Digital Commons Network^™

Establishing Methods For In Vitro Static Culture Of Gut Microbiomes For Nutritional Intervention Studies, Jeremy Mathew Case

Undergraduate Honors Capstone Projects

Lipid oxidation products (LOPs), which form during high-heat processing of oils common in Western diets, are known to cause inflammation and cellular damage. While LOPs have been implicated in exacerbating colitis and promoting colon tumorigenesis in mouse models, their direct impact on the gut microbiome remains poorly understood. This capstone project aimed to develop a low-cost in vitro protocol to culture the mouse gut microbiome under anaerobic conditions, enabling future investigations into the direct effects of bioactive dietary compounds such as LOPs. The study also assessed whether viable microbial communities could be recovered from fecal samples stored at -80°C. Fecal …

Phylogeny And Historical Biogeography Of Uroleucon Aphids, Audrey Michelle Mullen

Undergraduate Honors Capstone Projects

The aphid genus Uroleucon (Aphididae: Aphidinae: Macrosiphini) is a diverse group of about 230 species found globally in most temperate regions, principally in the northern hemisphere. Only 23 species are described from the southern hemisphere, in South American temperate regions such as Chile, Argentina, and Peru. However, the origins of the South American species are unknown, as are the relationships of these taxa to northern hemisphere Uroleucon species. This study seeks to establish the relationships between Uroleucon aphids native to South America and their North American and Eurasian counterparts using genetic data. We use phylogenetic analysis of cytochrome c oxidase …

Adaptation Of Influenza A Virus Strains A/Anhui/1/2013 (H7n9) And A/Shanghai/1/2013 (H7n9) For Development Of Effective Mouse Models, Spencer T. Mullen

Undergraduate Honors Capstone Projects

The emergence of avian Influenza A (H7N9) virus strains in humans poses a significant threat to human health globally due to their pandemic potential, limited human immunity, and lack of virus-specific interventions. This capstone aims to address some of the limitations in antiviral research regarding Influenza A H7N9 virus by adapting two low-pathogenic virus strains A/Anhui/1/2013 (H7N9) and A/Shanghai/1/2013 (H7N9) to BALB/c mice through sequential passaging through lung tissue. Following 12 serial passages, increased virulence was observed as evidenced by increased virus replication, increased weight loss, and increased mortality in infected mice. Titration of the initial non-adapted virus isolates were …

Creating A Stat2 Knock-Out Rat With Crispr/Cas9 Using I-Gonad, Isabella Dejesus

Undergraduate Honors Capstone Projects

Through the use of genetically modified animals, a more holistic understanding of physiologic responses to various diseases and pathologies can be obtained^7,19. The STAT2 gene encodes a protein called Signal Transducer and Activator of Transcription 2 and is an excellent target for genetic manipulation due to its essential role in type I and III interferon signaling pathways¹¹. A member of the STAT family of transcription factors, this protein is directly involved in mediating cellular responses to various cytokines and growth factors, particularly those related to the innate immune response¹¹. While the STAT2 signaling pathway …

Investigation Of Immune/Performance Trade-Offs In Neonate Children's Pythons (Antaresia Childreni), Ellie Hartman

Undergraduate Honors Capstone Projects

Energetic costs and constraints are key considerations when analyzing an organism’s life history and may require trade-offs to be made between different life history traits. One of these trade-offs occurs between investment in immunity and performance. The purpose of this study is to discover if this trade-off influences behavior in neonate Children’s pythons (Antaresia childreni). We hypothesize that snakes undergoing an immune response will have reduced behaviors promoting survival. To test this hypothesis, neonate Children’s pythons were randomly assigned to receive an immune challenge of keyhole limpet hemocyanin (KLH) or a vehicle injection as a control. Two days …

Sibship Analysis Of Fall And Spring Spawn Gulf Sturgeon Eggs In The Choctawhatchee River, Florida, Lyric Mccullouch

Honors Theses

The Gulf sturgeon (Acipenser oxyrinchus desotoi) is an anadromous species that inhabits rivers along the northern Gulf of Mexico. Facing challenges from overfishing and habitat alteration, the Gulf sturgeon is listed as threatened under the Endangered Species Act. This study investigated the genetic distinctiveness of fall and spring spawning groups of Gulf sturgeon in the Choctawhatchee River, a critical habitat for the species. In this study, I used microsatellite loci to analyze Gulf sturgeon eggs previously collected in the fall and spring of 2019 and 2020. The goals of this study were to verify the genetic identity of …

Navigating The Challenges Of Coccidioides Surveillance: Insights From The Environment Of El Paso County, Texas, Tanzir Hossain

