Medicine and Health Sciences Commons^™

Impact Of Dietary Modification On Aflatoxicosis In Poultry, Xi Chen

Open Access Dissertations

Aflatoxin contamination in feed and feed ingredients is of high worldwide prevalence, posing serious risks to the livestock industry. A series of studies were conducted to better understand the comprehensive impact of aflatoxicosis and its interrelationships with dietary modifications in broiler chicks and ducks. Results of these studies emphasize the many factors that the severity of aflatoxicosis depends on, including animal species, age, presence of mycotoxin adsorbent, and concentration of major dietary nutrients. Exposure to 2 mg/kg cultured AFB1 led to reduced feed intake, BW gain, depressed feed efficiency, increased relative liver weight, negatively affected serum measures and complement activity, …

Evaluation Of Several Pre-Clinical Tools For Identifying Characteristics Associated With Limb Bone Fracture In Thoroughbred Racehorses, Anthony Nicholas Corsten

Open Access Theses

Catastrophic skeletal fractures in racehorses are devastating not only to the animals, owners and trainers, but also to the perception of the sport in the public eye. The majority of these fatal accidents are unlikely to be due to chance, but are rather an end result failure from stress fractures. Stress fractures are overuse injuries resulting from an accumulation of bone tissue damage over time. Because stress fractures are pathological, it is possible that overt fractures can be predicted and prevented. In this study, third metacarpals (MC3) from 33 thoroughbred racehorse comprised of 8 non-fractured controls and 25 horses that …

The Impact Of Tickling Rats On Human-Animal Interactions And Rat Welfare, Megan Renee Lafollette

Open Access Theses

Rats initially fear humans which can lead to negative affect, poor welfare, and difficult handling. Also, modeling and measuring positive affect states in rats can pose an additional challenge. Heterospecific play, or “tickling,” is a handling habituation technique that mimics rat rough-and-tumble play that is being used to study positive affect. It can also be used to reduce fear of human, improve welfare, and elicit a positive affect state. However, current studies implementing the technique in laboratory rats use a wide variety of protocols to achieve differential results. Unlike in laboratory environment, pet store rats experience high levels of novelty …

Gonadal Intersex In Teleosts: Mechanisms, Molecular Biomarkers And Diagnostic Assays, Ahmed M.E. Abdel-Moneim Mohamed

Open Access Dissertations

Natural and synthetic estrogenic and androgenic compounds are continuously released into aquatic ecosystems. Exposure of teleost fishes to these contaminants can negatively impact sex differentiation and reproductive output. Specifically, development of gonadal intersex in gonochoristic (fixed sex) fish species has been studied extensively in relation to exposure to this class of compounds. The main objectives of this dissertation were to: 1) conduct field and laboratory studies to investigate the molecular signaling pathways behind the development of gonadal intersex; and 2) establish molecular biomarkers and assays for testing the ability of environmental pollutants to develop this condition using a battery of …

Evaluating The Physical Welfare Of Dogs In Commercial Breeding Facilities In The United States, Moriah J. Hurt

Open Access Theses

Despite high levels of public concern, the state of commercial breeding (CB) dog welfare is largely unknown. Therefore, this study aimed to characterize the physical welfare of dogs in CB facilities and their environment in Indiana. This study specifically aimed 1) to characterize dog foot health in CB facilities as a function of the length of time dogs were housed on a given flooring substrate, 2) to characterize visual dog body cleanliness and visual kennel cleanliness as a function of the flooring substrate, 3) to determine the efficacy of kennel cleaning procedures and 4) to characterize the dog dental and …

The Interactive Effects Of Pesticide Exposure And Infectious Disease On Amphibian Hosts, Katherine M. Pochini

Open Access Theses

Natural systems are home to a multitude of natural and anthropogenic stressors, which draw an array of effects on ecological communities. While these effects have been investigated individually, it is important, given the routine co-occurrence of these stressors, to understand their interactive effects. Pesticide exposure and infectious disease are two common, co-occurring stressors that each have documented detrimental effects on species and, as evidence suggests, may have interactive effects. Moreover, existing research suggests that these interactive effects are highly context dependent, eliciting different results based on species, disease agent, toxin, and environment. Given the variability with which species may experience …

