Life Sciences Commons^™

Effects Of Season And Nutrition On Insulinemic Responses In Insulin Dysregulated Horses, Erica Lyn Macon

Theses and Dissertations--Veterinary Science

Insulin dysregulation (ID) is the main risk factor for the development of hyperinsulinemia-associated laminitis (HAL). ID in the equid has been extensively researched; however, recommendations for diagnosing and managing ID horses have originated from work completed in other models, such as the ID pony and healthy horse. Therefore, our overall objective was to improve current diagnostic tools and nutritional management strategies by investigating the effect of season, the fed and fasted state on the oral sugar test (OST) and dietary nutrient content on insulinemic responses in the ID horse. To address this, four main objectives with three specific aims were …

Vole Population Dynamics In Cover Crops Transitioning To Soybeans With Integrated Pest Management By Habitat Modification, Jena L. Nierman

Theses and Dissertations--Forestry and Natural Resources

The use of cover crops has been a wildly used method in rotational row crop production. Cover crops have minimized soil runoff and aided in maintaining nutrients in agricultural fields. Increased use of cover crops has seen a corresponding increase in the amount of damage done to soybeans by voles. Currently, there are no mitigation methods that successfully decrease vole populations in agricultural fields. The use of habitat manipulation as an integrated pest management solution has not been studied as a practical solution for vole population management. During 2019 and 2020, I tested the impacts of various cover crop termination …

Muscle Mass And Immune Function In The Senior Horse, Alisa Christina Herbst

Theses and Dissertations--Veterinary Science

Senior horses (≥ 15 years) represent up to one-third of the global equine population, and the proportion of old horses (≥ 20 years) in the U.S. has been steadily increasing. Aging is associated with a loss of skeletal muscle mass in horses, and while age-related muscle loss is comparingly well characterized in humans, little is currently known concerning underlying mechanisms, adverse outcomes, or the prevalence of low muscle mass in senior horses. One factor proposed to play a role in the development of age-related muscle atrophy in humans is inflamm-aging, a low-grade inflammation that affects elderly people and that has …

Influence Of Dietary Manipulation On The Relationship Between Temperament Measures And Growth In Beef Cattle: Endophyte Exposure, Phytogenic Supplementation, And Controlled Feeding, Paul Shanks

Theses and Dissertations--Animal and Food Sciences

The influence of dietary factors (including endophyte exposure, phytogenic supplementation, and controlled feeding) on relationships between exit velocity (EV), growth performance in grazing and finishing cattle, and carcass characteristics were explored. Two grazing studies were conducted evaluating EV effects on cattle grazing both toxic and nontoxic endophyte-infected tall fescue. Cattle were followed through two subsequent finishing studies and an additional beef cattle finishing beef cattle study was also conducted. Results from these studies agree with many literature reports indicating that EV measures relate to growth performance and associated carcass traits in beef cattle being fed high energy diets in confinement, …

Arabinoxylan Structural Profiling Of Cool-Season Pasture Grasses Via High-Performance Anion-Exchange Chromatography With Pulsed Amperometric Detection (Hpaec-Pad) Analysis Of Endoxylanase Digests, Glenna Erin Joyce

Theses and Dissertations--Animal and Food Sciences

Arabinoxylan (AX) is a major structural polysaccharide found in the cell walls of monocots such as cereal grains and pasture grasses. The variety of AX structural components and substitution patterns contribute to AX structural diversity between different monocot species as well as plant tissues.

The rumen is the first digestion site of masticated food material in cattle and provides 70% of energy to host through fermentation of forage. There are many species of pasture grasses that act as a forage source. Differences in AX structure found in these pasture grasses may impact rumen microbial fermentation. Understanding the AX structure of …

Factors Influencing Mare Milk And Foal Gastrointestinal Health, Morgan Brewer Pyles

Theses and Dissertations--Animal and Food Sciences

Foals are born lacking a functional microbial community in their gastrointestinal tract (GIT). However, these microbes quickly colonize after birth. Factors influencing the process of microbial colonization and health of the foal’s gastrointestinal tract, such as milk yield and composition, are not well understood. Milk contains non-lactose carbohydrates termed “oligosaccharides”, which serve as prebiotics in human neonates and may serve a similar function in foals. Three animal studies were conducted to evaluate factors influencing mare milk and digestive health in the foal. In experiment 1, bacteria were enumerated and identified in foal feces and the utilization of different carbohydrates by …

