Genetics and Genomics Commons^™

Development Of A Row-Crop Tractor Data Acquisition System, James Roeber, Santosh Pitla, Roger M. Hoy, Joe D. Luck

Department of Animal Science: Faculty Publications

Numerous advancements in machinery performance on row-crop agricultural tractors have been made in recent years. Currently, the Organisation for Economic Co-operation and Development (OECD) only tests predetermined points (E.g., max. power, max. torque) for drawbar and hydraulic power. This method of testing has been used for many years with the tractor at a steady state which is usually not typical of row-crop operations. A data acquisition system (DAQ) was designed that records implement energy consumption (E.g., drawbar loading, PTO power, and hydraulic power). The system used a LabVIEW program and a compact data acquisition system (cDAQ) to record data from …

An Application Of Mesh Enrichment Analysis In Livestock, Gota Morota, F. Moreno, James L. Petersen, Daniel C. Ciobanu, K. Tsuyuzaki, I. Nikaido

Department of Animal Science: Faculty Publications

An integral part of functional genomics studies is to assess the enrichment of specific biological terms in lists of genes found to be playing an important role in biological phenomena. Contrasting the observed frequency of annotated terms with those of the background is at the core of overrepresentation analysis (ORA). Gene Ontology (GO) is a means to consistently classify and annotate gene products and has become a mainstay in ORA. Alternatively, Medical Subject Headings (MeSH) offers a comprehensive life science vocabulary including additional categories that are not covered by GO. Although MeSH is applied predominantly in human and model organism …

Optimizing The Use Of Fibrous Residues In Beef And Dairy Diets, James C. Macdonald, G. E. Erickson, P. J. Kononoff, T. J. Klopfenstein

Department of Animal Science: Faculty Publications

Increased corn prices over the past decade have altered land use away from traditional forage in favor of corn. Accordingly, beef and dairy producers have had to adopt non-traditional forage resources into their production systems, many of which have become available as a result of increased corn production. Byproducts of the wet and dry milling industries have been used to replace both corn and forage in beef and dairy diets. Byproducts containing corn bran have large amounts of readily digestible hemicellulose. The use of byproducts may increase milk production, ADG, and G:F in dairy, beef growing, and beef finishing diets, …

Microbial Diversity And Activity In The Nematostella Vectensis Holobiont: Insights From 16s Rrna Gene Sequencing, Isolate Genomes, And A Pilot-Scale Survey Of Gene Expression, Jia Y. Har, Tim Helbig, Ju H. Lim, Samodha C. Fernando, Adam M. Reitzel, Kevin Penn, Janelle R. Thompson

Department of Animal Science: Faculty Publications

We have characterized the molecular and genomic diversity of the microbiota of the starlet sea anemone Nematostella vectensis, a cnidarian model for comparative developmental and functional biology and a year-round inhabitant of temperate salt marshes. Molecular phylogenetic analysis of 16S rRNA gene clone libraries revealed four ribotypes associated with N. vectensis at multiple locations and times. These associates include two novel ribotypes within the ε-Proteobacterial order Campylobacterales and the Spirochetes, respectively, each sharing 99% 16S rRNA identity with Endozoicomonas elysicola and Pseudomonas oleovorans, respectively. Species-specific PCR revealed that these populations persisted in N. vectensis asecually propagated under laboratory …

Exogenous Administration Of Lipids To Steers Alters Aspects Of The Innate Immune Response To Endotoxin Challenge, Nicole C. Burdick Sanchez, Jeffery A. Carroll, Janet R. Donaldson, Joe O. Buntyn, Ty B. Schmidt

Department of Animal Science: Faculty Publications

This study examined the effects of increasing energy availability from both dextrose and lipid treatments on the proinflammatory response to LPS in Holstein steers. Steers were randomly assigned to one of three groups: saline at 0.5 ml/ kg body weight (Control) or 50% dextrose [0.5 ml/kg body weight (Dextrose) to mimic calm cattle’s response to LPS] administered immediately prior to LPS (0.5 mg/kg body weight at 0 h) or continuous lipid emulsion infusion from –1 to 6 h [Intralipid 20% (Baxter, Deerfield, IL USA); 0.5 ml/kg/hr (Lipid) to mimic temperamental cattle]. Concentrations of non-esterified fatty acids (NEFA) were greater in …