Influence Of Dietary Component Manipulation And Feed Management Strategies On Growth And Rumen Development Of Weaned Dairy Heifers, Tana Shea Dennis

Open Access Dissertations

Well-developed replacement heifers provide a central foundation for the continued success of the dairy industry. Emphasis on improving pre-weaned calf nutrition has predominated in the industry, but opportunities exist to improve post-weaning heifer nutrition and management. We aimed to evaluate common feed management strategies seen in the industry and their effects on growth, feed efficiency (G:F), and rumen development of calves from birth to 8 mo of age using pen- and individually-fed animal trials. Little information exists regarding post-weaning performance and rumen development of calves fed conventional or high planes of nutrition pre-weaning; therefore, we evaluated two milk replacer feeding …

Evaluating The Prevalence And Effectiveness Of Breed-Specific Legislation, Felicia E. Trembath

Open Access Dissertations

Dog bites pose a persistent public health problem, which some jurisdictions pass breed-specific legislation (BSL) to address. However, very little non-anecdotal evidence regarding the efficacy of BSL has been presented. Currently, BSL research is hampered by the absence of standard terminology, an established prevalence, or a scientific consensus on its effectiveness. The purpose of this study is to propose standardized terminology for BSL, establish the prevalence of each type of BSL in the USA, and conduct a systematic review of the effectiveness of BSL.

After review of terminology currently in use, as well as review of the regulatory actions of …

Immune Modulating Functions By Soypeptide Lunasin In Cancer Immunotherapy, Chun-Yu Tung

Open Access Dissertations

Chemotherapy is currently the mainstay of treatment for most cancer patients. Despite its efficacy in eliminating cancer cells, a high percentage of chemotherapy patients eventually relapse or suffer progression of the disease. Immunosurveillance is capable of recognizing and eliminating continuously arising transformed mutant cells, and thus cancer immunotherapy is one of the emerging therapeutic strategies that harnesses the power of the immune system to eradicate chemotherapy-resistant cancerous cells. However, the adverse side effects of chemotherapy impede the therapeutic effects of immunotherapy. Our previous studies demonstrate that lymphoma patients are refractory to clinical immunotherapy because of chemotherapy-induced immune dysfunction. In addition, …

Evaluation Of Negative Energy And Mineral Balance In Periparturient Holstein-Friesian Cattle, Ameer Ahmed Abdelhameed

Open Access Dissertations

Most cows experience a state of negative energy and mineral balance during the periparturient period. This imbalance is a major problem in the dairy industry and it is more frequently seen in multiparous cattle due to their high milk production. A large amount of fat and protein is mobilized in order to address the energy deficit during the periparturient period. The ability to accurately monitor energetics and electrolytes status using accurate, rapid, and low cost point-of-care instruments will assist in optimizing animal health and productivity.

This dissertation contains three studies that evaluated point-of-care instruments for measuring blood and plasma glucose, …

Investigating The Role Of The Basic Helix-Loop-Helix Transcription Factor Mist1 In Pancreatic Diseases, Anju Karki

Open Access Dissertations

Acinar cells of the exocrine pancreas are dedicated to synthesize, package and secrete immense quantities of pro-digestive enzymes to maintain proper metabolic homeostasis for the organism. Dysregulation of enzyme secretion in acinar cells can give rise to exocrine diseases including acute pancreatitis (AP), a disease that targets acinar cells, leading to acinar-ductal metaplasia (ADM), inflammation and fibrosis—events that can transition into the earliest stages of pancreatic ductal adenocarcinoma (PDAC). The focus of this thesis is to interrogate transcriptional regulatory networks that are susceptible to AP and the role that these networks play in acinar cell and exocrine pancreas responses. The …

Influence Of The 3d Microenvironment On Glioblastoma Migration And Drug Response, Ruth Marisol Herrera Perez

Open Access Dissertations

Glioblastoma (GBM) is a highly invasive brain cancer characterized by poor prognosis. Despite significant efforts by the basic and clinical research community our understanding of GBM progression and recurrence has been incremental. Improvements in therapeutic response have been dismal, and GBM continues to be the deadliest tumor of the central nervous system, with patient average survival rate of 12 months. Synergistic relationships that the tumor cells establish with the brain microenvironment have been proven fundamental for successful tumor progression and maintenance. Yet, many in vitro GBM studies are performed in formats that fail to recapitulate the most essential component of …