The Effect Of Endophyte-Infected Tall Fescue Seed Consumption On Gut And Satiety Hormones Related To Intake Regulation In Holstein Steers, Mindy Elizabeth King

Theses and Dissertations--Animal and Food Sciences

Cattle consuming endophyte-infected tall fescue (E+) typically experience a syndrome termed fescue toxicosis which is thought to be caused by ergot alkaloids produced by the endophyte. The most abundant alkaloid, and considered the most likely cause of the syndrome, is ergovaline (ERV). During fescue toxicosis, a decrease in ADG is observed which is likely due to the decrease in DMI commonly observed in animals consuming E+ compared to animals consuming non-endophyte-infected tall fescue (E-). However, the cause of the decrease in intake is not well elucidated. Many physiological responses control feed intake including, but not limited to, physical, neural, metabolic, …

Isolation Box Test (Ibt) And Dairy Calf Personality Traits Relationship With Performance Through Weaning, Megan Marie Woodrum Setser

Theses and Dissertations--Animal and Food Sciences

Personality tests are utilized to characterize individual differences in personality traits across species. Currently, there is no objective personality test that can be implemented on-farm to measure personality in dairy calves. Measuring personality of youngstock in the dairy industry may allow producers to utilize information on individual differences for management decisions and limit the investment in unfit individuals. The isolation box test is a personality test that has potential to be adapted and utilized for dairy calves. The main objective of this thesis is to develop, validate, and utilize an isolation box test for use on-farm in dairy calves. More …

Impact Of Mineral Supplementation On Intake Behavior And Blood Flow In Growing Beef Cattle Exposed To Fescue-Derived Alkaloids, Hannah Marie Herzing

Theses and Dissertations--Animal and Food Sciences

Consumption of endophyte-infected tall fescue by cattle has repeatedly been shown to negatively impact dry matter intake (DMI), growth rate, and circulating prolactin concentrations. The objective of the current study was to determine if a mineral supplementation would mitigate the negative effects of fescue-derived alkaloid consumption on feed intake, circulating prolactin, and the vascular system. Twelve Angus crossbred steers were used in a triplicated Latin square design consisting of three 28 d experimental periods. Treatments consisted of three top-dressed mineral supplements (142 g/head/d): a non-medicated control (CON), commercially available Fescue EMT® Mineral Defense (EMT), and a test prototype (EMT 2). …

The Effect Of Oil Type, Oil Quality, Vitamin E, And Phytase Supplementation On Broiler Performance, Apparent Nutrient And Energy Utilization, And The Fatty Acid Profile Of Fat And Liver In Broiler Chickens, Richard A. Adefioye

Theses and Dissertations--Animal and Food Sciences

Two experiments were conducted to examine the effects of oil type, oil quality, phytase, and vitamin E (VE) supplementation in broiler chickens. Experiment 1 used 378-day-old male by-product Cobb breeder chicks with 9 treatments, 7 replicates, and 6 birds per replicate, structured as a 2x2x2+1 factorial arrangement of treatments for 14 days. The first 8 treatments were based on a marginally non-phytate phosphorus (NPP) deficient diet (0.31%), while treatment 9 was a positive control (PC) diet with adequate NPP levels (0.45%). There were 2 levels of phytase (0 vs 1000 FTU/kg), 2 levels of oil quality (fresh soy oil; peroxide …

Impact Of Feeding Foods Containing Industrial Hemp-Derived Cannabidiol On Canine Health And Well-Being, Elizabeth M. Morris

Theses and Dissertations--Animal and Food Sciences

Anecdotal evidence of beneficial behavioral and health effects of cannabidiol (CBD) use in companion animals has amplified the need to elucidate safety and potential impacts of CBD use. The purpose of this investigation was to determine the impact of industrial hemp-derived CBD administration on canine health and well-being. We hypothesized that CBD would produce beneficial effects on canine behavior without negatively impacting animal health. Dog treats were formulated to include CBD and shown to be palatable across a range of CBD inclusion levels. Dogs were supplemented with CBD treats and subjected to a noise-induced fear response test to assess potential …

Science-Based Regulation Of Pharmacological Substances In Competition Horses, Jacob Machin

