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The Evaluation Of Broiler Lines Divergently Selected For Water Conversion Ratio Under Acute And Chronic Stress, Baileigh B. Cash

Poultry Science Undergraduate Honors Theses

            The importance of water conversion ratio in broiler production influences not only bird physiology but also barn environment, litter quality, and provides potential solutions to environmental stressors. However, very little is known about how genetic selection for water conversion ratio can affect litter characteristics and performance parameters, specifically under heat stress conditions. This study evaluates the effects of genetic lines, environmental conditions, and time, on litter and bird performance characteristics in high water conversion ratio (HWCR) and low water conversion ratio (LWCR) broilers. Litter samples were collected from HWCR and LWCR broilers raised under heat-stress and thermal-neutral conditions, both before …

Mammalian Biodiversity Of The Easley Conservation Stewardship Area, Grayson C. Belt

Honors College Theses

Monitoring wildlife is an important part of conservation and is particularly vital for newly acquired conservation areas to provide a baseline of what is present. In 2025, the 22 ha Murray State University Easley Conservation Stewardship Area (MSU ECSA) was established following a donation to the university by Melissa Easley. I conducted a survey using trail cameras at the ECSA in fall 2025 and winter 2025/26 to record mammalian diversity. The survey consisted of two subprojects: a mesomammal subproject of 18 knee height trail cams and a small mammal subproject using 15 custom small mammal bucket cameras. I uploaded all …

Effect Of 1,25(Oh)₂D₃ Glycoside Supplementation Duration On Bacterial Chondronecrosis With Osteomyelitis (Bco) Lameness In Broilers, Zoe R. Zeman

Animal Science Undergraduate Honors Theses

Bacterial chondronecrosis with osteomyelitis (BCO) is a significant cause of lameness in commercial broilers, resulting in substantial animal welfare concerns and economic losses. This study evaluated the effect of 1,25(OH)₂D₃ glycoside supplementation duration on the incidence of BCO-related lameness in broilers. Cobb surplus male broiler chicks were assigned to four treatment groups: a wire-flooring positive control, a litter-flooring negative control, and two treatment groups on litter flooring receiving 1 μg 1,25(OH)₂D₃ as glycosides supplementation per kg diet for either 14 or 28 days. Lameness incidence was recorded from day 22 through day 56, and all lame birds were evaluated for …

Effect Of A Probiotic Microbial Gel Jointly With Two Versions Of Supplemental Direct-Fed Microbials In Receiving Cattle Diets On Growth Performance And Health, John Mitchell

Biological Sciences Undergraduate Honors Theses

The objective was to assess the effect of a probiotic microbial gel (BIOFRESH® Microbial Gel, Agrarian Solutions) administered on arrival in combination with feeding one of two different direct-fed microbials (DFM 365a or DFM 365b, Agrarian Solutions) on the health and growth performance of stocker calves at high risk for bovine respiratory disease (BRD). Beef heifer calves (n = 292, BW = 476 ± 5 lb) arriving on 3 separate receiving dates were used in the 42-day receiving study. On arrival (d -1), heifers were processed, stratified by d -1 body weight, and then assigned randomly to 9 pens (10 …

Assessing The Conservation Needs Of Native Texas Crayfish Species Through Distribution Analysis And Species Distribution Modeling, Elizabeth J. Croft

Biology Theses

Crayfish have essential roles in ecosystems because they are ecosystem engineers and keystone species. However, crayfish species are threatened by degradation and loss of habitats, introduction of invasive species, and high levels of endemism. Texas provides no legal protections for crayfish, despite its large number of species and endemics in the state. The overall goal of this study is to clarify the distributions of native Texas crayfish species using literature records, citizens science, and field sampling data, and highlight species in need of more conservation research. Occurrence records from all collected data were combined to visualize the distributions of species …

The Effects Of Heat Stress On White Blood Cell Profiles And Antibody Concentrations In Broilers Genetically Selected For Low Water Conversion Ratio Compared To The Modern Random Bred Broiler, Luke B. Janski

