Meat Science Commons^™

Factors Affecting Trailer Thermal Environment Experienced By Market Pigs Transported In The Us, Y Xiong, Richard S. Gates, Angela R. Green-Miller

Department of Animal Science: Faculty Publications

Extreme weather conditions challenge pig thermoregulation during transport and are addressed by the National Pork Board (NPB) Transport Quality Assurance® (TQA) program that provides guidelines for trailer boarding, bedding, and misting. These guidelines are widely applied, yet very little is known about the microenvironment within the trailer. In this study, TQA guidelines (V4) were evaluated via extensive thermal environment measurements during transport in order to evaluate spatial variability and implications on ventilation pattern. Effects of trailer management strategies including bedding, boarding, and misting were examined and the trailer was monitored for interior temperature rise and THI responses within six separate …

The Impact Of Selective Genotyping On The Response To Selection Using Single-Step Genomic Best Linear Unbiased Prediction, Jeremy T. Howard, Thomas A. Rathje, Caitlyn E. Bruns, Danielle F. Wilson-Wells, Stephen D. Kachman, Matthew L. Spangler

Department of Animal Science: Faculty Publications

Across the majority livestock species, routinely collected genomic and pedigree information has been incorporated into evaluations using single-step methods. As a result, strategies that reduce genotyping costs without reducing the response to selection are important as they could have substantial economic impacts on breeding programs. Therefore, the objective of the current study was to investigate the impact of selectively genotyping selection candidates on the selection response using simulation. Populations were simulated to mimic the genome and population structure of a swine and cattle population undergoing selection on an index comprised of the estimated breeding values (EBV) for 2 genetically correlated …

Acute Exposure Of Primary Rat Soleus Muscle To Zilpaterol Hcl (Β2 Adrenergic Agonist), Tnfα, Or Il-6 In Culture Increases Glucose Oxidation Rates Independent Of The Impact On Insulin Signaling Or Glucose Uptake, Caitlin N. Cadaret, Kristin A. Beede, Hannah E. Riley, Dustin T. Yates

Department of Animal Science: Faculty Publications

Recent studies show that adrenergic agonists and inflammatory cytokines can stimulate skeletal muscle glucose uptake, but it is unclear if glucose oxidation is similarly increased. Thus, the objective of this study was to determine the effects of ractopamine HCl (β1 agonist), zilpaterol HCl (β2 agonist), TNFα, and IL-6 on glucose uptake and oxidation rates in unstimulated and insulin-stimulated soleus muscle strips from adult Sprague-Dawley rats. Effects on phosphorylation of Akt (phospho-Akt), p38 MAPK (phospho-p38), and p44/42 MAPK (phospho-p44/42) was also determined. Incubation with insulin increased (P < 0.05) glucose uptake by ~47%, glucose oxidation by ~32%, and phospho-Akt by ~238%. Insulin also increased (P < 0.05) phospho-p38, but only after 2 hours in incubation. Muscle incubated with β2 agonist alone exhibited ~20% less (P < 0.05) glucose uptake but ~32% greater (P < 0.05) glucose oxidation than unstimulated muscle. Moreover, co-incubation with insulin + β2 agonist increased (P < 0.05) glucose oxidation and phospho-Akt compared to insulin alone. Conversely, β1 agonist did not appear to affect basal or insulin-stimulated glucose metabolism, and neither β agonist affected phospho-p44/42. TNFα and IL-6 increased (P < 0.05) glucose oxidation by ~23% and ~33%, respectively, in the absence of insulin. This coincided with increased (P < 0.05) phospho-p38 and phospho-p44/42 but not phospho-Akt. Furthermore, co-incubation of muscle with insulin + either cytokine yielded glucose oxidation rates that were similar to insulin alone, despite lower (P < 0.05) phospho-Akt. Importantly, cytokine-mediated increases in glucose oxidation rates were not concomitant with greater glucose uptake. These results show that acute β2 adrenergic stimulation, but not β1 stimulation, directly increases fractional glucose oxidation in the absence of insulin and synergistically increases glucose oxidation when combined with insulin. The cytokines, TNFα and IL-6, likewise directly increased glucose oxidation in the absence of insulin, but were not additive in combination with insulin and in fact appeared to disrupt Akt-mediated insulin signaling. Rather, cytokines appear to be acting through MAPKs to elicit effects on glucose oxidation. Regardless, stimulation of glucose oxidation by these key stress factors did not rely upon greater glucose uptake, which may promote metabolic efficiency during acute stress by increasing fractional glucose oxidation without increasing total glucose consumption by muscle.