Mesh Ora Framework: R/Bioconductor Packages To Support Mesh Over-Representation Analysis, Koki Tsuyuzaki, Gota Morota, Manabu Ishii, Takeru Nakazato, Satoru Miyazaki, Itoshi Nikaido

Department of Animal Science: Faculty Publications

Background: In genome-wide studies, over-representation analysis (ORA) against a set of genes is an essential step for biological interpretation. Many gene annotation resources and software platforms for ORA have been proposed. Recently, Medical Subject Headings (MeSH) terms, which are annotations of PubMed documents, have been used for ORA. MeSH enables the extraction of broader meaning from the gene lists and is expected to become an exhaustive annotation resource for ORA. However, the existing MeSH ORA software platforms are still not sufficient for several reasons.

Results: In this work, we developed an original MeSH ORA framework composed of six types of …

A Cooperative Study On The Standardized Total-Tract Digestible Phosphorus Requirement Of Twenty-Kilogram Pigs, O. Adeola, M. J. Azain, S. D. Carter, T. D. Crenshaw, M. J. Estienne, B. J. Kerr, M. D. Lindemann, C. V. Maxwell, P. S. Miller, M. C. Shannon, E. Van Heugten

Department of Animal Science: Faculty Publications

A cooperative study comprising growth performance, bone mineralization, and nutrient balance experiments was conducted at 11 stations to determine the standardized total-tract digestible (STTD) P requirement of 20-kg pigs using broken-line regression analysis. Monocalcium phosphate and limestone were added to a corn–soybean meal–based diet at the expense of cornstarch to establish 6 concentrations of STTD P from 1.54 to 5.15 g/kg in increments of 0.62 g/kg at a constant Ca:total P of 1.52:1.0. Diets were fed to 936 pigs (average initial BW of 19 kg) in 240 pens for 20 replicate pens of barrows and 20 replicate pens of gilts …

Yield And Forage Value Of A Dual-Purpose Bmr-12 Sorghum Hybrid, Melinda K. Yerka, Andrea K. Pederson, J. J. Toy, Galen E. Erickson, Jeffrey F. Pedersen, Rob B. Mitchell

Department of Animal Science: Faculty Publications

Grain sorghum [Sorghum bicolor (L.) Moench] is an important crop for rainfed production systems with 2.7 million ha grown in the United States in 2013. The brown-midrib (bmr) mutations, especially bmr-12, have resulted in low stover lignin and high fiber digestibility without reducing grain yield in some sorghum lines. However, the effect of the bmr trait on beef cattle (Bos taurus) performance when grazing crop residue is unknown. Our objectives were to validate previous small-plot results reporting no grain yield difference between near-isogenic bmr-12 (BMR) and wild-type control (CON) A Wheatland × R

Tx430 …

Cattle With Increased Severity Of Bovine Respiratory Disease Complex Exhibit Decreased Capacity To Protect Against Histone Cytotoxicity, J. A. Matera, B. K. Krehbiel, J. A. Hernandez Gifford, D. L. Step, C. R. Krehbiel, C. A. Gifford

Department of Animal Science: Faculty Publications

Bovine respiratory disease complex (BRDC) is the leading cause of morbidity and mortality in feedlot cattle. Significant inflammation and lesions are often observed in lungs of infected cattle. During acute inflammatory responses, histones contribute to mortality in rodents and humans and serum proteins can protect against histone-induced cytotoxicity. We hypothesized that cattle experiencing chronic or fatal cases of BRDC have reduced ability to protect against cytotoxic effects of histones. Serum samples were collected from 66 bull calves at the time of normal feedlot processing procedures. Animals were retrospectively assigned to groups consisting of calves never treated for BRDC (control [CONT]; …

The Effects Of Technology Use In Feedlot Production Systems On Feedlot Performance And Carcass Characteristics, C. L. Maxwell, B. C. Wilson, C. F. O'Neill, B. K. Wilson, C. G. Hixon, C. L. Haviland, A. N. Grimes, M. S. Calvo-Lorenzo, D. L. Vanoverbeke, G. G. Mafi, C. J. Richards, D. L. Step, B. P. Holland, C. R. Krehbiel

