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Three Essays On The U.S. Beef Supply Chain: Production, Marketing, And Price Dynamics, Erdal Erol

Theses and Dissertations--Agricultural Economics

This dissertation contains three essays on select economic components of the U.S. beef industry. The first and second essays concentrate on the different economic problems in beef cattle production. The third essay evaluates the price dynamics and the impact of COVID-19 along the beef supply chain.

The first essay explores the economics of culling decisions in cow-calf operations in the U.S. with a novel application of a dynamic mathematical programming model. The results provide an optimal culling strategy under the base model and a range of optimal strategies that vary with respect to different components such as fertility probabilities, market …

Use Of Molecular Genetics To Investigate Population Structure And Swayback In Horses, Navid Yousefimashouf

Theses and Dissertations--Veterinary Science

The present research incorporated molecular genetic methods to 1) investigate the genetic basis of Juvenile Onset Lordosis or Swayback in the American Saddlebred horses; and 2) conduct a population genetic study to compare the Persian Kurdish, Persian Arabian and American Thoroughbred horse populations.

Juvenile-onset lordosis, or swayback, is a condition in horses where the conformational topline back curvature drops significantly within the first two years of life. The trait has a higher prevalence in Saddlebreds (5%). Prior research on them quantified the trait using a Measurement of Back Contour (MBC), defining an MBC of >7.0 centimeters as swayback, and8.0) MBC …

Age- And Sex-Dependent Alterations In Primary Somatosensory Neuronal Calcium Network Dynamics During Locomotion, Sami L. Case

Theses and Dissertations--Pharmacology and Nutritional Sciences

Over the past 30 years, the calcium (Ca2+) hypothesis of brain aging has provided clear evidence that hippocampal neuronal Ca2+ dysregulation is a key biomarker of aging. Indeed, age-dependent Ca2+-mediated changes in intrinsic excitability, synaptic plasticity, and activity have helped identify some of the mechanisms engaged in memory and cognitive decline. However, much of this work has been done at the single-cell level, mostly in slice preparations, and in restricted structures of the brain. Recently, our lab identified age- and Ca2+-related neuronal network dysregulation in the cortex of the anesthetized animal. Still, investigations in the awake animal are needed to …

Increasing Efficiency Of Finishing Beef Production: Strategies To Optimize Starch Digestion, Improve Flake Quality, And Reduce Methane Emissions, Ronald J. Trotta

Theses and Dissertations--Animal and Food Sciences

To continue to meet the demands of increasing food production and environmental sustainability, new strategies are needed to enhance the efficiency of finishing cattle production. A review of the literature identified several nutritional and physiological constraints that limit the ability for cattle to digest starch and absorb glucose from the small intestine. Comparative sequencing analyses revealed a missing region of the sucrase-isomaltase protein which could affect the capacity for starch digestion in cattle. Post-flaking sampling and handling recommendations were generated based on a series of experiments to improve estimates of starch availability and flaking consistency for commercial feedlots and laboratories. …

Selenium Form-Induced Changes In The Early Luteal Phase Corpus Luteum, The Blood, And The Endometrium During Early Gestation In Beef Cows, Sarah Nancy Carr

Theses and Dissertations--Animal and Food Sciences

Selenium (Se) deficient soils and thus forages are widespread throughout the United States, necessitating supplementation of this trace mineral in the diet of grass-fed cattle to negate detrimental effects of a deficiency on immune function, growth, and fertility. Conventionally, Se is supplemented to cattle in a vitamin-mineral mix as an inorganic form (ISe) although the organic forms (OSe) are available when cattle consumer forage, and OSe has been shown to increase the bioavailability of Se in cattle. Previous research has demonstrated supplementation with 1:1 mixture (MIX) of ISe and OSe compared to ISe alone increases systemic concentrations of progesterone (P4) …

Management And Characterization Of Root-Knot Nematode (Meloidogyne Spp.) In Kentucky High Tunnels, Victoria Bajek

Theses and Dissertations--Plant and Soil Sciences

Kentucky is one of the most active adopters of high tunnels in the United States. Across the state, high tunnel growers have reaped the benefits of greater marketable yields, season extension, and protection from harsh weather. However, the high tunnel environment has increased soil temperatures and intensive crop production which has the potential to encourage root-knot nematode (RKN; Meloidogyne spp.) infestations. The extent and distribution of RKN in Kentucky were previously unknown. Two on-farm trials in infested high tunnels were conducted to determine whether grafting with RKN-resistant tomato rootstock is a viable management strategy. A statewide soil census to determine …