Asas-Ssr Triennnial Reproduction Symposium: Looking Back And Moving Forward—How Reproductive Physiology Has Evolved: Fetal Origins Of Impaired Muscle Growth And Metabolic Dysfunction: Lessons From The Heat-Stressed Pregnant Ewe, Dustin T. Yates, Jessica Lynn Petersen, Ty B. Schmidt, Caitlin N. Cadaret, Taylor L. Barnes, Robert J. Posont, Kristin A. Beede

Department of Animal Science: Faculty Publications

Intrauterine growth restriction (IUGR) is the second leading cause of perinatal mortality and predisposes offspring to metabolic disorders at all stages of life. Muscle-centric fetal adaptations reduce growth and yield metabolic parsimony, beneficial for IUGR fetal survival but detrimental to metabolic health after birth. Epidemiological studies have reported that IUGRborn children experience greater prevalence of insulin resistance and obesity, which progresses to diabetes, hypertension, and other metabolic disorders in adulthood that reduce quality of life. Similar adaptive programming in livestock results in decreased birth weights, reduced and inefficient growth, decreased carcass merit, and substantially greater mortality rates prior to maturation. …

Changes In Myoblast Responsiveness To Tnfα And Il-6 Contribute To Decreased Skeletal Muscle Mass In Intrauterine Growth Restricted Fetal Sheep, Robert J. Posont, Kristin A. Beede, Sean W. Limesand, Dustin T. Yates

Department of Animal Science: Faculty Publications

Intrauterine growth restriction (IUGR) is a leading cause of perinatal morbidity and mortality (Alisi et al., 2011). Skeletal muscle growth is disproportionately reduced in IUGR fetuses and offspring (Padoan et al. 2004; Yates et al. 2014). These individuals present with reduced muscle mass and increased risk for metabolic disorders at all stages of life (Godfrey and Barker, 2000; Yates et al. 2016.). Muscle growth requires proliferation, differentiation, and fusion of myoblasts (muscle stem cells) to form muscle fibers early in gestation and to increase myonuclear content of existing fibers during late gestation and after birth (Yates et al., 2014). These …

Impaired Muscle Stem Cell Function In Cows With High Concentrations Of Androstenedione In Their Follicular Fluid, Taylor L. Barnes, Kiristen A. Beede, Elena M. Merrick, Caitlin N. Cadaret, Andrea S. Cupp, Dustin T. Yates

Department of Animal Science: Faculty Publications

It is unclear whether androstenedione (A4) increases muscle mass and strength similar to testosterone or whether it produces primarily catabolic effects on muscle-like estrogen (Rasmussen et al., 2000). Summers et al. (2014) observed two populations of cows that exhibit either high (>40 ng/mL; High A4) or low (<20 ng/mL; Low A4) concentrations of A4 within the fluid of the dominant follicle just prior to ovulation. High A4 cows had decreased reproductive rates and shorter times before falling out of the herd, but those that did produce calves weaned them ~10-kg heavier than their low A4 counterparts (Summers et al., 2014). It appears that the difference in weights is due to faster growing and more efficient skeletal muscle. High A4 cows share many characteristics with women suffering from polycystic ovary syndrome (PCOS), whose high levels of circulating androgens are associated with changes in body composition (Kirchengast and Huber, 2001).