Department of Animal Science: Faculty Publications

The objectives of this study were to examine the effects of feedlot production systems with and without the use of a β-adrenergic agonist compared to an all-natural production program on feedlot performance and carcass characteristics. Crossbred beef steers (n = 336; initial BW = 379 ± 8 kg) were randomized to 1 of 3 treatments in a randomized complete block design (RCBD; 14 steers/pen; 8 pens/treatment). Treatments consisted of an all-natural treatment (NAT), a conventional treatment (CONV), and a conventional treatment with a β-agonist (CONV-Z). All treatments were fed the same basal diet with NAT cattle receiving no growth promoting …

Genetic Parameter Estimates And Breed Effects For Calving Difficulty And Birth Weight In A Multi-Breed Population, Cashley Ahlberg

Department of Animal Science: Dissertations, Theses, and Student Research

There are multiple breeds of beef cattle available to utilize in breeding systems to maximize production and economics. Calving difficulty (dystocia) is a significant cost to beef production and is more prevalent in first-calf heifers. The objectives of this study were to estimate genetic parameters and breed differences for calving difficulty and birth weight as a first step towards the development of across-breed adjustment factors for calving difficulty.

Two models were employed to analyze birth weight (BWT) and calving difficulty (CD) recorded on 4,579 first parity females from the Germplasm Evaluation program at the United States Meat Animal Research Center …

Altered Theca And Cumulus Oocyte Complex Gene Expression, Follicular Arrest And Reduced Fertility In Cows With Dominant Follicle Follicular Fluid Androgen Excess, Adam F. Summers, William E. Pohlmeier, Kevin M. Sargent, Brizett D. Cole, Rebecca J. Vinton, Scott G. Kurz, Renee M. Mcfee, Robert A. Cushman, Andrea S. Cupp, Jennifer R. Wood

Department of Animal Science: Faculty Publications

Aspiration of bovine follicles 12–36 hours after induced corpus luteum lysis serendipitously identified two populations of cows, one with High androstenedione (A4; >40 ng/ml; mean = 102) and another with Low A4 (/ml; mean = 9) in follicular fluid. We hypothesized that the steroid excess in follicular fluid of dominant follicles in High A4 cows would result in reduced fertility through altered follicle development and oocyte maternal RNA abundance. To test this hypothesis, estrous cycles of cows were synchronized and ovariectomy was performed 36 hours later. HPLC MS/MS analysis of follicular fluid showed increased dehydroepiandrosterone (6-fold), A4 (158-fold) and testosterone …

Kernel-Based Whole-Genome Prediction Of Complex Traits: A Review, Gota Morota, Daniel Penagaricano

Department of Animal Science: Faculty Publications

Prediction of genetic values has been a focus of applied quantitative genetics since the beginning of the 20th century, with renewed interest following the advent of the era of whole genome-enabled prediction. Opportunities offered by the emergence of high-dimensional genomic data fueled by post-Sanger sequencing technologies, especially molecular markers, have driven researchers to extend Ronald Fisher and Sewall Wright’s models to confront new challenges. Inparticular, kernel methods are gaining consideration as a regression method of choice for genome-enabled prediction. Complex traits are presumably influenced by many genomic regions working in concert with others (clearly so when considering pathways), thus generating …

Ept7 Influences Estrogen Action In The Pituitary Gland And Body Weight Of Rats, Scott G. Kurz, Kirsten L. Mcfee, Nyssa Becker Samanas, Maureen Peters Hickman, Quincy A. Eckert, Tiffany L. Walker, Andrea S. Cupp, James D. Shull

Department of Animal Science: Faculty Publications

Estrogens control many aspects of pituitary gland biology, including regulation of lactotroph homeostasis and synthesis and secretion of prolactin. In rat models, these actions are strain specific and heritable, and multiple quantitative trait loci (QTL) have been mapped that impact the responsiveness of the lactotroph to estrogens. One such QTL, Ept7, was mapped to RNO7 in female progeny generated in an intercross between BN rats, in which the lactotroph population is insensitive to estrogens, and ACI rats, which develop lactotroph hyperplasia/adenoma and associated hyperprolactinemia in response to estrogen treatment. The primary objective of this study was to confirm the …

Effects Of Il8 And Immune Cells On The Regulation Of Luteal Progesterone Secretion, Heather Talbott, Abigail Delaney, Pan Zhang, Yangsheng Yu, Robert Cushman, Andrea S. Cupp, John S. Davis