Alternative Regulation Of Myc In Lung Cancer, Patrick N. Backman

Open Access Theses

Lung cancer is the leading cause of cancer deaths in the United States, accounting for 27% of all cancer induced deaths1. In an attempt to create a effective targeted therapy for the treatment of lung cancer, a strategy used to treat an activated KrasG12D/+;p53 R172H/+ transgenic lung cancer mouse model was to deliver a known tumor suppressive microRNA (miRNA) to stop tumor growth. The tumor suppressive miRNA let-7 was lentivirally delivered in the form of its primary transcript, pri-let-7a-1, and resulted in increased lung size and inflammation compared to lungs exposed to a control lentivirus. It was identified …

The Effects Of Acidified Pepsin On Porcine Vocal Fold Tissue: Developing A Porcine Model Of Laryngopharyngeal Reflux Disease, Abigail Cox Durkes

Open Access Dissertations

Approximately 7.5 million Americans are affected by a voice disorder. In the last year, 7.2% of people missed one or more days of work due to a voice problem. For professional voice users, such as teachers, the rate increases to 20% and an annual cost of $2.5 billion. Voice disorders are complex and multi-faceted, as well as difficult to diagnose and treat. Prospective animal studies are necessary to study the pathophysiology of voice disorders, optimize our understanding of laryngeal pathology, and improve treatment outcomes. The pig provides a unique opportunity to test hypotheses relating to laryngeal disease because porcine vocal …

Differences In Brainstem Level Encoding Of Am And Fm Signals In A Rat Model For Dyslexia, Stephen Anthony Chabot

Open Access Theses

Developmental dyslexia is a language learning disorder that affects a significant portion of the population. Many subjects who suffer from dyslexia show auditory processing deficits as children, some of which persist into adulthood, which impair their ability to learn one or more aspects of language. There is evidence that some types of training can correct the auditory processing deficits and bring the subject to a normal reading or speaking proficiency for their age group. One common rodent model for dyslexia is the cortical freeze lesion model. This model induces a lesion in the rat cortex similar to the microgyria present …

Review Of The Pathogenesis And Treatment Of Acute Spinal Cord Injury And Investigation Into The Use Of Urine 3-Hpma As A Novel Biomarker Of Secondary Injury After Acute Spinal Cord Injury In The Dog, Andrea Sangster

Open Access Theses

Acute spinal cord injury (ASCI) has two pathophysiological stages of injury: the primary injury and the secondary injury cascade. Primary injury includes the initial or mechanical insult to the spinal cord. Secondary injury is a cascade of biochemical events that propagates damage of adjacent, healthy tissue increasing the overall volume of spinal cord tissue that is affected. Acrolein is a toxic byproduct of lipid peroxidation produced during secondary injury. A metabolite of acrolein-glutathione adduct found in urine, 3-HPMA, has recently been shown to increase after spinal cord injury in a rat model. The aim of our study was to apply …

The Effects Of Heat Stress On Immunity In Laying Hens And Dairy Cattle, Rebecca Ann Strong

Open Access Theses

With the increase in global climate change and the population growth driving the high demand for additional food production, heat stress (HS) is a major concern in the livestock industry across all species. Animals experience HS when exposed to high environmental temperatures outside their thermal neutral zone. The level of the effects can vary due to the length and intensity of HS to which the animal is exposed to. In experiment one, laying hens with access to cooled perches during HS had a lower heterophil to lymphocyte ratio compared to the control hens after 4 h of acute heat stress, …

Cut-Off Values For Gait Variables To Detect Forelimb Lameness In Individual Dogs, Jennifer G. Carr