Performance And Carcass Characteristics Of Steers Fed With Two Levels Of Metabolizable Energy Intake During Summer And Winter Season, R A. Arias, J P. Keim, M Gandarillas, A Velasquez, C Alvarado-Gilis, T L. Mader

Department of Animal Science: Faculty Publications

Climate change is producing an increase on extreme weather events around the world such as flooding, drought and extreme ambient temperatures impacting animal production and animal welfare. At present, there is a lack of studies addressing the effects of climatic conditions associated with energy intake in finishing cattle in South American feed yards. Therefore, two experiments were conducted to assess the effects of environmental variables and level of metabolizable energy intake above maintenance requirements (MEI) on performance and carcass quality of steers. In each experiment (winter and summer), steers were fed with 1.85 or 2.72 times of their requirements of …

Sustained Maternal Inflammation During The Early Third Trimester Yields Fetal Adaptations That Impair Subsequent Skeletal Muscle Growth And Glucose Metabolism In Sheep, Cailtin N. Cadaret, Elena M. Merrick, Taylor L. Barnes, Kristin A. Beede, Robert J. Posont, Jessica Lynn Petersen, Dustin T. Yates

Department of Animal Science: Faculty Publications

Intrauterine growth restriction (IUGR) is linked to metabolic dysfunction in offspring, but the mediating mechanisms are still under investigation (Barker et al., 1993). IUGR fetuses adapt to their poor intrauterine environment by repartitioning nutrients to organs critical for survival (i.e., brain, heart) at the expense of tissues such as muscle (Yates et al., 2012c). These developmental adaptations help the fetus to survive in utero but have lifelong consequences in offspring; persistent reduction of highly metabolic muscle mass is detrimental to glucose homeostasis (DeFronzo et al., 1981). Glucose metabolism is regulated primarily by insulin, and nutrient depravation is associated with impaired …

Chronic Maternal Inflammation During Late Gestation Impairs Subsequent Β-Cell Function But Not Islet Growth In Fetal Sheep, M.D. Abebe, C.N. Cadaret, T.B. Barnes, K.A. Beede, D. T. Yates

Department of Animal Science: Faculty Publications

Intrauterine growth restriction (IUGR) greatly increases perinatal mortality and morbidity rates, and leads to much greater risk for metabolic complications later in life. One such complication is the development of glucose intolerance or diabetes, which typically develops concurrently with abhorrent patterns of insulin secretions due to diminished β-cell mass and impaired function as well as an overall reduction in pancreatic endocrine tissue. The mechanisms by which IUGR causes problems with health and function of the pancreatic islets are not well understood. Therefore, our goal for this study was to determine how materno-fetal inflammation (MI) affects β-cell growth and function. To …

Investigation Of The Skeletal Muscle Transcriptome In Lambs Fed Β Adrenergic Agonists And Subjected To Heat Stress For 21 D, Rachel Kubik, Shauna M. Tietze, Ty B. Schmidt, Dustin Tyler Yates, Jessica Lynn Petersen

Department of Animal Science: Faculty Publications

Dietary β-adrenergic agonists (β-AA) are used in livestock to increase muscle protein accretion and decrease adipose deposition during the last 20 to 40 d of the finishing period (Johnson et al., 2014). These β-AA act through specific seven transmembrane receptors and are classified by the receptor isoform to which they primarily bind (Mersmann, 1998). Two β-AA are approved for use in beef cattle in the United States: ractopamine HCl (RAC, β1 agonist) and zilpaterol HCl (ZH, β2 agonist) (Johnson et al., 2014). Supplementation of β-AA increases efficiency of the animal and results in a leaner carcass (Elam et al., 2009). …

Shinyaim: Shiny‐Based Application Of Interactive Manhattan Plots For Longitudinal Genome‐Wide Association Studies, Waseem Hussain, Malachy T. Campbell, Harkamal Walia, Gota Morota

Department of Animal Science: Faculty Publications

Owning to advancements in sensor‐based, non‐destructive phenotyping platforms, researchers are increasingly collecting data with higher temporal resolution. These phenotypes collected over several time points are cataloged as longitudinal traits and used for genome‐wide association studies (GWAS). Longitudinal GWAS typically yield a large number of output files, posing a significant challenge to data interpretation and visualization. Efficient, dynamic, and integrative data visualization tools are essential for the interpretation of longitudinal GWAS results for biologists; however, these tools are not widely available to the community. We have developed a flexible and user‐friendly Shiny‐based online application, ShinyAIM, to dynamically view and interpret temporal …

National Beef Quality Audit–2016: Assessment Of Cattle Hide Characteristics, Offal Condemnations, And Carcass Traits To Determine The Quality Status Of The Market Cow And Bull Beef Industry, Mckensie K. Harris, L. Clay Eastwood, Courtney A. Boykin, Ashley N. Arnold, Kerri B. Gehring, Daniel S. Hale, Christopher R. Kerth, Davey B. Griffin, J.W. Savell, Keith E. Belk, Dale R. Woerner, Josh D. Hasty, Jennifer N. Martin, Ty E. Lawrence, Trenton J. Mcevers, Deborah L. Vanoverbeke, Gretchen G. Mafi, Morgan M. Pfeiffer, Ty B. Schmidt, Robert J. Maddock, D. Dwain Johnson, Chad C. Carr, Jason M. Scheffler, T. Dean Pringle, Alexander M. Stelzleni, Robert J. Delmore Jr.