Poultry Science Undergraduate Honors Theses

Heat stress (HS) is one of the most significant environmental stressors impacting poultry production worldwide, reducing growth, feed efficiency, welfare, and immune competence. With global temperatures rising, understanding physiological and immunological adaptations to HS is essential for sustainable production. Broiler chickens selectively bred for low water conversion ratio (LWCR) have shown potential for reduced water consumption under environmental challenges; however, their immune resilience under HS conditions compared with modern random-bred (MRB) broilers remains unclear. This study investigated the effects of cyclic HS on red- (RBC) and white- (WBC) blood cells and humoral immunity in LWCR and MRB broilers. Birds were …

A Series Of Investigations On The L. Cornutus Host System And Bivesiculid Sp. Cercariae, Briana K. Zaffiro

All HCAS Student Capstones, Theses, and Dissertations

Rising global temperatures are likely modulating parasite-host interactions, yet the direction and magnitude of these changes remain uncertain. Rarely are these interactions viewed from both a host and parasite perspective. Using both CT_max, or Critical Thermal Maximum, and Clark-type polarographic oxygen microelectrodes, the physiological metabolic effects are investigated. CT_max is examined in Common Shiners, Luxilis cornutus, and is shown to be modulated by parasitism: uninfected fish had the highest CT_max average of 37.0°C, whereas heavily infected fish had decreased CT_max averaging 35°C. Prior to the parasite metabolic investigation, a suitable medium was determined, as …

Environmental Enrichment Preferences And Play Behavior In Commercial Turkey Hens, Paul Dang

Poultry Science Undergraduate Honors Theses

Commercial turkey production contributes significantly to the U.S. agricultural industry, yet studies on positive welfare indicators, especially play behavior, are limited. This study evaluated turkey hen interactions with two environmental enrichments (straw bales and pecking stones hung from the ceiling) and the expression of play behavior in turkey barns. Three commercial turkey hen barns were equipped with environmental enrichments and time-lapse video cameras. Play behaviors were recorded during transect walks in two barns using 30-second scans of disturbed and undisturbed patches. Regional use of space around enrichments was quantified through region-of-interest (ROI) analysis of time-lapse images collected from days 16-31 …

Beat Behind The Bark: Investigating The Effects Of Music Tempo On Canine Physiological And Psychological States, Marley Lanier

Honors Theses

This study explores how the tempo of music, measured in beats per minute (BPM), affects dogs' heart rate and oxytocin levels, adding to past research that shows that music affects physiological and behavioral states in dogs. Being able to understand these effects holds practical implications for improving overall well-being in canines in environments such as homes, shelters, and clinical environments. Using a within-subjects design, the dogs were exposed to slow and fast versions of one instrumental track, along with a white noise baseline condition before each randomized condition. Heart rate was recorded continuously throughout the session, and oxytocin saliva samples …

Preserving The Past: Exploring The Last Frontier's Ecosystem Shifts And Biodiversity Of The Tallgrass Prairies, Gisell Maldonado, Amelia Villaseñor

Anthropology Undergraduate Honors Theses

In North America, grasslands are a cornerstone of the environment. Historically, the tallgrass prairie was expansive and reached from Manitoba in Canada to Texas. Today this unique ecosystem is highly fragmented and reduced, but it remains an important ecosystem for biodiversity and cattle management. While there are many complex ecological interactions in the prairie, recent research shows that large herbivores are vital in maintaining grasslands through grazing and other behaviors that reduce woody encroachment and support nutrient cycling. Here, we examine cow and bison dietary behaviors and connect these to the ecosystem services provided by these large herbivores. In the …

Influence Of Increased Supplementation Of Organic-Complexed Zinc To Beef Cows During Gestation: Effects On Preweaning Health Of Offspring, Naija N. Sharpley

Animal Science Undergraduate Honors Theses

The objective of this study was to determine the effect of increasing zinc supplementation from organic-complexed sources to beef cows during gestation on calf performance. In May 2025, during gestation, Angus crossbred cows were confirmed pregnant with female sexed semen (n = 83) and enrolled in the current study. Cows (4.7 ± 2 years of age and 531 ± 84.4 kg body weight, mean ± standard deviation) were allotted to 4 groups (20 to 21 cows/group) based on, sire of heifer calf, cow age, and cow body weights taken at weaning. Assigned groups received 1 of 2 treatments (2 groups/treatment): …

Companion Parrot Vocal Learning And Reproduction Of Human Speech Sounds, Karla Vilches Castaño