Open Access Theses & Dissertations

Coccidioidomycosis, or Valley fever, is a fungal infection resulting from the inhalation of spores from the Coccidioides species (C. immitis and C. posadasii), native to arid areas of the Western Hemisphere. Coccidioidomycosis presents considerable health hazards and can be fatal. It affects between 206,000 and 360,000 individuals annually, leading to 700 to 1,100 fatalities in the United States alone. In response to these issues, extensive research has concentrated on therapeutic goals for this infectious disease. Nonetheless, more limited research has focused on the environmental detection of its causative fungi, which is crucial for forecasting treatment needs and formulating preventive strategies. …

Investigating Self-Healing Mechanisms In Host-Pathogen Interactions: A Literature Review Of Macrophage Functions In Tuberculosis, Blessing Savusa

Open Access Theses & Dissertations

Tuberculosis (TB) remains a leading cause of mortality, particularly in underdeveloped regions. Mycobacterium tuberculosis (Mtb) is regarded as one of the most successful pathogens due to its ability to evade host immunity and persist within granulomas. Macrophages are the first-line host defenders that engulf Mtb into phagosomes, which initiates lysosomal activity for degradation. However, the virulence factor of Mtb is able to inhibit phagolysosome fusion. The host immune system forms granulomas to contain the mycobacterium at the site of inflammation. This, in turn, causes a necrotic state and causes tissue damage from the prolonged inflammation. Studies suggest that the host's …

"Until There Is Nothing Left:" The Environmental And Social Impact Of Extractivist Industries In Grant County, New Mexico 1852-1999, Benjamin Shultz

Open Access Theses & Dissertations

This dissertation research expands and deepens our understanding of the environmental and social impact of the extractivist industries in Grant County, New Mexico, from 1852 to 1999. Much of the scholarship around mining in the historiography tends to focus on Arizona and Northern New Mexico, given the centralization of the mining industry in places like Taos and Santa Fe. The impact of the mining industry on the unique ecosystem and people who resided in Grant County, New Mexico, has not been as thoroughly researched by scholars. Thus, this dissertation extends the literature by revealing how the extractivist industries permanently changed …

Intratumoral Fibrin As A Novel Immunomodulatory Factor In Pancreatic Ductal Adenocarcinoma, Mazharul Karim

Open Access Theses & Dissertations

In-situ coagulation is a common clinical feature of pancreatic ductal adenocarcinoma (PDAC) that presents a highly thrombotic and crosslinked insoluble fibrin (x-fibrin)-laden tumor stroma (FibTS). However, the specific impact of FibTS on immune cells behavior remains largely unexplored in this poorly infiltrated tumor. We aimed to elucidate how FibTS in PDAC regulates immune cell infiltration, polarization, and crosstalk that favors immunosuppressive microenvironment and tumor growth. We characterized human PDAC tissues by multiplex immunostaining and checked the spatial distribution of immune cells based on the presence of x-fibrin. We investigated how FibTS influences the infiltration of tumor-associated macrophage (TAM) and T-cell …

Development Of A Behavioral Paradigm To Monitor Seizure Susceptibility And Severity In A Zebrafish Model Of Cblx Syndrome, Claudia Berenice Gil

Open Access Theses & Dissertations

Methylmalonic acidemia and homocysteinemia cblX type (cblX) (MIM#309541) is a rare, X-linked recessive disorder caused by a mutation in the HCFC1 gene. This disorder is characterized by multiple congenital anomalies which include intellectual disability, brain malformations, intractable epilepsy, microcephaly, and facial dysmorphia. The most severe symptom of cblX is intractable epilepsy which is 100% penetrant. Our lab developed a zebrafish model with a mutation in the zebrafish hcfc1a ortholog to study the mechanisms underlying seizure phenotypes in cblX. Our laboratory previously showed that mutation of hcfc1a results in increased number and proliferation of neural precursor cells (NPCs) and an increase …

The Bullied Prairie Vole: Modeling Depression And Anxiety Through Social Defeat Stress, Minerva Rodriguez

Open Access Theses & Dissertations

Stress-induced illnesses, such as major depression and anxiety, are significant global causes of disability. This highlights the need for reliable animal models that accurately mimic social stress-induced maladaptations, thus, allowing the experimental study of the etiology of such disorders. Prairie voles (Microtus ochrogaster), known for their human-like bi-parental behavior and monogamous partner preferences, are a relevant model for the study of stress-induced psychopathologies. For this reason, in this dissertation, I examined whether exposing voles to the social defeat stress (SDS) paradigm, an experimental approach that captures bullying behavior, would result in both depression and anxiety-related profiles. To do this, experimental …