Department of Animal Science: Faculty Publications

To continue the series that began in 1994, the National Beef Quality Audit (NBQA) – 2016 was conducted to quantify the quality status of the market cow and bull beef sector, as well as determine improvements made in the beef and dairy industry since 2007. The NBQA-2016 was conducted from March through December of 2016, and assessed hide-on carcasses (n = 5,278), chilled carcasses (n = 4,285), heads (n = 5,720), and offal items (n = 4,800) in 18 commercial processing facilities throughout the United States. Beef cattle were predominantly black-hided; 68.0% of beef cows and 67.2% of beef bulls …

Research Note Prediction Model For Manure Zinc Excretion In Laying Hens, Kelli M. Martin, N. Vargas-Jurado, S. E. Purdum

Department of Animal Science: Faculty Publications

The objective of this research trial was to compare 2 sources of zinc and different levels of supplementation on manure zinc excretion in laying hens. Bovan White Leghorn hens were used in this study and fed one of 6 dietary treatments. Treatments were in a 2 × 3 factorial arrangement with 2 sources of zinc (zinc sulfate or Availa R < Zn) and 3 levels (40, 80, or 120 ppm) and were randomly assigned to 48 cages with 5 hens/cage and 8 replicates/treatment. Hens were housed in a tiered manure-belt housing system providing 627.1 cm2/hen and were given access to 110 g/hen/d of feed. Manure samples were collected, and manure zinc content was calculated at 10- week intervals. Data were analyzed using the Glimmix procedure in SAS. There was a significant overall effect of source (P < 0.0001) for zinc content, such that hens fed zinc sulfate had lower amounts of zinc excretion. There was also a significant level effect (P < 0.0001) in which hens fed 120 ppm zinc excreted the greatest amount of zinc. A significant source by level interaction was observed (P < 0.0001) for both the overall and individual analyses, such that 120 ppm Availa R < Zn showed the highest zinc excretion, and both 40 ppm zinc sulfate and Availa R < Zn showed the lowest zinc excretion. Based on these results, a prediction equation was written for an estimated amount of zinc excretion based on the amount of zinc provided in the diet.

Including Phenotypic Causal Networks In Genome-Wide Association Studies Using Mixed Effects Structural Equation Models, Mehdi Momen, Ahmad Ayatollahi Mehrgardi, Mahmoud Amiri Roudbar, Andreas Kranis, Renan Mercuri Pinto, Bruno D. Valente, Gota Morota, Guilherme J.M. Rosa, Daniel Gianola

Department of Animal Science: Faculty Publications

Background: Phenotypic networks describing putative causal relationship among multiple phenotypes can be used to infer single-nucleotide polymorphism (SNP) effects in genome-wide association studies (GWAS). In GWAS with multiple phenotypes, reconstructing underlying causal structures among traits and SNPs using a single statistical framework is essential for understanding the entirety of genotype-phenotype maps. A structural equation model (SEM) can be used for such purpose.

Methods: We applied SEM to GWAS (SEM-GWAS) in chickens, taking into account putative causal relationships among body weight (BW), breast meat (BW), hen-house production (HHP), and SNPs. We assessed the performance of SEM-GWAS by comparing the model results …

Big Data Analytics And Precision Animal Agriculture Symposium: Machine Learning And Data Mining Advance Predictive Big Data Analysis In Precision Animal Agriculture, Gota Morota, Ricardo V. Ventura, Fabyano F. Silva, Masanori Koyama, Samodha C. Fernando