Theses and Dissertations--Toxicology and Cancer Biology

Current testing methodologies within equine forensic toxicology focus on arbitrary thresholds and zero-tolerance policy. Modern analytical chemistry’s limits of detection are low enough that oftentimes femtogram-per-milliliter amounts of a substance can readily be identified in both blood and urine of a horse. For most pharmacologically relevant compounds, these concentrations have no relevance to pharmacological effect. It is therefore crucial that testing methodologies to determine appropriate thresholds and cut-offs be developed that are driven by biological activity rather than arbitrary limits of detection. This dissertation looks to address this by suggesting a system of calculated Effective Plasma Concentrations by which a …

Incorporation Of Summer Annual Mixtures Into Grazing Systems In Kentucky, Kelly Marie Mercier

Theses and Dissertations--Plant and Soil Sciences

Utilizing summer annual grass-legume forage mixtures has the potential to improve forage yield and nutritive characteristics, and/or animal performance during times when cool-season pasture growth is limited by high temperatures. Legumes can utilize atmospheric nitrogen, which can increase crude protein and forage digestibility in mixtures. As nitrogen application generally improves both the yield and nutritive characteristics of summer annual forages, but can have a negative effect on legume competitiveness, nitrogen fertilizer recommendations for legume-containing summer annual mixtures are not well established.

Two experiments were conducted to determine the feasibility of utilizing summer annual mixtures in Kentucky, USA. The first experiment …

Monocyte Abundance And White Blood Cell Expression Of Prolactin And Nf-Kb Pathway Genes In Beef Steers Are Altered By Grazing Toxic Endophyte-Infected Tall Fescue And Lipopolysaccharide Challenge, Cecilia Winfrey

Theses and Dissertations--Animal and Food Sciences

Experiment 1 tested the hypothesis that ad libitum consumption of a 1:1 blend (MIX) of sodium selenite (ISe) and SELPLEX vs solely ISe as selenium (Se) supplements (27 ppm) in a vitamin-mineral mix (V-M) by steers subjected to summer-long grazing of toxic endophyte-infected tall fescue (TE) would ameliorate the negative effects of TE by positively affecting the expression pattern of prolactin (PRL) and NF-kB pathway genes by circulating leukocytes (WBC). Experiment 2 tested the hypothesis that the MIX form of supplemental Se also would ameliorate the negative effects of in vitro blood lipopolysaccharide challenge (LPS) on WBC gene expression. The …

Distribution And Diversity Of Heliothine And Other Lepidopteran Nudiviruses, Emrah Ozel

Theses and Dissertations--Entomology

Helicoverpa zea nudivirus 2 (HzNV-2) is the only known sterilizing and sexually-transmitted insect virus and causes pathological symptoms in H. zea reproductive tissues. HzNV-2 has features that make it a candidate as a H. zea (corn earworm) control agent, such as the ability to cause asymptomatic (latent) and symptomatic (lytic) infections and the ability to influence mating behavior of its host to favor virus spread. HzNV pathology has been studied and its genome sequenced, however, its prevalence in natural populations is largely unknown. In this study, we developed and used a low-cost PCR-based molecular survey to investigate HzNV-2 prevalence and …

Modeling Energy Flows In Floating In-Pond Raceways Utilizing Solar Power Back-Up, Bo Smith

Theses and Dissertations--Biosystems and Agricultural Engineering

The In-pond Raceway (IPR) is a novel option for production aquaculture, depending on water moving devices to provide constant flow. Device failure may result in catastrophic fish loss, requiring power backup systems to mitigate risk in case of power outages. Because these systems must be dependable and many suitable locations are remote, off-grid solar photovoltaic (PV) systems with battery storage have been considered since they eliminate need for utility power. Such systems can be hard to size and expensive. This study modeled system requirements using an energy balance to determine whether systems could withstand varying loads based on climatological conditions. …

Pharmacokinetics And Reward-Related Behaviors Of Ethanol In Male And Female Japanese Quail (Coturnix Japonica), Shannon Eaton

Theses and Dissertations--Psychology

Ethanol is one of the most widely used and abused drugs. Problem use is associated with many different health problems and the economic burden is in the billions of dollars. Additionally, many people have difficulty controlling their ethanol consumption and about 5% of adults end up with an alcohol use disorder (AUD). Many people with an AUD often find themselves in a cycle of binge, remission, and relapse.

Following ethanol consumption ethanol enters the bloodstream from the small intestine where it gets distributed to peripheral tissues. Ethanol in the bloodstream is cleared from the system by the liver. The primary …