Regulation Of Ccr7 Signaling Events By G-Protein-Coupled Receptor Kinases 2 And 3, Anahi Sanchez

Open Access Theses & Dissertations

G protein-coupled receptors (GPCR) can bind multiple ligands, leading to differential signaling events termed biased signaling. C-C chemokine receptor 7 (CCR7) is a GPCR known to have biased signaling between the two ligands it binds to, CCL19 and CCL21. Binding of C-C Chemokine Ligand 19 (CCL19) promotes a high level of CCR7 phosphorylation, while CCL21 leads to a much lower level of CCR7 phosphorylation; findings observed in HEK and dendritic cells. GPCR kinases (GRKs), which can control the phosphorylation patterns of a GPCR, are hypothesized to regulate biased signaling of a receptor. GRK expression differs between cell lines and cell …

Ghrelin And Decision-Making: Exploring Its Role In Food Reward, Novelty-Seeking, And Cost Valuation, Serina A. Batson

Open Access Theses & Dissertations

When low energy levels are detected, Ghrelin, a peptide hormone, is produced in the fundus of the stomach. Referred to as the "hunger hormone", Ghrelin is traditionally associated with increased food intake and blood sugar levels. A key modulator in the gut-brain interaction, Ghrelin's growth hormone secretagogue receptor can be found widely across the cortico-striosomal circuit. Critical for decision-making, Ghrelin-based manipulation of this circuit can directly affect reward and cost valuation. While Ghrelin is uniformly considered to increase the valuation of food-based rewards, little research has explored its impact on non-food-based rewards or its effects on cost valuation. Therefore, to …

Initial Impacts Of Different Fertilizers On Improved East Texas Equine Pastures, Carolina De Leon, Brian Oswald, Leland Thompson, Candis Scallan

Electronic Theses and Dissertations

ABSTRACT

In Texas, approximately 1.6 million acres support an equine population exceeding 748,000 horses. This study assessed the effects of organic and inorganic fertilizer treatments on improved Bermudagrass (BG) and other vegetation (OTH) in overgrazed equine pastures at the Stephen F. Austin State University Equine Center. Treatments included equine manure (H), broiler poultry litter (P), and a commercial 13-13-13 fertilizer (C), with application rates based on pasture requirements.

Initial vegetation cover was evaluated using the Daubenmire cover class method in September 2024, followed by a 60-day undisturbed growing period. Final biomass (g/2ft² converted to lbs/ac) and percent cover measurements were …

Polyphenol-Protein Interactions In Pigmented Cereals – A Clean-Label Approach To Tailor Starch Viscosity, Annegret Jannasch

Graduate Theses and Dissertations

Viscosity plays an important role in the food industry as it affects the quality, processing stability, and shelf-life of food and impacts physiological responses such as satiation and satiety. Greater viscosity reduces food intake by increasing the perception of satiety, primarily by delaying gastric emptying and increasing tactile stimulation. Starch is commonly added to food products as a viscosifying ingredient, which often involves chemically modifying the starch via cross-linking, to enhance its resistance to high shear, temperature and acidity. However, chemically modified starches are not “clean-label” ingredients due to the use of toxic chemicals. Therefore, further exploration is needed to …

Identifying Microbial Complexities And Control Strategies At Pre-Harvest Poultry Production, Tolulope Tiwa Ogundipe

Graduate Theses and Dissertations

While significant progress has been made in post-harvest control of Salmonella in the poultry industry, the development of effective pre-harvest intervention strategies remains critical for reducing foodborne pathogens. Environmental reservoirs such as poultry litter and drinking water systems (DWS) are potential harborage sites for Salmonella and other microbial communities. Understanding the microbiota of these environments, including biofilms within water lines, is essential to identifying factors contributing to Salmonella colonization and improving pre-harvest control approaches. This study aimed to evaluate the incidence and quantity of Salmonella in poultry litter and water lines, characterize the microbial populations in these environments, and assess …

Evaluation Of Fluridone In Rice, Maria Carolina De Carvalho Rocha Souza

Graduate Theses and Dissertations

The increasing pressure of Palmer amaranth [Amaranthus palmeri (S.) Watson] in rice (Oryza sativa L.) fields demands new chemical control options to manage this weed. The recent labeling of fluridone on this crop from the three-leaf rice stage offers an additional residual herbicide for battling Palmer amaranth; however, research is needed to evaluate its effectiveness and rice tolerance. Field experiments were conducted to evaluate Palmer amaranth control and rice tolerance to fluridone across different locations in Arkansas in 2022, 2023, and 2024. Preemergence (PRE) applications of fluridone at 168 g ai ha^⁻1; (1× label rate) and 336 …