Department of Animal Science: Faculty Publications

Precision animal agriculture is poised to rise to prominence in the livestock enterprise in the domains of management, production, welfare, sustainability, health surveillance, and environmental footprint. Considerable progress has been made in the use of tools to routinely monitor and collect information from animals and farms in a less laborious manner than before. These efforts have enabled the animal sciences to embark on information technology-driven discoveries to improve animal agriculture. However, the growing amount and complexity of data generated by fully automated, high-throughput data recording or phenotyping platforms, including digital images, sensor and sound data, unmanned systems, and information obtained …

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 …

Using Single Molecule Mrna Fluorescent In Situ Hybridization (Rna-Fish) To Quantify Mrnas In Individual Murine Oocytes And Embryos, Fang Xie, Kelsey A. Timme, Jennifer R. Wood

Department of Animal Science: Faculty Publications

Changes in abundance of mRNAs during oocyte growth and maturation and during pre-implantation embryo development have been documented using quantitative real-time RT-PCR (qPCR), microarray analyses, and whole genome sequencing. However, these techniques require amplification of mRNAs, normalization using housekeeping genes, can be biased for abundant transcripts, and/or require large numbers of oocytes and embryos which can be difficult to acquire from mammalian species. We optimized a single molecule RNA fluorescence in situ hybridization (RNA-FISH) protocol, which amplifies fluorescence signal to detect candidate transcripts, for use with individual oocytes and embryos. Quantification using the software Localize showed patterns of Gdf9 and …

The Influence Of Fat And Hemicellulose On Methane Production And Energy Utilization In Lactating Jersey Cattle, O. R. Drehmel, T. M. Brown-Brandl, J. V. Judy, S. C. Fernando, P. S. Miller, K. E. Hales, Paul J. Kononoff

Department of Animal Science: Faculty Publications

Feeding fat to lactating dairy cows may reduce methane production. Relative to cellulose, fermentation of hemicellulose is believed to result in less methane; however, these factors have not been studied simultaneously. Eight multiparous, lactating Jersey cows averaging (±SD) 98 ± 30.8 d in milk and body weight of 439.3 ± 56.7 kg were used in a twice-replicated 4 × 4 Latin square to determine the effects of fat and hemicellulose on energy utilization and methane production using a headbox-type indirect calorimetry method. To manipulate the concentration of fat, porcine tallow was included at either 0 or 2% of the diet …

Synaptogyrin-2 Influences Replication Of Porcine Circovirus 2, Lianna R. Walker, Taylor B. Engle, Hiep Vu, Emily R. Tosky, Dan J. Nonneman, Timothy P. L. Smith, Tudor Borza, Thomas E. Burkey, Graham S. Plastow, Stephen D. Kachman, Daniel C. Ciobanu

Department of Animal Science: Faculty Publications

Porcine circovirus 2 (PCV2) is a circular single-stranded DNA virus responsible for a group of diseases collectively known as PCV2 Associated Diseases (PCVAD). Variation in the incidence and severity of PCVAD exists between pigs suggesting a host genetic component involved in pathogenesis. A large-scale genome-wide association study of experimentally infected pigs (n = 974), provided evidence of a host genetic role in PCV2 viremia, immune response and growth during challenge. Host genotype explained 64% of the phenotypic variation for overall viral load, with two major Quantitative Trait Loci (QTL) identified on chromosome 7 (SSC7) near the swine leukocyte antigen complex …

The Impact Of Truncating Data On The Predictive Ability For Single-Step Genomic Best Linear Unbiased Prediction, Jeremy T. Howard, Thomas A. Rathje, Caitlyn E. Bruns, Danielle F. Wilson-Wells, Stephen D. Kachman, Matthew L. Spangler

Department of Animal Science: Faculty Publications

Simulated and swine industry data sets were utilized to assess the impact of removing older data on the predictive ability of selection candidate estimated breeding values (EBV) when using single-step genomic best linear unbiased prediction (ssGBLUP). Simulated data included thirty replicates designed to mimic the structure of swine data sets. For the simulated data, varying amounts of data were truncated based on the number of ancestral generations back from the selection candidates. The swine data sets consisted of phenotypic and genotypic records for three traits across two breeds on animals born from 2003 to 2017. Phenotypes and genotypes were iteratively …