Department of Animal Science: Faculty Publications

Recent studies suggest that chemokines may mediate the luteolytic action of PGF2α (PGF). Our objective was to identify chemokines induced by PGF in vivo and to determine the effects of IL8 on specific luteal cell types in vitro. Midcycle cows were injected with saline or PGF, ovaries were removed after 0.5 - 4 h and chemokine expression was analyzed by qPCR. In vitro expression of IL8 was analyzed after PGF administration and with cell signaling inhibitors to determine the mechanism of PGF-induced chemokine expression. Purified neutrophils were analyzed for migration and activation in response to IL8 and PGF. Purified …

Increasing Dietary Neutral Detergent Fiber Concentration Decreases Ruminal Hydrogen Sulfide Concentrations In Steers Fed High-Sulfur Diets Based On Ethanol Coproducts, S. J. Morine, M. E. Drewnoski, S. L. Hansen

Department of Animal Science: Faculty Publications

Cattle feedlot diets commonly contain ethanol coproducts that are high in S. This dietary S is reduced in the rumen by sulfate reducing bacteria, resulting in an accumulation of hydrogen sulfide (H2S), increasing the risk for S toxicity. A negative correlation between H₂S and ruminal pH has been observed previously. The objective of this study was to determine the effect of varying dietary NDF from chopped bromegrass hay (66% NDF) on performance, ruminal pH, and ruminal H2S gas concentration of steers fed a high-S finishing diet. One hundred fifty crossbred steers (359 ± 51 kg BW) were blocked …

High-Sulfur In Beef Cattle Diets: A Review, M. E. Drewnoski, D. J. Pogge, S. L. Hansen

Department of Animal Science: Faculty Publications

While many cattle feeding areas in the United States have long dealt with high sulfate water, increased feeding of ethanol co-products such as distillers grains with solubles to beef cattle has led to a corresponding increase in dietary sulfur. As a result, sulfur metabolism in the ruminant has been the focus of many research studies over the past ten years, and advances in our knowledge have been made. Excessive sulfur in cattle diets may have implications on trace mineral absorption, dry matter intake, and overall cattle growth. This review will focus on what we have learned about the metabolism of …

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 …

Variation In Time And Magnitude Of Immune Response And Viremia In Experimental Challenges With Porcine Circovirus 2b, Taylor B. Engle, Erin E. Jobman, Timonthy W. Moural, Autumn M. Mcknite, Justin W. Bundy, Sarah Y. Barnes, Emily H. Davis, Judith A. Galeota, Thomas E. Burkey, Graham S. Plastow, Stephen D. Kachman, Daniel C. Ciobanu

Department of Animal Science: Faculty Publications

Background: Porcine circovirus 2 is the primary agent responsible for inducing a group of associated diseases known as Porcine Circovirus Associated Diseases (PCVAD), which can have detrimental effects on production efficiency as well as causing significant mortality. The objective of this study was to evaluate variation in viral replication, immune response and growth across pigs (n = 974) from different crossbred lines. The approach used in this study was experimental infection with a PCV2b strain of pigs at an average of 43 days of age.

Results: The sequence of the PCV2b isolate used in the challenge was similar with a …

Quantitative Trait Loci For Energy Balance Traits In An Advanced Intercross Line Derived From Mice Divergently Selected For Heat Loss, Larry J. Leamy, Kari Elo, Merlyn K. Nielsen, Stephanie R. Thorn, William Valdar, Daniel Pomp

Department of Animal Science: Faculty Publications

Obesity in human populations, currently a serious health concern, is considered to be the consequence of an energy imbalance in which more energy in calories is consumed than is expended. We used interval mapping techniques to investigate the genetic basis of a number of energy balance traits in an F₁₁ advanced intercross population of mice created from an original intercross of lines selected for increased and decreased heat loss. We uncovered a total of 137 quantitative trait loci (QTLs) for these traits at 41 unique sites on 18 of the 20 chromosomes in the mouse genome, with X-linked QTLs …

Litter Deposition And Nitrogen Return In Rotationally Stocked Smooth Bromegrass Pastures, John A. Guretzky, Walter H. Schacht, Ana B. Wingeyer, Terry J. Klopfenstein, Andrea K. Watson