Master's Theses

Vocal learning is rare among animals but is well developed in parrots, which can imitate novel sounds and, in captive settings, reproduce human speech. This study helps address a larger evolutionary question about vocal learning. Specifically, whether vocal learning ability is best understood as a single generalized trait or as a multi-dimensional system in which different acoustic features can be learned and reproduced with varying degrees of fidelity. This thesis quantifies how closely companion parrots match their human tutors across three acoustic dimensions (spectrographic structure, intensity contour, and pitch contour) and tests whether mimicry accuracy varies among individuals, differs between …

Sorghum Grain Secondary Metabolites And Underlying Genetics To Reduce Foodborne Pathogens In Poultry, Maria A. Conti

All Dissertations

The rise in antibiotic-resistant pathogens poses a threat to the poultry industry's ability to maintain animal health, prompting growing interest in alternatives to synthetic antibiotics. The use of non-tannin sorghum [Sorghum bicolor (L.) Moench] in poultry rations offers a valuable alternative, as this cereal grain has a high bioactive profile that can provide health benefits, including antimicrobial (AM) activity. The scope of this study was to examine the AM potential of non-tannin sorghum grain against Clostridium perfringens, a major foodborne pathogen that negatively impacts poultry health and production. To that end, the inhibitory effects of a non-tannin sorghum …

Foraging Plasticity And Mercury Contamination In Red-Legged Kittiwakes: A Multiple Stressor Perspective, Sam E. Clay

All-Inclusive List of Electronic Theses and Dissertations

Arctic seabirds are facing increasing stress from climate change, yet the interactive effects of multiple stressors on behavior remain poorly understood. Adopting a multiple stressor perspective promises to advance understanding of avian behavioral responses to climate change, as climate change is exposing Arctic and subarctic animals to a complex set of stressors rather than a single stressor in isolation. Using the red-legged kittiwake (Rissa brevirostris) as a model, I examined how multiple stressors, including mercury (Hg) exposure, shifting wind conditions, and varying foraging conditions linked to sea surface temperature (SST) may interact to constrain behavioral plasticity and energetically expensive behavior …

The Beat Behind The Bark: Investigating The Effects Of Music Tempo On Canine Physiological And Psychological States, Marley Lanier

Poster Presentations

Music is a universal component of human culture that has been demonstrated influencing emotional, cognitive, and physiological responses, specifically heart rate and hormonal responses (Mehr et al., 2019; Trappe, 2012). Recently, this research has expended to explore how music may affect non-human animals, particularly dogs, due to their roles as therapy animals, service animals, and human companions (Lindig et al., 2020; Gee et al., 2021). Being able to understand how music influences canine stress and relaxation hold important applications in environments such as shelters, veterinary clinics, and at home. One important feature of music is tempo, or beats per minute …

Acute Effects Of The Psychoactive Pollutant Fluoxetine On The Antipredator Behavior Of The Gulf Killifish (Fundulus Grandis), Semyra Reus

Honors Theses

Pharmaceutical contaminants are increasingly prevalent in aquatic environments, yet their sublethal effects on ecologically relevant behaviors remain poorly understood, particularly in estuarine systems. Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine, are of particular concern due to the conserved role of serotonin in regulating behavior across vertebrates. Here, we investigated how acute exposure to environmentally relevant concentrations of fluoxetine influences anti-predator behavior in Gulf killifish (Fundulus grandis), a key estuarine fish commonly found in saltmarsh habitats. Killifish were exposed to control (0 ng/L), low (17.8 ng/L), and high (596 ng/L) fluoxetine concentrations and subsequently tested in the presence …

Improving Genomic Prediction For Feed Efficiency Traits In Beef Cattle Using Microbiome As An Intermediate Omics, Egodage Bhagya Sewwandi Samarakoon

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

Feed efficiency traits, including feed conversion ratio (FCR), average daily gain (ADG), and average daily dry matter intake (ADDMI), are economically important in beef cattle production. Emerging evidence suggests that host genetics influences feed efficiency traits through the microbiome. This study evaluates the integration of microbiome data as an intermediate layer in the Neural Network Mixed Model (NNMM), which hierarchically models genotype–microbiome–phenotype relationships as a unified regulatory network to improve genomic prediction accuracy. To reduce the computational burden of NNMM, microbiome features dimension were reduced using principal component analysis (PCA) and direct feature selection of top-ranked open reading frames (ORFs) …

Carcass Mass And Cooling Dynamics As Determinants Of Beef Color, Tenderness, And Dark-Cutting Risk, Grace C. Johnson

