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Impact Of Dietary Modification On Aflatoxicosis In Poultry, Xi Chen Dec 2016

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, …


Nanoparticle Toxicity And Molecular Mechanisms In Fish: A Case Study With Silver Nanoparticles, Jiejun Gao Dec 2016

Nanoparticle Toxicity And Molecular Mechanisms In Fish: A Case Study With Silver Nanoparticles, Jiejun Gao

Open Access Dissertations

Nanoparticles (NPs) are widely used in a myriad of commercial and industrial products making their entry to the environment a likely event. NPs have unique physical-chemical properties that result from their small size and high surface area to volume ratio, making them highly reactive and potentially toxic. In Chapter 1, we summarize the effects and mechanisms of metal-based NPs on the vascular system. In vitro studies have shown that NPs are anti-angiogenic because they cause inflammation, oxidative stress, and apoptosis of endothelial cells resulting in increased permeability and decreased proliferation and migration. Whole animal studies examining the effects of NPs …


The Impact Of Tickling Rats On Human-Animal Interactions And Rat Welfare, Megan Renee Lafollette Dec 2016

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 Dec 2016

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 Aug 2016

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 …


Manufacturer Perspectives On Content Transparency And Material Health In The Us Building Products Industry, Alexandra A. Muller Aug 2016

Manufacturer Perspectives On Content Transparency And Material Health In The Us Building Products Industry, Alexandra A. Muller

Open Access Theses

Flawed U.S. federal regulation of chemicals has resulted in a materials market that undervalues human and environmental health in favor of the more traditional attributes of price, performance and aesthetics. In the building products industry, global, dynamic supply chains and proprietary information concerns further complicate the task of assessing the material health of products.

Voluntary material health programs in the green building industry are intended to incentivize the manufacture and selection of safer products by getting companies to gather and assess ingredient, hazard and risk information from their supply chain. Building product manufacturers considered early adopters of the main material …


The Interactive Effects Of Pesticide Exposure And Infectious Disease On Amphibian Hosts, Katherine M. Pochini Aug 2016

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 Aug 2016

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 …


Immune Modulating Functions By Soypeptide Lunasin In Cancer Immunotherapy, Chun-Yu Tung May 2016

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 Apr 2016

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 Apr 2016

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 Apr 2016

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 Mar 2016

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 Pathological Role Of Acrolein In Experimental Autoimmune Encephalomyelitis And Multiple Sclerosis, Melissa A. Tully Apr 2015

The Pathological Role Of Acrolein In Experimental Autoimmune Encephalomyelitis And Multiple Sclerosis, Melissa A. Tully

Open Access Dissertations

Multiple sclerosis (MS) is an autoimmune demyelinating neuropathy that affects nearly 2.5 million people worldwide. Despite substantial efforts, few treatments are currently available largely due to limited knowledge of pathogenic mechanisms underlying the disease. The immune-inflammatory nature of the pathology has prompted investigation of the role of oxidative stress in disease development and progression; however targeting reactive oxygen species for neutralization has had marginal success therapeutically, suggesting that an alternate oxidative stress-related target would prove beneficial. Recently, our lab has implicated acrolein, a highly reactive aldehyde that is both a byproduct and catalyst of lipid peroxidation, as a potential therapeutic …


A Novel In Vivo Tumor Oxygen Profiling Assay: Combining Functional And Molecular Imaging With Multivariate Mathematical Modeling, Chung-Wein Lee Apr 2015

A Novel In Vivo Tumor Oxygen Profiling Assay: Combining Functional And Molecular Imaging With Multivariate Mathematical Modeling, Chung-Wein Lee

Open Access Dissertations

Purpose: The objective of this study is to develop and test a novel high spatio-temporal in vivo assay to quantify tumor oxygenation and hypoxia. The assay implements a biophysical model of oxygen transport to fuse parameters acquired from in vivo functional and molecular imaging modalities. ^ Introduction: Tumor hypoxia plays an important role in carcinogenesis. It triggers pathological angiogenesis to supply more oxygen to the tumor cells and promotes cancer cell metastasis. Preclinical and clinical evidence show that anti-angiogenic treatment is capable of normalizing the tumor vasculature both structurally and functionally. The resulting normalized vasculature provides a more efficient and …


Physical Actvity In Pregnant Rat Dams Reduces Mammary Tumor Formation In Offspring, Leon Clah Apr 2015

Physical Actvity In Pregnant Rat Dams Reduces Mammary Tumor Formation In Offspring, Leon Clah

Open Access Theses

Breast cancer is the most frequently diagnosed cancer and a leading cause of cancer death among women. Lifestyle factors such as physical activity and diet play a role in attenuating the incidence of breast cancer. Current research is beginning to show that exercise during pregnancy can convey long term health benefits to offspring. In light of these studies, the goal of this project was to determine if maternal physical activity during pregnancy could lead to reduced mammary tumor development in female offspring. Towards this goal, female Sprague Dawley rats were divided into two groups, sedentary and exercise, with the exercise …


Effects Of Moderate-Level Sound Exposure On Behavioral Thresholds In Chinchillas, Maria Sandra Carbajal De Nava Apr 2015