Effect Of Differing Ingredients And Packaging Technologies On The Color Of High-Pressure Processed Ground Beef, Jhinuk Gupta, Chad G. Bower, Gary Sullivan, George A. Cavender

Department of Animal Science: Faculty Publications

High-pressure processing (HPP) is a nonthermal pasteurization technique to control pathogens, like Escherichia coli. However, color changes in raw beef induced by HPP restrict its use within the beef industry. ­e objectives of this study were to investigate the effects of adding curing agents (nitrite) and packaging with or without reducing compounds (ascorbic acid/erythorbate) on color retention in high-pressure processed ground beef. Color was measured (CIE L*a*b*) before HPP and on days 3, 7, 12, 14, 19, and 21 after HPP. Statistical analysis (SAS GLIMMIX) was run to identify the main effects of adding curing agents, packaging, and …

Fecal Microbiota Transplantation Is Associated With Reduced Morbidity And Mortality In Porcine Circovirus Associated Disease, Megan C. Niederwerder, Laura A. Constance, Raymond R. R. Rowland, Waseem Abbas, Samodha C. Fernando, Megan L. Potter, Maureen A. Sheahan, Thomas E. Burkey, Richard A. Hesse, Ada G. Cino-Ozuna

Department of Animal Science: Faculty Publications

Porcine circovirus associated disease (PCVAD) is a term used to describe the multifactorial disease syndromes caused by porcine circovirus type 2 (PCV-2), which can be reproduced in an experimental setting through the co-infection of pigs with PCV-2 and porcine reproductive and respiratory syndrome virus (PRRSV). The resulting PCVAD-affected pigs represent a subpopulation within the co-infected group. In co-infection studies, the presence of increased microbiome diversity is linked to a reduction in clinical signs. In this study, fecal microbiota transplantation (FMT) was investigated as a means to prevent PCVAD in pigs co-infected with PRRSV and PCV-2d. The sources of the FMT …

Genome-Wide Association Study Of Stayability And Heifer Pregnancy In Red Angus Cattle, S. E. Speidel, B. A. Buckley, R. J. Boldt, R. M. Enns, J. Lee, Matthew L. Spangler, M. G. Thomas

Department of Animal Science: Faculty Publications

Reproductive performance is the most important component of cattle production from the standpoint of economic sustainability of commercial beef enterprises. Heifer Pregnancy (HPG) and Stayability (STAY) genetic predictions are 2 selection tools published by the Red Angus Association of America (RAAA) to assist with improvements in reproductive performance. Given the importance of HPG and STAY to the profitability of commercial beef enterprises, the objective of this study was to identify QTL associated with both HPG and STAY in Red Angus cattle. A genome-wide association study (GWAS) was performed using deregressed HPG and …

Do Stronger Measures Of Genomic Connectedness Enhance Prediction Accuracies Across Management Units?, Haipeng Yu, Matthew L. Spangler, Ronald M. Lewis, Gota Morota

Department of Animal Science: Faculty Publications

Genetic connectedness assesses the extent to which estimated breeding values can be fairly compared across management units. Ranking of individuals across units based on best linear unbiased prediction (BLUP) is reliable when there is a sufficient level of connectedness due to a better disentangling of genetic signal from noise. Connectedness arises from genetic relationships among individuals. Although a recent study showed that genomic relatedness strengthens the estimates of connectedness across management units compared with that of pedigree, the relationship between connectedness measures and prediction accuracies only has been explored to a limited extent. In this study, we examined whether increased …

Genome-Wide Association Study For Feed Efficiency Traits Using Snp And Haplotype Models, Kashly Rene Schweer, Stephen D. Kachman, Larry A. Kuehn, Harvey Freetly, John E. Pollak, Matthew L. Spangler

Department of Animal Science: Faculty Publications

Feed costs comprise the majority of variable expenses in beef cattle systems making feed efficiency an important economic consideration within the beef industry. Due to the expense of recording individual feed-intake phenotypes, a genomic-enabled approach could be advantageous toward improving this economically relevant trait complex. A genome-wide association study (GWAS) was performed using 748 crossbred steers and heifers representing seven sire breeds with phenotypes for ADG and ADFI. Animals were genotyped with the BovineSNP50v2 BeadChip containing approximately 54,000 SNP. Both traits were analyzed using univariate SNPbased (BayesC) and haplotype-based (BayesIM) models and jointly using BayesIM to perform a bivariate GWAS. …