Department of Animal Science: Faculty Publications

Understanding how management systems impact nutrient cycling is important to pasture sustainability. From 2010 to 2011, we investigated how supplementation of beef cattle (Bos taurus) with corn (Zea mays L.) dried distillers grains plus solubles (DDGS) on unfertilized, rotationally stocked smooth bromegrass (Bromus inermis Leyss.) pasture (SUPP) affected the litter pool, residual herbage mass, litter deposition, and litter quality relative to unsupplemented beef cattle rotationally stocked on unfertilized control (CONT) and N-fertilized (FERT) smooth bromegrass pastures. As hypothesized based on management for greater herbage mass and animal demand during the grazing season, litter deposition was 48% …

Soil Organic Matter And Root And Rhizome Responses To Management Strategies In Smooth Bromegrass Pastures, John A. Guretzky, Ana B. Nuttelman, Walter H. Schacht, Terry J. Klopfenstein, Andrea K. Watson

Department of Animal Science: Faculty Publications

Soil organic matter (SOM) is a key component of pasture production. This is study investigated how management strategies that varied amount and form of N input in a long-term experiment affected concentrations and stocks of total-soil organic C and N, particulate organic carbon (POC), particulate organic nitrogen (PON), root and rhizome mass, C and N contents in topsoil of smooth bromegrass (Bromus inermis Leyss.) pastures with silty clay loam soils in a wet (2010) and dry (2012) year. Management strategies included: (i) unfertilized pasture grazed with unsupplemented beef cattle (CONT); (ii) unfertilized pasture grazed with dried distillers grains plus …

Analysis Of 28 Generations Of Selection For Reproduction, Growth, And Carcass Traits In Swine, W. L. Hsu, Rodger K. Robinson

Department of Animal Science: Faculty Publications

Selection (28 generations, G) in a Large White–Landrace composite population for traits aimed at increasing live pigs born per litter (BA), with additional selection for increased 180-d weight (WT180) and longissimus muscle area (LMA) and decreased back fat (BF10) in the last 8 generations, was practiced. Objectives herein were to estimate genetic and phenotypic responses and genetic parameters (n = 1,883 to 54,174) and to investigate whether a plateau in response for BA occurred. Line 2 (L2) was selected for an index of ovulation rate and embryo survival (G0 to G11), fully formed pigs (FF) per litter (G12 to 14), …

Comparative Digestibility By Cattle Versus Sheep: Effect Of Forage Quality, S. A. Soto-Navarro, R. Lancaster, C. Sankey, B. M. Capitan, B. P. Holland, L. A. Balstad, C. R. Krehbiel

Department of Animal Science: Faculty Publications

The objective was to determine the effect of forage quality on apparent total tract digestibility and ruminal fermentation in cattle versus sheep. Five yearling English crossbred (Hereford × Angus) steers (440.4 ± 35.6 kg of initial BW) and 5 yearling whiteface (Rambouillet × Columbia × Debouillet) wethers (44.4 ± 4.6 kg of initial BW), each fitted with a ruminal cannula, were randomly assigned to 1 of 3 forage sources within ruminant specie, and the study was conducted over 3 periods. For forage source, both animal and period served as the blocking factor with all forage sources represented once within each …

Effects Of Beef Production System On Animal Performance And Carcass Characteristics, C. L. Maxwell, C. R. Lopez, B. K. Wilson, B. T. Johnson, B. C. Bernhard, C. F. O'Neill, D. L. Vanoverbeke, G. G. Mafi, D. L. Step, C. J. Richards

Department of Animal Science: Faculty Publications

The objective of this study was to evaluate conventional (CONV) and natural (NAT) beef production systems from annual pasture through finishing through grazing. Beef steers (n = 180, initial BW = 250 ± 19 kg) were assigned randomly to 2 treatments in the pasture phase. Steers were implanted with 40 mg of trenbolone acetate (TBA), 8 mg estradiol, and 29 mg tylosin tartrate (CONV), or received no implant (NAT). Steers on the 2 treatments grazed wheat or cereal rye for 109 d. Conventional steers had an 18.5% improvement in ADG (1.22 vs. 1.03 kg/d, P < 0.01) and a heavier final BW (385 vs. 366 kg, P < 0.01) compared with NAT steers. Following the pasture phase, steers (n = 160 steers, 5 steers/pen, 8 pens/treatment) were assigned to a 2 × 2 factorial in the feedlot phase. Production system (NAT vs. CONV) was maintained from the pasture phase, and the second factor was 7 vs. 12% low-quality roughage (DM basis, LOW vs. HIGH). During finishing, CONV steers were given 120 mg of TBA and 24 mg estradiol at processing, fed monensin and tylosin, and fed zilpaterol hydrochloride for the last 20 d of the experiment. There were no program × roughage level interactions (P > 0.07). The CONV steers ate …