Exploring The Effects Of Environmental Factors On Rice Blast Disease, April Ellen Lamb

Theses and Dissertations--Plant Pathology

Rice blast disease, caused by the ascomycete fungus Magnaporthe oryzae, occurs in over 85 countries and results in an annual crop loss of 10-30%, a corresponding nutrient value of meals for 60 million people. As a result, it is listed as a critical plant disease by the United Nations. Understanding factors affecting disease severity is of critical concern for food security. M. oryzae has been used as a model system for studying effector-triggered immunity (ETI) by understanding that ETI is primarily a plant response. M. oryzae has been used as a model to study fungal pathogenicity, host specificity, genome …

Placing The Evolutionary History Of Desmognathus Salamanders In Context: A Phylogeographic Approach, Kara Jones

Theses and Dissertations--Biology

Patterns of genetic variation do not arise in a vacuum but are instead shaped by the interplay between evolutionary forces and ecological constraints. Here, I use a phylogeographic approach to examine the role that ecology played in lineage divergence in the Desmognathus quadramaculatus species complex (Family: Plethodontidae), which consists of three nominal species: D. quadramaculatus, D. marmoratus, and D. folkertsi. Previous phylogenetic studies have shown that individuals from these species do not form clades based on phenotype. My approach to reconciling phylogenetic discordance was two-fold, using (1) genome-wide markers to provide insight into the …

The Relationship Of Multidimensional Athlete Characteristics Versus Competition Performance And Participation In American Football Players, Alex Brownell

Theses and Dissertations--Kinesiology and Health Promotion

BACKGROUND: Athlete evaluation in American football is dominated by the evaluation characteristics that underly key performance indicators (KPI’s) in the physical domain of performance. Team sport athlete performance is comprised of a combination of attributes in the physical, technical, tactical, and mental domains of performance. Using only KPI’s in the physical domain of performance to predict competition performance of American football athletes is challenging due to the differences in performance outcomes of the varying positions in American football and absence of the other performance dimensions that are not accounted for. Advances in athlete assessment have revolutionized the process of evaluating …

Effects Of Traumatic Brain Injury On The Intestinal Tract And Gut Microbiome, Anthony Desana

Theses and Dissertations--Physiology

Traumatic brain injury (TBI) initiates not only complex neurovascular and glial changes within the brain but also pathophysiological responses that extend beyond the central nervous system. The peripheral response to TBI has become an intensive area of research, as these systemic perturbations can induce dysfunction in multiple organ systems. As there are no approved therapeutics for TBI, it is imperative that we investigate the peripheral response to TBI to identify targets for future intervention. Of particular interest is the gastrointestinal (GI) system. Even in the absence of polytrauma, brain-injured individuals are at increased risk of suffering from GI-related morbidity and …

Rewired Metabolism In Apoe4 Microglia: Implications For Inflammation And Neurodegeneration, Nicholas A. Devanney

Theses and Dissertations--Physiology

Among the earliest changes to occur in Alzheimer’s disease, metabolic dysfunction and chronic neuroinflammation are now known to be major driving forces in disease progression. The paradigm of ‘immunometabolism’ seeks to bridge these two facets, positing that metabolic transformations are indispensable in determining the response of immune cells, such as microglia – the brain’s resident immune population. Proinflammatory stimulation of microglia leads to a shift away from mitochondrial respiration towards a dramatic upregulation of the glycolysis pathway for energy production. This glycolytic burst provides microglia with a rapid supply of ATP, but comes at a cost, as utilizing glucose to …

Characterization Of The Function And Regulation Of The Hmpv Phosphoprotein, Rachel Thompson

Theses and Dissertations--Molecular and Cellular Biochemistry

Human metapneumovirus (HMPV) is a non-segmented, negative strand RNA virus (NNSV) that frequently causes respiratory tract infections in infants, the elderly, and the immunocompromised. Despite the initial identification of HMPV in 2001, there are currently no FDA approved antivirals or vaccines available. Therefore, understanding the mechanism of HMPV replication is critical for the identification of novel therapeutic targets. A key feature in the replication cycle of HMPV and other NNSVs is the formation of membrane-less, liquid-like replication and transcription centers in the cytosol termed inclusion bodies (IBs). Recent work on NNSV IBs suggests they display characteristics of biomolecular condensates formed …

The Development And Characterization Of Nanobodies Specific To Protein Tyrosine Phosphatase 4a3 (Ptp4a3/Prl-3) To Dissect And Target Its Role In Cancer., Caroline Smith