Risks Associated To Different Methods Of Increasing Pregnancy Rate Of Cows In Cow-Calf Systems, Tamara Esteves De Oliveira, Julio Otavio Jardim Barcellos, Jack Whittier, Odilene De Souza Teixeira, David Santos De Freitas, Ricardo Pedroso Oaigen, Matheus Dhein Dill, Concepta Mcmanus

Department of Animal Science: Faculty Publications

This study assessed the risks of different management practices to increase pregnancy rate in beef cow-calf systems, aiming at assisting decision-making. The perception of 18 experts on animal sciences regarding the risks of 32 nutritional, breeding, and general management practices applied to increase pregnancy rate were evaluated through questionnaires. The experts were selected by a non-probability sampling of researchers on veterinary and animal sciences. In addition, five farmers and eight technical consultants were also selected. The questionnaire was applied during a face-to-face meeting. The risk of each practice was assessed according to four factors, namely, cost, technical knowledge, operational complexity, …

Energy Balance And Diurnal Variation In Methane Production As Affected By Feeding Frequency In Jersey Cows In Late Lactation, J. V. Judy, G. C. Bachman, T. M. Brown-Brandl, S. C. Fernando, K. E. Hales, P. S. Miller, R. R. Stowell, P. J. Kononoff

Department of Animal Science: Faculty Publications

Methane (CH₄) production of ruminants typically increases with increased dry matter intake (DMI). However, few studies have observed the effects of feeding multiple times a day and its effects on diurnal variation in CH₄ production and energy balance in late-lactation dairy cattle. A study using headbox-style indirect calorimetry and 12 multiparous (225 ± 16.2 d in milk; mean ± SD) lactating Jersey cows was conducted to determine the effects of feeding twice daily on diurnal variation in CH₄ production and total energy balance. A crossover design with 14-d periods (10 d of adaption and 4 d …

Rumen Bacterial Composition In Lambs Is Affected By Β-Adrenergic Agonist Supplementation And Heat Stress At The Phylum Level, Erin M. Duffy, Shauna M. Tietze, Allison L. Knoell, Nirosh D. Aluthge, Samodha C. Fernando, Ty B. Schmidt, Dustin T. Yates, Jessica L. Petersen

Department of Animal Science: Faculty Publications

The rumen has several important physiological functions, including absorption, transport, metabolic activity, and host protection (Roh et al., 2007). The rumen is extensively researched due to the importance of ruminants in agriculture and the major role played by rumen microbes in nutrient utilization and health of the ruminant animal. The microbial community of the rumen is altered by diet (McCann et al., 2014), age (Jami et al., 2013), and environment.

Triennial Reproduction Symposium: Looking Back And Moving Forward—How Reproductive Physiology Has Evolved, Deb L. Hamernik, Andrea S. Cupp, John S. Davis

Department of Animal Science: Faculty Publications

In honor of the 50th anniversary of the Society for the Study of Reproduction (SSR), a Triennial Reproduction Symposium was cosponsored by SSR and the American Society of Animal Science (ASAS). The Society for the Study of Reproduction was formed in 1967 when a group of reproductive biologists that were members of ASAS met with physician scientists and decided to organize a new scientific society. The goal of SSR was to promote the study of reproduction by fostering interdisciplinary communication among scientists, holding conferences, and publishing meritorious studies. Today after its 50th anniversary, the mission for SSR is to harness …

Function And Dysfunction Of Fatty Acid Mobilization: A Review, Joslyn K. Beard, Travis Mulliniks, Dustin T. Yates

Department of Animal Science: Faculty Publications

Western populations have a growing obesity epidemic due in part to excessive nutrient intake from high-fat diets, which are increasingly common. Overindulgence of nutrients is associated with a greater incidence of metabolic dysfunction and a greater risk for obesity, diabetes, hypertension, and other metabolic disorders that lower quality of life. Research in humans and animal models has improved our understanding of how excess circulating free fatty acids negatively impact the ability of muscle and other tissues to regulate nutrient uptake and utilization. It is generally accepted by the scientific community that excess circulating fatty acids lead to insulin resistance, but …