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Articles 121 - 150 of 36147

Full-Text Articles in Animal Sciences

The Ecotoxicological Impact Of Polystyrene On Lissachatina Fulica: A Study Of Growth,  Pedal Mucus Histological Changes, And Protein Mucus Analysis, Atin Supiyani, Wasmen Manalu, Lina Noviyanti Sutardi, Mawar Subangkit, Andriyanto Andriyanto May 2026

The Ecotoxicological Impact Of Polystyrene On Lissachatina Fulica: A Study Of Growth,  Pedal Mucus Histological Changes, And Protein Mucus Analysis, Atin Supiyani, Wasmen Manalu, Lina Noviyanti Sutardi, Mawar Subangkit, Andriyanto Andriyanto

Turkish Journal of Zoology

Lissachatina fulica mucin can be used as a nutraceutical agent depending on the  quality of their feed. Polystyrene (PS) waste harms soil and plants consumed by  snails, potentially affecting the quality of mucin production. This study investigated  the impact of PS on growth and mucus-producing cell characteristics as well as the  network pharmacology of mucin protein components. Fifty 5–6 cm L. fulica snails  (20–24 g) were fed organic waste (OW) and organic waste with PS (OWPS). After 28  days of ad libitum access to food, the snails’ mucus, meat, and shells were  collected and weighed. Tissue samples from the anterior …


Effects Of Melatonin Supplementation On Exercise Induced Stress In Horses, Hannah Clark Valigura May 2026

Effects Of Melatonin Supplementation On Exercise Induced Stress In Horses, Hannah Clark Valigura

Theses and Dissertations

Exercise is a necessary component of athletic conditioning but imposes substantial physiological stress on horses, resulting in oxidative stress, inflammation, muscle damage, and thermal strain that can impair performance and recovery. Melatonin, a neurohormone with potent antioxidant and thermoregulatory properties, has been proposed as a novel nutritional strategy to mitigate these effects. This dissertation aimed to (1) characterize serum melatonin concentrations following oral supplementation, (2) evaluate the effects of melatonin on oxidative stress, inflammation, and muscle damage biomarkers after exercise, and (3) examine its influence on physiological parameters during exercise under warm weather conditions. Across a series of controlled experiments …


The Extraction And Chemical Characterization Of The Avian Pigments Turacin And Turacoverdin, Sarah R. Bekkali May 2026

The Extraction And Chemical Characterization Of The Avian Pigments Turacin And Turacoverdin, Sarah R. Bekkali

Honors Scholar Theses

Bird coloration is a trait that extends beyond mere aesthetics as it has an extensive range of biological significance. Plumage patterns and hues can influence camouflage, mate choice, social dominance, and physiological performance. Bird fitness, their ability to survive and reproduce, is greatly dependent on color. Melanins, carotenoids, and pterins are well-studied pigment systems that are commonly found across many avian species’. Alternatively, porphyrin-based pigments are rare and less-studied as they only found in turacos a sub-Saharan African bird belonging to the family Musophagidae. This thesis focuses on two pigments of interest: turacin, the deep crimson-red pigment found in …


A Reassessment Of “Tityus” Tenuimanus Banks, 1910, As A Misidentified Leiurus Sp. (Scorpiones: Buthidae), Mohamed Mousaid, Ersen A. Yağmur, Zoe Flores, Alana Rivera, Aziza Lansari, Abdellah Bouazza May 2026

A Reassessment Of “Tityus” Tenuimanus Banks, 1910, As A Misidentified Leiurus Sp. (Scorpiones: Buthidae), Mohamed Mousaid, Ersen A. Yağmur, Zoe Flores, Alana Rivera, Aziza Lansari, Abdellah Bouazza

Euscorpius

This study re-examines the holotype of “Tityus” tenuimanus Banks, 1910, previously synonymized with Buthus atlantis Pocock, 1889 by Lourenço & Francke (1984). Our results indicate that the specimen is a misidentified representative of Leiurus Ehrenberg, 1828, as it exhibits the diagnostic characters of this genus: the central lateral and posterior median carinae of the carapace fused into a lyre-shaped configuration, and tergites I–II bearing five granular carinae (a character absent in the genus Buthus Leach, 1815). Moreover, the holotype lacks one of the most distinctive characters of the genus Tityus Koch, 1836, namely the presence of a subaculear tubercle. The …