Crispr-Cas9 Integration Of Salmon Elovl2 In Zebrafish Enhances Lc-Pufa Biosynthesis And Growth Across Diets, Waleed Sami J. Al-Bachry

Graduate Theses and Dissertations

Fish are a rich source of EPA and DHA, which are well-known long-chain polyunsaturated fatty acids (LC-PUFAs). The sustainable production of these essential fatty acids poses significant challenges, mainly due to our dependence on marine fish and certain nuts. CRISPR-Cas system was utilized to insert the elongation of long-chain fatty acids-like2 (Elovl2) gene from Salmo salar into Danio rerio. Elovl2 was introduced at 10-15-minute post-fertilization, and successful integration confirmed by PCR genotyping, sequencing and expression of EGFP. Approximately 67% of injected embryos successfully exhibited EGFP and sequence results verified the gene integration of Salmo salar Elovl2 at the first start …

Variation In Stress Response Regulation Across Natural Isolates Of Saccharomyces Cerevisiae, Crystal Christine Crook

Graduate Theses and Dissertations

The stress response of Saccharomyces cerevisiae is a valuable area of study for understanding cellular adaptation mechanisms that govern survival in fluctuating environments. This dissertation investigates stress response regulation in yeast through the roles of Hog1 mitogen-activated protein kinase (MAPK) and the post-transcriptional regulator Mkt1, a key post-transcriptional regulator, in diverse wild yeast isolates. Hog1 is traditionally known for its central role in osmotic stress regulation in the high-osmolarity glycerol (HOG) pathway. This study expands the functional scope of Hog1 to include oxidative and ethanol-induced stress responses.

In parallel, we investigate post-transcriptional regulation of stress responses by the Mkt1 interactome, …

Fixed-Time Artificial Insemination Protocols Using Pre-Synchronization In Suckled Beef Cows, Wyatt Eugene Weber

Graduate Theses and Dissertations

Adoption of artificial insemination by beef producers has been limited within the United States. Estrous synchronization (ES) for fixed-time artificial insemination (FTAI) has been one of the most effective ways to implement artificial insemination into beef production systems, but its efficiency has primarily been restrained by the dependency on the effectiveness of the initial gonadotropin releasing hormone (GnRH) injection in many FTAI protocols. The hypotheses of these studies were to determine practical methods of pre-synchronization to improve current FTAI protocols, ultimately increasing beef herd reproductive performance. The objective was to evaluate the use of prostaglandin F2α (PGF) and progesterone (P4) …

Evolutionarily Conserved Functions Of The Gene Frazzled In Midline Axon Guidance In Drosophila Melanogaster And Tribolium Castaneum., Piyasi Ghosh

Graduate Theses and Dissertations

Axon guidance in bilaterians is often controlled by various signaling pathways in the nervous system, which determine the fate of the axons if they cross the midline or not. One such pathway involved is the ligand-receptor pair Netrin (Net) and Frazzled (Fra), which is also known as the attractive pathway that promotes midline crossing axons in insects and other bilaterians. Orthologs of the pathway ligand Netrins and their receptors Frazzled [Fra] in insects and Deleted in Colorectal cancer [DCC] in vertebrates are widely conserved in bilaterians. How well these regulatory roles of the protein are conserved is poorly understood. In …

The Efficacy Of Foam-Based Hand Sanitizers For The Control Of Enveloped And Non-Enveloped Virus Transmission, Francis Torko

Graduate Theses and Dissertations

Infectious disease transmission due to viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus, human noroviruses (HuNoV), and hepatitis A, can occur via person-to-person contact or contaminated surfaces. Effective hand hygiene, including hand washing and use of hand sanitizers, is considered a critical tool for the control of infectious disease transmission, as recommended by the United States Centers for Disease Control and Prevention and the World Health Organization. However, while research on hand washing efficacy is well-documented, research on hand sanitizer efficacy, particularly for foam-based products, remains limited. This research addressed critical gaps in the area of …

Bacterial Chondronecrosis With Osteomyelitis In Broiler Chickens: Experimental Lameness And Additive Probiotic Treatments, Amanda Anthney