Open Access Theses

The objective of this study was to characterize kinetic and kinematic variables in dogs with forelimb lameness and determine lameness cutoff values of gait variables using ROC analysis with observational gait analysis (OGA) as reference. Twenty client-owned dogs with unilateral lameness were included. Dogs underwent orthopedic exam, including OGA, and instrumented gait analysis (IGA; kinetic and kinematic analysis). Kinetic variables with the highest accuracy were PVF and %WD with an area under the curve (AUC) of 0.73 and 0.92, respectively. Optimal cutoff value for PVF and %WD were ≤ 10.6 (sensitivity 70% and specificity 75%) and ≤ 29.7 (sensitivity 90% …

1,25-Dihydroxyvitamin D Alters Lipid Metabolism And Epithelialto- Mesenchymal Transition In Metastatic Epithelial Breast Cancer Cells, Alle Nicole Barnard

Open Access Theses

Evidence suggests that high vitamin D status (marked by serum 25-hydroxyvitamin D, 25(OH)2 D) is associated with a decreased risk of breast cancer. It has been established that 1,25-dihydroxyvitamin D (1,25(OH) 2 D) can alter glycolysis and the Krebs cycle of breast cancer cells (Jiang et al., 2010; Zheng et al., 2013) but little information is available on 1,25(OH) 2 D's alterations of lipid metabolism in breast cancer cells. Thus, the current research investigates if there was an effect of 1,25(OH) 2 D on proteins that regulate lipid metabolism in MCF10A, MCF10A-ras, MCF10CA1h, and MCF10CA1a epithelial breast cancer cells. While …

Pharmacokinetics And Toxicity Of The Novel Oral Demethylating Agent Zebularine In Laboratory And Tumor Bearing Dogs, Christopher Michael Fulkerson

Open Access Theses

The aim of this thesis is to investigate the pharmacokinetics and toxicity of the novel oral demethylating agent zebularine (zeb) in laboratory dogs and tumor bearing dogs. This thesis focuses on the application of this therapeutic strategy in dogs with naturally occurring invasive transitional cell carcinoma (InvTCC), which serve as a relevant model of the human disease.

DNA hypermethylation in the promoter region is a common epigenetic change in cancer that silences tumor suppressor genes. Zeb is an oral cytidine analog that acts as a demethylating agent. Zeb has been investigated extensively in vitro as well as in mice, rodents …

Pharmaceuticals And Personal Care Products: Emerging Contaminants In Aquatic Ecosystems, Jenny E. Zenobio

Open Access Theses

In recent years, the presence of pharmaceuticals and personal care products (PPCPs) in aquatic systems has led to research on their fate and effects. PPCPs have been found in mixture in wastewater effluents, surface, ground, and drinking water at low concentrations from areas of intense urbanization. Although adverse effects to human health from the current environmental concentrations are unlikely, the impacts to ecological receptors are not clear. We performed field and laboratory studies to quantify and evaluate effects of PPCPs on fish. First, a field study was conducted at the Baca National Wildlife Refuge, Colorado (2010-2012) because a portion of …

Effects Of Hearing Aid Amplification On Robust Neural Coding Of Speech, Jonathan Daniel Boley

Open Access Dissertations

Hearing aids are able to restore some hearing abilities for people with auditory impairments, but background noise remains a significant problem. Unfortunately, we know very little about how speech is encoded in the auditory system, particularly in impaired systems with prosthetic amplifiers. There is growing evidence that relative timing in the neural signals (known as spatiotemporal coding) is important for speech perception, but there is little research that relates spatiotemporal coding and hearing aid amplification.

This research uses a combination of computational modeling and physiological experiments to characterize how hearing aids affect vowel coding in noise at the level of …

Omega-3 Fatty Acid Supplementation In The Management Of Chronic Lower Airway Inflammatory Conditions In Horses, Nora Nogradi

Open Access Theses

Chronic lower airway inflammatory diseases, such as recurrent airway obstruction (RAO) and inflammatory airway disease (IAD) are common in horses. RAO and IAD present many similarities with asthma in people. Based on studies in human asthma, omega - 3 polyunsaturated fatty acid (PUFA) supplementation has been proposed to improve clinical signs in horses with chronic lower airway inflammatory disease. The purpose of this study was to evaluate the clinical efficacy of an omega-3 PUFA containing equine feed supplement (Aleira^TM) in horses with chronic lower airway disease. The study consisted of two separate experiments. First, a pilot study was …