Determining Cave Presence And Diet Variation Of The Ozark Big-Eared Bat (Corynorhinus Townsendii Ingens) From Guano Dna, Lark E. Sybrant May 2026

Determining Cave Presence And Diet Variation Of The Ozark Big-Eared Bat (Corynorhinus Townsendii Ingens) From Guano Dna, Lark E. Sybrant

ATU Theses and Dissertations 2021 - Present

The Ozark big-eared bat (Corynorhinus townsendii ingens; OBEB) is federally endangered in Arkansas, where it persists in a few small, geographically restricted populations within the Ozark National Forest. Although the region contains many caves that appear suitable for OBEB, expanded survey efforts are needed to locate additional roost sites for monitoring and protection. Effective conservation also requires a clear understanding of their distribution and diet. Traditional cave surveys can be disruptive and often miss cryptic species, and earlier diet studies based on manually sorting prey remains provided only coarse taxonomic resolution and overlooked soft‑bodied insects. To address these …


Scorpions In Brazilian Caves And Other Subterranean Habitats, Jonas E. Gallão, Bruno D, Lenhare, Misael Oliveira-Neto, Maria E. Bichuette May 2026

Scorpions In Brazilian Caves And Other Subterranean Habitats, Jonas E. Gallão, Bruno D, Lenhare, Misael Oliveira-Neto, Maria E. Bichuette

Euscorpius

Arachnids have successfully colonized subterranean environments. Compared to spiders, harvestmen, and pseudoscorpions, scorpions have a moderate number of subterranean species, including troglophiles and troglobites. Among the four families and 184 species and three subspecies of scorpions found in Brazil, three families and at least 33 species and one subspecies have been documented in subterranean habitats. This study presents a faunistic list of scorpion occurrences in caves and other types of subterranean habitats in Brazil, along with distribution maps and an attempt to classify species based on their use of and dependence on subterranean environments.


Bio 340 Final Project: Effects Of Light Pollution On Bat Activity, Cael Schneider May 2026

Bio 340 Final Project: Effects Of Light Pollution On Bat Activity, Cael Schneider

Biology Student Scholarship

Cael Schneider - Environmental Biology ‘28

Artificial light at night (light pollution) is an increasing consequence of urbanization and can disrupt nocturnal wildlife. Bats are especially susceptible, as they rely on dark skies for navigation, predator avoidance, and foraging. The effects of artificial light may vary among species due to differences in foraging strategies, habitat use, and light tolerance.  Previous research has documented negative effects of artificial light on bat foraging, roosting, breeding, and hibernation. However, some species, such as red bats, may forage near artificial lights where insects are abundant. Species including the big brown bat, hoary bat, and …


The Genus Nebo Simon, 1878 (Scorpiones: Diplocentridae) In Oman, Graeme Lowe May 2026

The Genus Nebo Simon, 1878 (Scorpiones: Diplocentridae) In Oman, Graeme Lowe

Euscorpius

No abstract provided.


Membrane Progestin Receptors Α And Β (Paqr7 And 8) Are Necessary For Oogenesis In Zebrafish, Md. Almamun Farid, Md. Razain Tanvir, Takumi Mouri, Eisei Tsutsumi, Md. Sohanur Rahman Sohan, Md. Ekramul Hasan, Md Saydur Rahman, Chihiro Yamamoto, Akiteru Maeno, Toshinobu Tokumoto May 2026

Membrane Progestin Receptors Α And Β (Paqr7 And 8) Are Necessary For Oogenesis In Zebrafish, Md. Almamun Farid, Md. Razain Tanvir, Takumi Mouri, Eisei Tsutsumi, Md. Sohanur Rahman Sohan, Md. Ekramul Hasan, Md Saydur Rahman, Chihiro Yamamoto, Akiteru Maeno, Toshinobu Tokumoto