Graduate Theses and Dissertations

With the global population already surpassing 8.2 billion and expected to reach 9.7 billion by 2050, the poultry industry has seen a surge in demand due to its unmatched efficiency and affordability for consumers across the globe. Selective breeding and quality nutrition developments since the industry's commercialization have allowed producers to grow broilers up to 7 pounds by market age. While this extraordinarily efficient process has allowed quality poultry products to be available worldwide, the modern-day broiler has developed a multitude of musculoskeletal issues. Due to the lack of integral skeletal development to match the rapid production of muscle tissue, …

Characterization Of Streptococcus Gallolyticus: An Emerging Pathogen Causing Turkey Streptococcosis, Latasha S. Gray

Graduate Theses and Dissertations

During the past five years, there has been an increased occurrence of Streptococcus gallolyticus in young turkey poults. This emerging pathogen previously affected turkey flocks without any indication of disease prior to acute mortality. However, recently there has been two cases of neurological presentation associated with S. gallolyticus subsp. pasteurianus that are unique to traditional disease presentation in turkey poults. The objectives of the present dissertation were to compile data associated with the two neurological cases and compare different S. gallolyticus strains as well as pathogenic Enterococcus cecorum to the neurological strains. The two neurological cases occurred between July and …

Fish Cultivation In Fallow Season Rice Fields: Effects On Landscape Methane Emissions, Samuel Carroll

Graduate Theses and Dissertations

Co-cultivation of aquatic animals and rice in the same field is a fairly common practice in various parts of the world, with a number of well-established agro-ecological benefits, such as decreasing the need for chemical pesticides and fertilizers, increasing soil organic matter, and reducing the land area needed for agricultural production. One area of environmental concern in rice production is greenhouse gas emissions. Rice production contributes about 10% of global anthropogenic methane (CH₄) emissions. Currently around 27.5% of Arkansas rice fields are flooded in the winter, which can increase CH₄ emissions in the fallow season by 45% …

Stereotypic Behaviors And Physiological Indicators Of Stress Occur In Horses With Restricted Durations Of Turnout, Elizabeth E. Rodgers

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

The confinement of horses to stalls with limited or no turnout time restricts their natural roaming behaviors, which potentially increases stress and behavioral stereotypies. This study investigated the impact of turnout duration on behavioral and physiological stress indicators in healthy horses. Adult horses (n = 11) were enrolled in a 3 treatment (0-, 15-, and 60-minute turnout/day) Latin square design, including 3 12 d experimental periods over 6 weeks. Horses were acclimated to turnout (24.38 x 64.01m indoor arena) and stalls (2.74 x 4.87m - 3.66 x 3.66m) stalls prior to data collection on day 1. Experienced handlers managed …

Digestibility, Palatability, And Nutrient Composition Of Three Species Of Whole Prey In Three Species Of Snakes, Morgan R. Kienzle

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

Snakes in human care often lack diversity in the diet. Rodents account for the majority of meals, while wild snakes are consuming a varied diet composed of multiple different whole prey species. By feeding only one species of prey, the chance of nutrient deficiencies and other health concerns increases. To promote variety in the managed diet, two commercially available whole prey species (mice (Mus musculus) and chicks (Gallus spp.)) and one novel species (Seba’s short-tailed bats (Carollia perspicillata)), were analyzed for their dry matter (DM), organic matter (OM), crude protein (CP), crude fat …

Evaluation Of Two Different Sweet Bran Products On Beef Cattle Digestion Characteristics And A Review Of Ramp As An Alternative Step-Up Program, Emily K. Hoefling

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

Two Sweet Bran products were evaluated at 13%, 18%, and 23% inclusion of the diet on total tract digestibility and rumen fermentation parameters. Seven ruminally cannulated, heifers were used in a 6 x 7 row-column design with 21-d periods consisting of 16-d adaptation period followed by a 5-d collection. Dietary treatments were designed in a 2 x 3 factorial arrangement with 6 periods. Factors included two Sweet Bran products that differed in particle size (Sweet Bran-SP; GMD = 1.79 mm or Sweet Bran-LP; GMD = 2.51 mm) and three dietary inclusion (13%, 18%, or 23% of diet dry matter). The …

Methane Mitigation And Its Effects On Energy Utilization In Lactating Dairy Cattle, Shan C. Sherwood

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

Improved methane (CH₄) mitigation strategies are needed to achieve the greenhouse gas emission goals of the dairy industry. The first experiment was conducted to evaluate the effects of feeding black cumin (Nigella sativa) seed oil and acetate (BCA) on CH₄ production and whole-animal energy utilization. Twelve dry Jersey cows were used in a 2-period crossover design study with 28d periods. The BCA treatment was compared to a control diet with corn oil. Both BCA and corn oil were added to the base diet as a top dress. Results from this study did not show any …