Medicine and Health Sciences Commons^™

The Effects Of Omega-3 Pufa Infusions During Late Gestation On Developmental Pathologies In The Intrauterine Growth Restricted Fetus, Taylor Lacey

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

Low birthweight due to intrauterine growth restriction is associated with metabolic disorders after birth. Our 1^st study assessed deficits in skeletal muscle glucose metabolism and pancreatic β cell function in IUGR fetal sheep. We aimed to evaluate the effectiveness of daily intravenous infusions of the anti-inflammatory ω-3 polyunsaturated fatty acid (PUFA), eicosapentaenoic acid (EPA), as a means of improving deficits previously observed in the IUGR fetus by targeting fetal systemic inflammation. The presence of systemic inflammation in IUGR fetuses was evident by increased total circulating populations of total leukocytes, lymphocytes, and monocytes. However, these were …

Impact Of Beta-Adrenergic Agonist Supplementation And Heat Stress On The Microbiome And Gastrointestinal Transcriptome Of Sheep, Erin M. Duffy

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

Improving animal growth and efficiency are critical points of research as the world’s population and demand for agriculture products increase. Therefore, adaptions or changes in the gut are of interest to maximize growth efficiency and wellbeing of livestock. The gastrointestinal tract of the rumen plays many critical roles with the assistance of the associated microbial community. One way to improve animal performance is supplementation of β-adrenergic agonists (β-AA) which are commonly fed to cattle during the last 20-40 days of the finishing period, improving muscle growth by decreasing adipose deposition and increasing muscle accretion. Two β-AA, Ractopamine HCl (β1-AA) and …

The Role Of Inflammatory Pathways In Development, Growth, And Metabolism Of Skeletal Muscle In Iugr Offspring; Blood Gene Expression Of Inflammatory Factors As Novel Biomarkers For Assessing Stress And Wellbeing In Exotic Species., Robert J. Posont

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

Our first study identified the effects of maternal inflammation-induced intrauterine growth restriction (MI-IUGR) on growth and muscle glucose metabolism in offspring supplemented with curcumin. MI-IUGR lambs exhibited asymmetric growth restriction at birth and 30d of age, but normal glucose-stimulated insulin secretion. Hindlimb glucose oxidation was reduced by MI-IUGR and not improved by curcumin supplementation. Ex vivo muscle glucose oxidation was reduced by MI-IUGR but improved somewhat by curcumin. These finding indicate that fetal programming responses to MI contribute to neonatal growth and metabolic deficits. Neonatal curcumin supplementation had minimal effect on growth deficits but may improve glucose metabolism. …

Beef Cattle Management Systems For Estrus Synchronization And Heifer Development, Hazy Rae Nielson

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

Four experiments were conducted to evaluate estrus synchronization and heifer development systems. In the first experiment delaying AI 19 h following GnRH administration in a hybrid estrus detection and time AI protocol was evaluated. Final pregnancy rate was not different among heifers detected in estrus, AI at the time GnRH administration, or delayed AI. The second study compared the effect of melengestrol acetate (MGA) -PG and 14-d controlled internal drug release (CIDR) -PG estrus synchronization protocols on estrus response and pregnancy rates of 311 d old heifers. Final pregnancy rate was similar between CIDR and MGA treatment groups. The objective …

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 U.S. Meat Animal Research Center (USMARC). …

Genome-Wide Analysis Of The Variation In Host Genetics In Response To Experimental Challenges With Porcine Circovirus 2b, Taylor B. Engle

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

Porcine circovirus is the primary causative 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 lead to mortality. The variation in host genetics plays a role in the ability to initiate an effective immune response. The objective of this research was to identify major genetic variants and genes that influence immune response and PCVAD susceptibility. Commercial crossbred pigs (n=974) were experimentally infected with a PCV2b strain to analyze genetic sources of variation in PCVAD susceptibility. The strain used for experimental infection was …

The Role Of Sirtuin 1 And Ceramide In T10C12 Conjugated Linoleic Acid Induced Delipidation In 3t3-L1 Adipocytes, Wei Wang

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

Project 1: Trans-10, cis-12 conjugated linoleic acid (t10c12 CLA) reduces triglyceride (TG) levels in adipocytes through multiple pathways, with AMP-activated protein kinase (AMPK) generally facilitating, and peroxisome proliferator-activated receptor γ (PPARγ) generally opposing these reductions. Sirtuin 1 (SIRT1), a histone/protein deacetylase that affects energy homeostasis, often functions coordinately with AMPK, and is capable of binding to PPARγ, thereby inhibiting its activity. This study investigated the role of SIRT1 in the response of 3T3-L1 adipocytes to t10c12 CLA by testing the following hypotheses: 1) SIRT1 is functionally required for robust TG reduction; …

Maternal Obesity Alters Fetal Development Due To Impaired Placental Function And Has Lasting Effects On Adult Offspring, Kristin Ann Norwood

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

Obesity is an epidemic in many developed nations and maternal obesity can result in developmental alterations in offspring that have long-lasting effects. Two experiments were conducted to determine the impact of maternal obesity on placental development and early embryonic growth and muscle development. Experiment one utilized obese Lethal Yellow (LY) and normal weight C57BL/6 (B6) dams to assess how maternal obesity alters skeletal muscle development in mid-gestational embryos. Embryos from LY dams exhibited decreased embryo and placental weights as well as an increase in the myogenic marker desmin. Furthermore, the adipogenic marker PPARG expression was predominately localized to the neural …

Regulation Of Immediate Early And Epithelial-Mesenchymal Transition Genes Expression By Adipocytokines In The Female Reproductive Tract, Zhufeng Yang

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

Individuals who are overweight or obese are at increased risk for cancer. However, the mechanistic link between obesity and cancer is poorly defined. Adipose tissue produces hormones and pro-inflammatory cytokines with mitogenic properties. Many of these hormones and cytokines are altered in obese individuals and may lead to disruption of the normal balance between cell proliferation, differentiation, and apoptosis. Thus, the objective of this study was to determine how adipocyte-derived factors regulate the expression of genes that contribute to cell proliferation and migration. To compare immediate early gene (cell proliferation) and epithelial-mesenchymal transition (cell migration) gene expression between untreated and …