Theses and Dissertations--Molecular and Cellular Biochemistry

Protein Tyrosine Phosphatase 4A3 (PTP4A3 or PRL-3) is an oncogenic dual-specificity phosphatase that drives tumor metastasis, promotes cancer cell survival, and is correlated with poor patient prognosis in a variety of solid tumors and leukemias. The mechanisms that drive PRL-3’s oncogenic functions are not well understood, in part due to a lack of research tools available to study this protein. The development of such tools has proven difficult, as the PRL family is ~80% homologous and the PRL catalytic binding pocket is shallow and hydrophobic. Currently available small molecules do not exhibit binding specificity for PRL-3 over PRL family members, …

Competition And Herbivory Influence The Survival, Growth, And Physiology Of Native Tree Seedlings In The Kentucky Inner Bluegrass Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Terrestrial plant communities are shaped by competition for resources, herbivory, and abiotic processes. Savanna systems represent a dynamic coexistence of contrasting life forms (grasses and trees) shaped by competition and disturbance. The Kentucky Inner Bluegrass Savanna-Woodland (KIBSW) is described as an open woodland of shade intolerant species; however, climatic, and edaphic conditions can support closed-canopy forest. After European pioneer settlement (c1750-1800), over 99% of “savanna-woodlands” have been lost. KIBSW remnants are experiencing a recruitment failure, leading to a dominance shift in tree communities. I researched how tree-grass competition and mammalian herbivory influence KIBSW regeneration and maintenance. The KIBSW does not …

Variation In Behavioral Strategies For Coping With Environmental Uncertainty, Allison Mclaughlin

Theses and Dissertations--Biology

My dissertation investigates how animals behaviorally respond to environmental change, especially when there is limited information about that change. Uncertainty about the environment comes in various forms, including food resources which vary unpredictably and novel cues which present an unknown level of potential risk or benefit. Various behavioral strategies help animals cope with such uncertainty. Tactics to manage unpredictable variation in food include gathering information to reduce uncertainty (sampling) and strategically adjusting preference or aversion to variation in resources (variance-sensitivity). To manage the uncertainty of a novel cue, animals may generalize their previous experience with similar cues, or they may …

The Long-Term Effects Of Wildfire Severity On Oak-Pine Communities And Their Microclimates, Scott Glenn Culbert

Theses and Dissertations--Forestry and Natural Resources

In the eastern U.S., fire-dependent tree species have historically dominated upland forest communities, but are now experiencing widespread regeneration challenges as a result of 20^th century fire suppression policies, and are being replaced by mesophytic species. Wildfires that contain areas of high burn severity may provide an important means of mitigating these challenges and facilitating fire-dependent species regeneration and recruitment into larger size classes. One mechanism by which high-severity fire can accomplish this is by modifying understory microclimate characteristics to be more conducive to these species’ growth. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided the …

Pond-Breeding Amphibian Responses To Wetland Creation And Reforestation On A Legacy Surface Mine In The Monongahela National Forest, Lauren Breanna Sherman

Theses and Dissertations--Forestry and Natural Resources

Surface mine reclamation has been an evolving practice since the Surface Mining Control and Reclamation Act was passed in 1977, holding mining companies accountable for returning ecological function to areas directly impacted by mining activities. One recent method of reclamation, the Forestry Reclamation Approach (FRA), aims to enhance reforestation and ecosystem function through the creation of wetlands, as opposed to traditional methods that often revert land to grasslands. However, wildlife response to FRA has rarely been investigated. The goal of this project was to analyze the effects of the four treatment types, FRA in two chronosequences, natural regeneration, and unmined …

A Characterization Of Key Residues In Class I Viral Fusion Proteins Important For Fusogenic Activity, Hadley E. Neal

Theses and Dissertations--Molecular and Cellular Biochemistry

Viral fusion proteins are critical for viral entry and subsequent infection. Class I fusion proteins are characterized by synthesis as an inactive precursor requiring cleavage by a host cell protease to become fusion competent. Though vaccine and antiviral therapeutic developments often target the fusion protein, questions surrounding cleavage dynamics and protein stability remain. The work presented in this dissertation investigates specific regions of three class I viral fusion proteins in an effort to identify key residues involved in proteolytic processing and membrane fusion.