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

Discoloration in beef has important implications to the beef industry. Dark-cutting (DC) beef remains one of the most economically significant color defects; however, industry prevalence has only marginally declined (≈ 0.1%) despite mitigation efforts. This lack of improvement largely stems from research focused on pre-harvest stress and glycogen depletion leading to dark, firm, and dry (DFD) beef. However, not all darkcutting beef originates from DFD phenotypes. Atypical dark-cutting (ATDC) phenotypes have recently been observed and do not exhibit the classic metabolic indicators of DFD. This trend coincides with steadily increasing carcass weights in the beef industry and raises the possibility …

Monitoring Biodiversity Growth In An Oyster Reef Restoration: Understanding How Oyster Reef Life Cycle May Impact Biodiversity., Gabriel A. Roses

Theses and Dissertations

Oyster reefs are vital to marine ecosystem health, improving water quality and providing food and habitat for diverse species. We assessed biodiversity changes for a proposed oyster reef restoration site to help guide management, future assessment, and deepen understanding of how oyster reefs function and their ecosystems dynamics.

Lipid Deposition In Beef Cattle, Kyra L. Elliott

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

Both the amount and types of lipid deposition in beef cattle are key determinants of carcass value and meat quality. Amounts of intramuscular, subcutaneous, and visceral fat influence carcass grading outcomes, palatability, and composition traits that are important to beef producers as well as consumers. The objectives of this thesis were to: 1) compare beef grading camera estimates of intramuscular fat to amounts of chemically extractable lipid, 2) characterize the lipidomes of beef intramuscular fat, subcutaneous fat, and lean muscle using shotgun lipidomics, and 3) identify and characterize a novel genetic variant in cattle that may have important implications for …

Characterization Of Activity Changes In Gilts During Estrus Using The NuTrack Livestock Monitoring System, Emily P. Aquino

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

Early and accurate detection of estrus in replacement gilts is essential for reproductive success and to ensure efficient production. The objective of this study was to evaluate activity changes occurring relative to first estrus of gilts and subsequent cycles. At ~ 110 days of age, 112 gilts were randomly assigned to 14 pens and placed under continuous video monitoring until the end of the trial at ~ 200 days of age. Daily boar exposure (~ 10 minutes per day) began at ~ 122 days of age. During this period, recorded observations included vulva scores (based on swelling and redness), mounting …

Evaluation Of Maternal Bovine Appeasing Substance Administration And Feed Access Time On Finishing Cattle Performance, Behavior, And Carcass Characteristics, Carsten L. Loseke

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

Novel products and bunk management techniques may significantly influence economically relevant performance metrics of feedlot cattle. The objective of the first experiment was to evaluate maternal Bovine Appeasing Substance (mBAS) administration on performance, carcass, health, and cortisol outcomes of yearling steers. Steers (n = 1,754, initial BW = 423 kg, SD = 25 kg) were received and assigned to pens for treatment allocation. Steers received either 10 mL of the mBAS or a mineral oil placebo at initial processing and reimplant. Hair samples were collected from a subset (n = 4 steers/pen) on d 0 and d 14. …

Integrating Growth Performance And Pathogen Detection To Investigate Disease Resilience In Commercial Swine, Emmalise Hope Marie Meyer

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

Disease resilience is an important trait in commercial swine production, influencing both animal health and growth performance under natural disease challenge. The primary objective of this study was to integrate growth performance data with longitudinal pathogen detection to better understand factors contributing to disease resilience in commercial pigs. A population of 1,014 pigs across four batches was monitored from weaning through the grow-finish phase, with body weights collected to calculate average daily gain (ADG). Genome-wide association analyses were conducted using BayesC and BayesIM approaches to identify genomic regions associated with growth performance. Longitudinal pathogen surveillance was performed using pen-level oral …

Tail Biting In The Nursery: Evaluating Postural, Spatial, And Behavioral Differences Between Tail Biter And Victim Pigs, Storey L. Forster

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

This study examined behavioral differences among pigs classified as tail biters, victims, or neutral during the nursery period. A total of 192 undocked nursery pigs were assigned to eight pens and monitored for 30 days using the NUtrack system. Tail biting events were identified from video observations, and pigs contributing to the top 25% of observed tail biting activity were classified as tail biters. Based on weekly tail scoring, pigs assigned a maximum tail injury score ≥ 2 were classified as victims. All other pigs were considered neutral. A total of 700 tail biting events were observed. Thirty-eight pigs …

