concentrate finishing diets containing 30% modified distillers grains with solubles. Treatments were based on increasing dietary inclusion of soyhulls and consisted of: (1) Control (0), roughage supplied by dietary inclusion of 20% corn silage [dry matter (DM) basis]; (2) 50% replacement of corn silage with soyhulls (50); (3) 100% replacement of corn silage with soyhulls (100), and the …

Development And Validation Of High-Resolution Melting Assays For The Detection Of Potentially Virulent Strains Of Escherichia Coli O103 And O121, Frank J. Velez, Joseph M. Bosilevac, Sabine Delannoy, Patrick Fach, Ravinder Nagpal, Prashant Singh

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Virulent strains of Shiga toxin-producing Escherichia coli (STEC) serogroups O103 and O121 are considered adulterants in beef. Two high-resolution melting (HRM) real-time PCR assays were standardized for the specific detection and discrimination of potentially virulent and avirulent strains of E. coli O103 and O121. The O103 HRM assay offered the possibility to distinguish clearly STEC O103:H2 from STEC O103:H25. The two standardized assays were extensively validated using 215 pure culture strains, laboratory inoculated food samples, and naturally contaminated beef (n = 84) and pork (n = 84) enrichments collected from the red meat surveillance program. Both HRM assays showed 100% …

Impacts Of Added Roughage On Growth Performance, Digestibility, Ruminal Fermentation, And Ruminal Ph Of Feedlot Steers Fed Wheat-Based Feedlot Diets Containing 30% Modified Distillers Grains With Solubles, Wayde J. Pickinpaugh, Bryan W. Neville, Rebecca L. Moore, Joel S. Caton

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Two experiments were conducted to evaluate the inclusion rate roughage in wheat-based diets containing modified distillers grains with solubles (MDGS) on feedlot performance (Feedlot Experiment), as well as digestibility, ruminal pH, and ruminal fermentation characteristics (Digestibility Experiment). The feedlot experiment utilized 72 Angus steers (392 ± 46.3 kg initial body weight) which were randomly assigned to 1 of 12 pens, 3 pens per treatment, to evaluate feedlot performance and carcass characteristics. Dietary treatments were 1) control; 10% roughage, 2) 12% roughage, 3) 14% roughage, and 4) 16% roughage. The digestibility experiment used four ruminally and duodenally cannulated steers (393 ± …

Greater Numbers Of Antral Follicles In The Ovary Are Associated With Increased Concentrations Of Glucose In Uterine Luminal Fluid Of Beef Heifers, Alexandria P. Snider, Matthew S. Crouse, Shelby L. Rosasco, Kaitlin M. Epperson, Emmalee J. Northrop-Albrecht, Jerica J.J. Rich, Chadwick C. Chase Jr., Jeremy R. Miles, George A. Perry, Adam F. Summers, Robert A. Cushman

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Increased antral follicles are associated with greater fertility and a uterine environment that is more supportive of early embryonic development in beef heifers. Glucose is a primary energy source for embryos, and glucose concentrations are elevated in uterine luminal fluid (ULF) of pregnant heifers. We hypothesized that ULF glucose concentrations and endometrial transcript abundance for glucose transporters on d16 after insemination would be greater in heifers with increased numbers of antral follicles. Heifers classified with either increased or diminished antral follicle counts were artificially inseminated following the CO-Synch protocol (d0). On d16 after insemination, reproductive tracts of heifers were collected …

Proteomic Analyses Identify Differences Between Bovine Epididymal And Ejaculated Spermatozoa That Contribute To Longevity, Saulo Menegatti Zoca, Emmalee J. Northrop-Albrecht, Julie A. Walker, Robert A. Cushman, George A. Perry

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Sperm are stored for extended periods of time in the epididymis, but upon ejaculation motility is increased and lifespan is decreased. The objective of this study was to identify differences in proteins between epididymis and ejaculated samples that are associated with longevity. Ejaculated semen was collected from mature Angus bulls (n = 9); bulls were slaughtered and epididymal semen was collected. Epididymal and ejaculated semen were centrifuged to separate sperm and fluid. Fluids were removed and sperm pellets were resuspended in a high ionic solution and vortexed to remove loosely attached proteins. Sperm samples were centrifuged, and the supernatant was …

Effects Of Increasing Dietary Zinc Sulfate Fed To Gestating Ewes: Ii. Milk Somatic Cell Count, Microbial Populations, And Fatty Acid Composition, C. M. Page, R. M. Knuth, T. W. Murphy, D. C. Rule, B. Bisha, J. B. Taylor, W. C. Stewart

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Objective: The objective of the research was to evaluate the effects of increasing dietary Zn sulfate concentration for primiparous gestating ewes on subsequent milk SCC, intramammary microbial identifications, and fatty acid composition.

Materials and Methods: Commercial white-face (WF; n = 27) and black-face (BF; n = 24) ewes (age ≈18 mo; BW = 87.48 ± 8.37 kg) were sorted into breed-type groups and within groups ranked by BW, and then, they were randomly divided into 3 dietary supplement treatment groups: CON (n = 13; 40 mg/kg Zn; ≈1 × NASEM recommendations), Zn500 (n = 21; 500 mg/kg Zn; …

Effects Of Harvest Season On Carcass Characteristics Of Lambs In The Intermountain West, J. R. Whaley, T. W. Murphy, C. L. Gifford, W. J. Means, J. P. Ritten, H. N. Mckibben, C. M. Page, W. C. Stewart

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Objective: The objectives of this study were to survey characteristics including hot carcass weight (HCW), 12th rib fat thickness (RFT), body-wall thickness (BWT), longissimus muscle area (LMA), USDA yield grade (USDA YG), percentage closely trimmed retail cuts (RC), and calculated yield grade (Calc YG) of lamb carcasses in the Intermountain West to determine the effects of season of slaughter and interrelationships among carcass characteristics.

Materials and Methods: Lamb carcass characteristics were evaluated in 2 commercial Intermountain West processing plants over one year (n = 10,027). Carcasses were evaluated by season: spring (December–April, n = 2,322) and summer (May–August, n …