School of Integrative Biological & Chemical Sciences Faculty Publications

Paqr7 and paqr8 are genes encoding membrane progestin receptor αand β (mPRα and mPRβ, respectively), which are currently classified as members of the progestin and adipoQ receptor (PAQR) family. For mPRα, the first identified mPR gene, there are two paralogs in zebrafish, paqr7a and paqr7b. In order to elucidate the physiological functions of the mPR subtypes, we created gene knockout (KO) fish by editing seven paqr genes in zebrafish and analyzing their phenotypes. The null-mutant strains of paqr7a, paqr7b, and paqr8 presented no significant abnormalities in reproductive functions. Thus, we generated a triple-gene knockout (TKO) strain of …


Effect Of Accelerated Adaptation Programs On Feedlot Performance And Health Of Steers Drenched With Megasphaera Elsdenii And Quantifying And Partitioning Multi-Year Carbon Dioxide And Methane Fluxes In A Grazed Temperate Pasture, Rebecca Mcdermott May 2026

Effect Of Accelerated Adaptation Programs On Feedlot Performance And Health Of Steers Drenched With Megasphaera Elsdenii And Quantifying And Partitioning Multi-Year Carbon Dioxide And Methane Fluxes In A Grazed Temperate Pasture, Rebecca Mcdermott

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

With strong consumer demand for beef and increasing concern about the environmental impacts of beef production, improving production efficiency and advancing the understanding of the environmental footprint are critical for the long-term sustainability of beef production systems. The first experiment evaluated the effect of accelerated adaptation strategies, using energy intake and cattle behavior, on feedlot performance, carcass characteristics, and health of yearling steers drenched with exogenous Megasphaera elsdenii. Accelerated adaptation programs (0, 7, or 14 d transition to 100% finisher) were compared to a traditional 21-d adaptation. Dry matter intake responded quadratically across treatments, with the greatest intake observed in …


Nitrogen-Use Efficiency Of Irrigated Rhodes Grass In Northern Wa, Carla Milazzo, Christopher Ham, Geoff Moore May 2026

Nitrogen-Use Efficiency Of Irrigated Rhodes Grass In Northern Wa, Carla Milazzo, Christopher Ham, Geoff Moore

Grain and other field crops research reports

Cultivation of irrigated fodder and forage crops to intensify northern beef production in the west Kimberley and Pilbara has seen significant private investment over the past decade. To support this growing investment, the Department of Primary Industries and Regional Development (DPIRD) carried out replicated, randomised trials on irrigated Rhodes grass near Broome.

High nitrogen (N) inputs are required for subtropical grasses to achieve annual growth rates of up to 40 t DM/ha and there is growing scrutiny of these systems to prevent nutrient losses to groundwater and downstream ecosystems. The research aimed to establish N (urea) response curves to five …


Investigating The Effects Of Stress On The Passive Transfer Of Antibodies From Colostrum To The Newborn Calf, Audrey F. Dykes May 2026

Investigating The Effects Of Stress On The Passive Transfer Of Antibodies From Colostrum To The Newborn Calf, Audrey F. Dykes

Animal Science Undergraduate Honors Theses

The objective of the current study was to examine passive transfer of immunoglobulins A (IgA) and G (IgG) to the calf in relation to dam’s fecal cortisol and lactoferrin. In July 2024, late-gestation, Angus crossbred heifers pregnant by artificial insemination (n = 30) were moved to the University of Arkansas Division of Agriculture Stocker Unit and housed in 0.42-ha grass paddocks for each heifer. Calving began in mid-August. Heifers were observed routinely throughout the workday and then at 8 p.m., 12 a.m., and 6 a.m. After calving, the calf was allowed to stand and suckle once then dam sample collection …


Differences In Local And Systemic Immune Responses To Primary And Secondary Immunizations With The Herpesvirus Of Turkeys (Hvt) Vaccine In Layer Pullets., Allie K. Bowerman May 2026

Differences In Local And Systemic Immune Responses To Primary And Secondary Immunizations With The Herpesvirus Of Turkeys (Hvt) Vaccine In Layer Pullets., Allie K. Bowerman