System And Method For Analyzing Properties Of Meat Using Multispectral Imaging, Jeyamkondan Subbiah, Chris Richard Calkins, Ashok Kumor Samal, Govindarajan Konda Naganathan

Department of Animal Science: Faculty Publications

A system and method for obtaining multispectral images of fresh meat at predetermined wavelength bands at a first time, subjecting the images to analysis in an image analysis system comprising a computer programmed to perform such analysis, and outputting a forecast of meat tenderness at a later point in time. Predetermined key wavelength bands are precorrelated with a high degree of prediction of meat tenderness and/or other properties of meat and are used in the multispectral system and method. A system and method for determining the key wavelengths is also disclosed. The multispectral imaging system and method is suitable for …

Western Immunoblotting In Avian Shell Gland Sample Immunoblotting Methods1, K.K. Hansen, R.J. Kittok, Gautam Sarath, Mary M. Beck

Department of Animal Science: Faculty Publications

Avian shell gland tissue was subjected to Western blot analysis using anti-human estrogen receptor- α antibody H222. Initial attempts to obtain consistent, high-quality blots were unsuccessful because, as it turned out, excessive lipid in tissue preparations interfered with protein separation. Incremental additions of acetone eventually proved to be the critical step in solubilizing lipids and allowing consistent separation of bands on gels. A detailed description of the methodology is presented.

Short-Term Effects Of Lower Oil Dried Distillers Grains With Solubles In Laying Hen Rations, Sheila E. Scheideler, Kathy Hanford, Brett Kreifels

Department of Animal Science: Faculty Publications

Extraction of oil from dried distillers grains has become a common practice among US ethanol producers. The valuable oil has been diverted to markets other than poultry feed, leaving new dried distillers grains with solubles (DDGS) products higher in fiber and purportedly lower in ME. This study compared 3 DDGS products with 10.3, 7.3, or 5.2% ether extract, respectively, with a corn-soy control ration in young Bovan laying hens for a feeding period from 20 to 33 wk of age. The DDGS was fed at the rate of 20% of the ration. Lower oil content of DDGS had no effect …

Use Of Robust Multivariate Linear Mixed Models For Estimation Of Genetic Parameters For Carcass Traits In Beef Cattle, S. O. Peters, K. Kizilkaya, D. J. Garrick, R. L. Fernando, E. J. Pollak, R. Mark Enns, M. De Donato, O. O. Ajayi, I. G. Imumorin

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Assumptions of normality of residuals for carcass evaluation may make inferences vulnerable to the presence of outliers, but heavy-tail densities are viable alternatives to normal distributions and provide robustness against unusual or outlying observations when used to model the densities of residual effects. We compare estimates of genetic parameters by fitting multivariate Normal (MN) or heavy-tail distributions (multivariate Student’s t and multivariate Slash, MSt and MS) for residuals in data of hot carcass weight (HCW), longissimus muscle area (REA) and 12th to 13th rib fat (FAT) traits in beef cattle using 2475 records from 2007 to 2008 from a large …

Beef Cattle Body Temperature During Climatic Stress: A Genome-Wide Association Study, Jeremy T. Howard, Stephen D. Kachman, Warren M. Snelling, E. John Pollak, Daniel C. Ciobanu, Larry A. Kuehn, Matthew L. Spangler

Department of Animal Science: Faculty Publications

Cattle are reared in diverse environments and collecting phenotypic body temperature (BT) measurements to characterize BT variation across diverse environments is difficult and expensive. To better understand the genetic basis of BT regulation, a genome-wide association study was conducted utilizing crossbred steers and heifers totaling 239 animals of unknown pedigree and breed fraction. During predicted extreme heat and cold stress events, hourly tympanic and vaginal BT devices were placed in steers and heifers, respect i v e l y. I n d i v i dua l s we r e genotyped with t h e BovineSNP50K_v2 assay and data …