The trimeric severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein (S) mediates receptor binding, facilitates fusion …

Effects Of Biosynthesized Bromoform On Enteric Methane Production, Animal Performance And Tissue Residues In Cattle, Sydney Davis

Theses and Dissertations--Animal and Food Sciences

Greenhouse gas (GHG) emissions have been implicated in global warming and extreme climate change conditions. The Environmental Protection Agency (EPA) has identified agriculture, more specifically cattle production, as a major contributor to global GHG production. When expressed as liters of gas, CO2 is considered the primary GHG produced, however, in terms of global warming potential (GWP), CH4 has 25-times greater potential than that of CO2. Due to the elevated GWP of CH4, we have constructed a series of experiments to investigate the use of a halogenated CH4 analogue derived from kelp (i.e., bromoform) as an inhibitor of enteric CH4 production …

Personality Traits Of Dairy Calves And Their Relationship With Feeding Behavior, Activity, And Performance, Emily A. Michalski

Theses and Dissertations--Animal and Food Sciences

Detection of individual differences in personality traits of animals may prove beneficial for producers to help tailor management for individuals and to make selection decisions. Therefore, the objectives of this thesis were to

1) review and evaluate literature on relationships between individual cattle personality traits and feeding behavior, activity, and performance; and

2) evaluate and develop tests suitable for characterizing crossbred dairy-beef calves’ personalities and associations with behavioral patterns and performance.

The existing literature indicates that growth, intake, activity, and milk production measures from precision technologies have associations with cattle personality traits and behaviors identifiable through standardized tests. This indicates …

Evaluation Of Boron Supplementation In Swine And Poultry, Tyler B. Chevalier

Theses and Dissertations--Animal and Food Sciences

The objectives of this dissertation were to evaluate dietary boron (B) supplementation as sodium borate in various swine models and broiler chicks through a series of experiments. The initial experiment evaluated supplemental B (0, 25, 50, and 100 ppm B) on serum insulin, glucose, and clinical chemistry panel of growing pigs. Serum insulin/glucose ratio tended to decrease linearly with increasing supplemental B in a fasting state (P = 0.08). These findings were more noticeable (linear effect, P = 0.02) in a postprandial state (~ 50 minutes following a meal). A series of follow-up studies further evaluating B supplementation (0, 5, …

Evaluation Of Increasing Levels Of Mycotoxin-Containing Corn Fines On Diet Choice And Growth Performance Of Nursery Pigs, Duncan B. Paczosa

Theses and Dissertations--Animal and Food Sciences

Pigs fed mycotoxin contaminated diets at high concentrations will result in a detriment to health and performance. An initial study and a follow-up study were conducted to evaluate the effects of feeding increasing levels of mycotoxin-containing corn fines on growth performance, diet preference of pigs, and two possible mitigants.

The initial study was a 3 x 2 factorial containing three levels of fines (0, 10, and 20%, Diets 1-3, respectively) and either 0 ppm (Diets 1-3) or 40 ppm boron (Diets 4-6; Diets 4-6 were Diets 1-3, respectively, plus boron) as sodium tetraborate decahydrate as a possible mitigant. In this …

Utilizing Precision Technologies To Validate A Real-Time Location System For Dairy Cattle And Monitor Calf Behaviors During Heat Stress, Emily Rice

Theses and Dissertations--Animal and Food Sciences

With the increase in on-farm precision dairy technologies (PDT) utilization, large quantities of information are readily available to producers. A more recently available technology for use in livestock species is the real-time location system. These technologies offer dairy producers the opportunity to monitor and track real-time locations of cows, track locomotion patterns, and summarize specific area usage. However, the usefulness of these insights is heavily dependent on the performance of the technology. Therefore, the first objective of this dissertation was to assess the positioning recording performance and the usefulness of the data recorded of a real-time location system (Smartbow GmbH; …

Profiling The Cell Wall Polysaccharides Of Hemp (Cannabis Sativa L.) Inflorescence And Hempseed And Exploring Their Application As Ruminant Feed Ingredients, Miranda Agbana

Theses and Dissertations--Animal and Food Sciences

Hemp (Cannabis sativa L.) is used in the United States as a source of CBD oil, fiber, and grain. While hempseeds are consumed whole or as dehulled hemp hearts, hempseed oil is also a desirable seed oil in human nutrition. The process of collecting hempseed oil leaves behind hempseed cakes that are abundant in protein and fiber. Feeding of hempseed cakes to animals, including ruminants, has only initially been explored. Extraction of CBD from hemp inflorescences generates organic waste that may find a second purpose as a fiber feed for cattle. Little is known about the exact fiber composition …

