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Full-Text Articles in Life Sciences
Heat Stress Changes The Bovine Methylome And Transcriptome And Investigation Of Two Novel Genetic Defects In Cattle, Rachel Renae Reith
Heat Stress Changes The Bovine Methylome And Transcriptome And Investigation Of Two Novel Genetic Defects In Cattle, Rachel Renae Reith
Department of Animal Science: Dissertations, Theses, and Student Research
Heat stress is a major concern for livestock producers due to its negative impact on animal health and productivity. Heat stress does so by altering expression of genes through different regulatory mechanisms such as DNA methylation. Understanding how heat stress alters gene expression will help elucidate the genetic basis of physiological changes as well as identify targets for possible heat stress mitigation. The purpose of the first study was to understand how heat stress alters the adipose and skeletal muscle transcriptomes in zilpaterol-fed Brahman, as zilpaterol improves muscle growth and may mitigate the effects of heat stress. Differential expression and …
Investigation Of Breeding Objectives And Indexes-In-Retrospect, Hunter F. Valasek
Investigation Of Breeding Objectives And Indexes-In-Retrospect, Hunter F. Valasek
Department of Animal Science: Dissertations, Theses, and Student Research
This thesis presents two projects that investigate the impacts of breeding objectives and indexes-in-retrospect within the beef cattle industry. The first project synthesized how changes due to planning horizon, breeding system, and sale endpoint in the economic breeding goal of cattle influence the relative emphasis of traits as well as the re-ranking of selection candidates. A total of three breeding systems that represent straightbred and crossbred cattle were used along with six planning horizons (2, 5, 10, 20, 30, and 50 yrs.) for both a weaning and slaughter point of sale. The combination of these different breeding objective attributes resulted …
Identifying Breed Effects For Cow Mature Weight, Madeline J. Zimmermann
Identifying Breed Effects For Cow Mature Weight, Madeline J. Zimmermann
Department of Animal Science: Dissertations, Theses, and Student Research
Mature weight (MWT) in beef cattle has increased over the past 30 yr. In general, larger cows are costlier to maintain than smaller cows, and their profitability depends on their production environment. A wide range of beef production environments exist in the United States. There are also a variety of beef cattle breeds that can be chosen and mated to create a type of cow which will be optimally suited to excel in a given environment. However, there remains a need for tools allowing effective comparison among breeds to facilitate such decision making. Unfortunately, estimated progeny differences ( …
Evaluation Of Alpha Amylase Containing Corn On Finishing Cattle Performance And Digestibilty, Melissa L. Jolly-Breithaupt
Evaluation Of Alpha Amylase Containing Corn On Finishing Cattle Performance And Digestibilty, Melissa L. Jolly-Breithaupt
Department of Animal Science: Dissertations, Theses, and Student Research
One digestion and four finishing trials were conducted to evaluate the effect of a new corn hybrid containing an α-amylase trait, Syngenta Enogen Feed Corn (SYT-EFC) on site and extent of digestion, ruminal fermentation parameters, and feedlot performance. Experiments utilized corn containing the enzymatic gene compared to controls, the near isoline parental corn (NEG) or commercially available corn grain (CON), processed as dry-rolled corn (DRC) or high moisture corn (HMC) in diets with dry [distillers grains plus solubles (DGS)] or wet (Sweet Bran) milling byproducts. The corn grain of the experimental diets were fed as the sole grain source, comprising …
Construction Of A Pen-Scale Methane Collection System And Dietary Strategies For Methane Mitigation From Growing And Finishing Cattle, Thomas Winders
Construction Of A Pen-Scale Methane Collection System And Dietary Strategies For Methane Mitigation From Growing And Finishing Cattle, Thomas Winders
Department of Animal Science: Dissertations, Theses, and Student Research
Methane production from ruminants has been researched for many years because it has a global warming potential 25x that of carbon dioxide, meaning that mitigating smaller amounts of methane can have a large environmental impact. Research has focused on individual animal methane measurements, but the literature lack in industry-scale measurements. For that reason, the methane barn was built to evaluate dietary strategies on pens of cattle rather than on individual animals. In order to test the methane barn capabilities, an experiment designed to produce differences in methane production was conducted. Cattle received the same growing diet, at either ad-libitum access …
Supplementation And Reproductive Strategies For Beef Females As Part Of A May-Calving Herd In The Nebraska Sandhills, Alicia Caitlin Lansford
Supplementation And Reproductive Strategies For Beef Females As Part Of A May-Calving Herd In The Nebraska Sandhills, Alicia Caitlin Lansford
Department of Animal Science: Dissertations, Theses, and Student Research
The objective of these 4 studies was to evaluate the effects of management decisions on reproductive performance of beef females. Experiment 1 evaluated the efficacy of a novel s.c. prostaglandin F2a injection on estrus synchronization and pregnancy success in yearling beef heifers. Heifers receiving a 2 mL s.c. injection of Lutalyse HighCon had similar estrus response and pregnancy rates compared to 5 mL Lutalyse i.m. within 2 different estrus synchronization programs. In experiment 2, May-calving heifers and primiparous cows were allotted to receive either no supplementation or supplement (0.45 or 0.91 kg/d per animal, heifers or primiparous cows, …