Poultry Science Undergraduate Honors Theses

Marek's disease, caused by a herpesvirus, is a major issue in poultry production due to its high mortality rate. The herpesvirus of turkeys (HVT) vaccine has been used as a crucial measure to mitigate outbreaks of Marek's disease in poultry production; however, little is known about the immune response to the HVT vaccine. In this study, we examined how primary and secondary intradermal (i.d.) vaccination with the HVT vaccine in the growing feather (GF) pulp affects local and systemic immune responses, including cellular, antibody, and cytokine responses. Six 9-week-old and six 19-week-old Light-brown Leghorn (LBL) pullets received a primary or …


Assessing The Impact Of Toxic Fescue Consumption During Gestation On Muscle Growth Gene Expression And Beef Color Quality Of The Offspring, Madison Blank May 2026

Assessing The Impact Of Toxic Fescue Consumption During Gestation On Muscle Growth Gene Expression And Beef Color Quality Of The Offspring, Madison Blank

Animal Science Undergraduate Honors Theses

Endophyte-infected tall, toxic fescue is the most common forage for beef cattle in the southeastern U.S. However, exposure to this forage causes detrimental effects on the health of gestating cattle. The exposure to toxic fescue during gestation has been shown to impact fetal development during pregnancy and their offspring’s subsequent growth. However, limited information is currently available on the impact of this exposure on the meat quality of the offspring. Our objective is to determine how the dam’s exposure to toxic fescue during gestation impacts the beef color and quality of the final offspring.

A total of 22 animals (11 …


The Evaluation Of Broiler Lines Divergently Selected For Water Conversion Ratio Under Acute And Chronic Stress, Baileigh B. Cash May 2026

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 May 2026

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 May 2026

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 May 2026

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 May 2026

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 May 2026

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 May 2026

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 CTmax, or Critical Thermal Maximum, and Clark-type polarographic oxygen microelectrodes, the physiological metabolic effects are investigated. CTmax is examined in Common Shiners, Luxilis cornutus, and is shown to be modulated by parasitism: uninfected fish had the highest CTmax average of 37.0°C, whereas heavily infected fish had decreased CTmax 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 May 2026

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 May 2026

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 …


Effects Of Mineral Supplementation On Ovine Performance, Forage Selectivity, And Rangeland Utilization In Southern Utah, Ryan A. Spurling May 2026

Effects Of Mineral Supplementation On Ovine Performance, Forage Selectivity, And Rangeland Utilization In Southern Utah, Ryan A. Spurling

All Graduate Theses and Dissertations, Fall 2023 to Present

Sheep producers in the Intermountain West region of the US rely on productive rangeland ecosystems that vary widely in forage composition and nutrient availability. As such, supplementation is often necessary to offset dietary deficiencies. Soils and forages grown on rangelands are known to be highly variable in mineral content. Even so, a third to half of the producers in the Intermountain West choose not to provide a complete mineral supplement. Rangeland environments are often characterized by rugged geographical features that make optimal supplement placement difficult. New advances in technology have allowed us to measure individual animal intake on rangelands via …


Preserving The Past: Exploring The Last Frontier's Ecosystem Shifts And Biodiversity Of The Tallgrass Prairies, Gisell Maldonado, Amelia Villaseñor May 2026

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 …


The Effect Of Including A Yeast Culture Containing Essential Oils In Receiving Cattle Diets On Growth Performance And Health, Taylor Deanna Foster May 2026

The Effect Of Including A Yeast Culture Containing Essential Oils In Receiving Cattle Diets On Growth Performance And Health, Taylor Deanna Foster

Animal Science Undergraduate Honors Theses

Due to the increased risk of bacterial populations developing resistance to current antibiotics, consumer perceptions surrounding the utilization of antibiotics use in cattle, and the endemic incidence of bovine respiratory disease (BRD) among growing and finishing cattle, alternative management strategies to improve the health of cattle must be developed. The objective of this study was to evaluate the use of a supplement containing a yeast culture and an essential oils blend (YEO) on the health and growth performance of stocker calves at high-risk for BRD. Crossbred male beef calves (n = 185) received on two separate dates were used in …


Influence Of Increased Supplementation Of Organic-Complexed Zinc To Beef Cows During Gestation: Effects On Preweaning Health Of Offspring, Naija N. Sharpley May 2026

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 May 2026

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 May 2026

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 May 2026

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 …