The Effects Of Exogenous Enzyme Supplementation On The Performance, Bone Quality, And Nutrient Utilization Of Broiler Chickens, Megan Bauer

Theses and Dissertations--Animal and Food Sciences

Two experiments were conducted to examine the effects of Allzyme® Spectrum supplementation to a reduced nutrient diet on the growth performance, energy and nutrient digestibility and utilization, bone quality, and jejunal digesta viscosity in broiler chickens. Each experiment used 300 one-day old Cobb by-product breeder chicks with 5 treatments, 10 replicates, and 6 birds per replicate cage in a randomized complete block design. The only differences between the two experiments were experiment 1 lasted for 21 days using a corn-soybean meal-based diet and experiment 2 lasted for 22 days using a wheat-soybean meal-based diet. The 5 treatments included a positive …

Precision Livestock Farming And Personality As Tools To Understand Dairy Calf Individual Variation In Performance, Behavior, And Response To Stress, Megan Marie Woodrum Setser

Theses and Dissertations--Animal and Food Sciences

Individual differences impact animal responses to their environments and can be observed with animal personality (stable behavioral differences with populations) and food neophobia (avoidance of unfamiliar feeds). These individual differences can influence cattle performance and welfare. Precision technologies, such as automatic feeding systems (AFS) and accelerometers continuously measure feeding behaviors and activity and may allow us to relate individual differences to behaviors in the home environment. Therefore, the first objective was to determine if food neophobia was associated with feeding behaviors measured by AFS. Food neophobia was associated with rewarded visits to the AFS, but to no other feeding behaviors. …

Developing A Biocatalytic Toolbox To Aid In Understanding Nucleoside Antibiotics, Jasmine Brianna Woods

Theses and Dissertations--Pharmacy

Antibiotic resistance happens when bacteria develop the ability to survive medications that normally terminate them. Instead, these super germs are able to survive in the body and produce a community of antibiotic resistance germs which can cause human fatalities. It is important to discover and develop new compounds and molecules that will improve this clinical obstacle. This research focused on analyzing the biosynthesis that incorporates distinctive chemical characteristic of various nucleoside antibiotics, ß-hydroxy amino acids and α-methyl-amino acids. ß-hydroxy amino acids and α-methyl-amino acids are considered an important class of industrially useful compounds, particularly for pharmaceutical development, and are found …

Therapeutic Implications Of The Gut-Cns Axis In Promoting Recovery Following Cervical Spinal Cord Injury, Jessica Wilson

Theses and Dissertations--Neuroscience

Nearly 60% of all spinal cord injuries (SCI) occur at the cervical level. These high-level injuries can interrupt the descending respiratory pathways required for breathing. Indeed, therapies in animal studies have been successful at restoring breathing after SCI; however, these interventions appear to be more effective at chronic time points. One potential cause for this observation is the impact of the injury on the gut microbiome. Neurotrauma can induce gut dysbiosis, an imbalance of pathogenic and beneficial gut microbiota, which has previously been shown to negatively impact the central nervous system (CNS) and impair recovery. We aimed to build upon …

Landscape Influences And Preventive Management For Drosophila Suzukii In Small Fruit Crops, Ryan William Kuesel

Theses and Dissertations--Entomology

Small fruit production has been greatly challenged by the repeated invasion of non-native arthropod pests, impacting economic feasibility, and increasing the need for insecticides. Spotted wing drosophila (Drosophila suzukii (Matsumura)) is the most recent invasive pest of small fruits. It causes damage by ovipositing beneath the skin of ripening fruits. Its wide-spread distribution and development of resistance to insecticides has resulted in the need for improved alternative management strategies for small fruit growers.

My surveys of D. suzukii at thirteen blackberry (Rubus fruticosus L.) and raspberry (Rubus idaeus L.) fields found that while D. suzukii was present …

Effect Of Menstrual Cycle Phase On The Rewarding Properties Of Alcohol In Women, Annie K. Griffith

Theses and Dissertations--Psychology

Compared with men, women are disproportionately affected by alcohol, including greater risks of behavioral impairment and relapse. One likely mechanism underlying this disparity is fluctuations of ovarian hormones, particularly estradiol (E2), across phases of the menstrual cycle. Pre-clinical and clinical studies have shown that higher E2 levels correlate with heavier patterns of alcohol consumption, suggesting E2 may modulate drinking. This relationship is thought to be mediated by the rewarding properties of alcohol. The present thesis tested the hypothesis that elevated E2 during the late follicular phase would increase the rewarding properties of alcohol. Fifty young-adult women participated in a within-subjects …