Application Of High-Pressure Processing To Improve The Color Of Dark Beef, Kara Ann Reynolds

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

Deviation of beef from the bright cherry-red color preferred by consumers is often discounted or discarded at retail, resulting in substantial annual economic loss to the beef industry. One such deviation is dark cutting beef, which is characterized by a darker lean appearance that is undesirable to consumers and often rejected. Similarly, beef from mature cattle tends to exhibit a darker surface color, which can also reduce consumer acceptability. High-Pressure processing (HPP) has been investigated as a strategy to improve the color of dark cutting beef. Previous studies have focused on identifying pressure levels and holding times that optimize color …

Factors Affecting The Efficacy Of Free Choice Vitamin & Mineral Supplementation Programs, Tanner K. Wansing

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

While free choice vitamin and mineral supplements are widely used within the cow/calf sector, large knowledge gaps exist around the proper management of those supplements. This thesis discusses two factors affecting the efficacy of supplementation. The first interest was the stability of vitamin A when stored with a common free choice mineral supplement. This research addressed a critical data gap by generating information on vitamin A stability within the beef industry, as current data are predominantly based in the swine industry. Vitamin A was discovered to be stable until 4 months of storage regardless of storage conditions, whereas after 4 …

Fisheries Management Paper No. 313: Western Australian Statewide Small Pelagic Scalefish Resource Harvest Strategy, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Management Papers

Harvest strategies for Western Australia’s (WA) aquatic resources are formal documents developed by the Department of Primary Industries and Regional Development (DPIRD, the Department) to support decision-making processes that ensure the outcomes are consistent with the principles of Ecologically Sustainable Development (ESD; Fletcher 2002a) and Ecosystem Based Fisheries Management (EBFM; Fletcher et al. 2012).

Harvest strategies are a key component of all contemporary fishery management systems and a requirement for certification under the Marine Stewardship Council (MSC; Marine Stewardship Council 2018). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA).

This Statewide …

Long Term Changes In Elk Group Size And Composition (2002-2023) In Relation To Wolf Hunting Sucess, Kennedy Price

Undergraduate Honors Capstone Projects

Elk (Cervus elaphus) in Yellowstone National Park exist within a predator-prey system shaped by long-term interactions with wolves (Canis lupus). This predator-prey system represents an important model for understanding how predation influences ungulate behavior and social organization. Predators affect prey behavior through direct and indirect interactions and may cause long-term changes. What this study strives to answer is if predator success can have long term effects on prey grouping behavior and age-sex structure. In a previous study, wolves were found to be most successful hunting medium sized group of elk (20-49 individuals) in Yellowstone National Park. …

The Hitchhiker's Guide To The Host: Fleas And The History Of Pikas In North America, Josh Pletcher

All NMU Master's Theses

Parasite phylogenetics can offer windows into the cryptic evolutionary history of hosts, often highlighting events that are not recorded by the phylogenetics of the host. Pikas (small lagomorphs) host a diverse parasite community comprising endoparasites (e.g., coccidians, nematodes, and cestodes) and ectoparasites (e.g., fleas and mites). Phylogenetic analysis of pika endoparasites has revealed pikas evolved in Asia and colonized North America in two waves, and that contact between these two pika lineages allowed parasites to be transferred from one lineage to another and to survive the extinction of their original host. To uncover these cryptic histories, understanding the biogeography of …

Gaining Mussel: Evaluating Reintroduction Success Of Native Freshwater Mussels In Nebraska And Eastern Wyoming, Travis A. Moore

School of Natural Resources: Dissertations, Theses, and Student Research

Freshwater mussels are one of the most imperiled groups of organisms in North America, with over two-thirds of species considered threatened, endangered, or of special concern. These long-lived bivalves are essential to stream ecosystems, acting as filter feeders that improve water quality and as indicators of aquatic health. In Nebraska and Wyoming, native mussel populations have declined sharply due to habitat modification, pollution, and reduced connectivity. Two species of particular concern are the Plain Pocketbook Lampsilis cardium, listed as Tier I at-risk in Nebraska, and the Fatmucket Lampsilis siliquoidea, a Tier II at-risk species. In response, state agencies …