Effects Of Moderate-Level Sound Exposure On Behavioral Thresholds In Chinchillas, Maria Sandra Carbajal De Nava

Open Access Theses

Normal audiometric thresholds following noise exposure have generally been considered as an indication of a recovered cochlea and intact peripheral auditory system, yet recent animal work has challenged this classic assumption. Moderately noise-exposed animals have been shown to have permanent loss of synapses on inner hair cells (IHCs) and permanent damage to auditory nerve fibers (ANFs), specifically the low-spontaneous rate fibers (low-SR), despite normal electrophysiological thresholds. Loss of cochlear synapses, known as cochlear synaptopathy, disrupts auditory-nerve signaling, which may result in perceptual speech deficits in noise despite normal audiometric thresholds. Perceptual deficit studies in humans have shown evidence consistent with …


Fuel Choice, Acute Respiratory Infection And Child Growth In Uganda, Onyekachi U. Aghasili Apr 2015

Fuel Choice, Acute Respiratory Infection And Child Growth In Uganda, Onyekachi U. Aghasili

Open Access Theses

This thesis seeks to explain the relationship between a household's choice of fuel and the health and nutrition outcomes of children below the age of 5 in Uganda. The first objective is to examine the association between the choice of fuel and the incidence of acute respiratory infection (ARI). The second objective is to measure the relationship between choice of fuel, ARI and nutrition outcomes of children. ^ I use data from the 2006 and 2011 Uganda Demographic and Health Surveys (UDHS). The total number of observations is 4,463. Data indicate that 94% of rural households in the DHS sample …


Baylisascaris Spp. In Non-Raccoon Procyonid Hosts And Assessment Of Potential Risk Of Human Exposure, Max Carlin Parkanzky Apr 2015

Baylisascaris Spp. In Non-Raccoon Procyonid Hosts And Assessment Of Potential Risk Of Human Exposure, Max Carlin Parkanzky

Open Access Theses

Baylisascaris procyonis (Bp) is a large roundworm of the common raccoon (Procyon lotor) which serves as the definitive host. Bp is an important cause of clinical larva migrans, including severe neurological disease, across numerous taxa including humans. Other procyonids, as well as occasionally dogs, can act as definitive hosts for this or other Baylisascaris spp. Many of these animals are becoming more common as household pets, posing a risk to people who come in contact with these animals. We have investigated whether patent Baylisascaris spp. infection exists in captive non-raccoon procyonids and if humans who contact these animals …


Beta-Lactam Antimicrobial Dosing Optimization In Obese Patients Compared To Non-Obese Patients Using Population Pharmacokinetic/Pharmacodynamic Approach, Eun Kyoung Chung Apr 2015

Beta-Lactam Antimicrobial Dosing Optimization In Obese Patients Compared To Non-Obese Patients Using Population Pharmacokinetic/Pharmacodynamic Approach, Eun Kyoung Chung

Open Access Dissertations

Obesity is a significant global health problem and has been associated with altered pharmacokinetics and pharmacodynamics of many drugs. However, little is known regarding the effect of obesity on the pharmacokinetics and pharmacodynamics of many broad-spectrum, beta-lactam antibiotics such as piperacillin/tazobactam, meropenem, and cefepime. The objective of this study is to evaluate the population pharmacokinetics and pharmacodynamics of piperacillin/tazobactam, meropenem, and cefepime in hospitalized obese patients in order to determine dosing regimens that provide similar exposures between obese and non-obese patients. ^ For piperacillin/tazobactam, a retrospective analysis was conducted using prospectively collected serum concentration-time data from two previous studies (Study …


Consumer Inferences Of Corporate Social Responsibility (Csr) Claims On Packaged Foods, Gaeul Kim Apr 2015

Consumer Inferences Of Corporate Social Responsibility (Csr) Claims On Packaged Foods, Gaeul Kim

Open Access Theses

With the growing public demands in Corporate Social Responsibility (CSR) of the food industry, CSR claims have begun to appear on food packages, as companies started communicating their CSR initiatives to consumers. Although food packages emerged as an important CSR communication tool, consumers' processing of CSR claims and the effects of these claims on product evaluations still remain unknown. In this regard, the present study carries two important research questions. First, do non-health/nutrition-related CSR claims influence consumers' product evaluations, such as perceived health benefits or tastes? If so, how does the effect of CSR claims differ by type of CSR …


Evaluating Breast Cancer Stem Cell Response To Antiangiogenic Therapy, Connor J. Holloway Apr 2015

Evaluating Breast Cancer Stem Cell Response To Antiangiogenic Therapy, Connor J. Holloway

Open Access Theses

Angiogenic inhibitors function by blocking tumor cell signals used to recruit host tissue vasculature to the tumor site, thereby depriving the cancer of the nutriment needed for further expansion. The development and implementation of angiogenic inhibitors in conjunction with standard chemotherapy agents has increased progression-free survival but not overall patient survival. It is hypothesized that chronic exposure to large doses of AAT drugs worsens hypoxic conditions within the tumor mass, selectively stimulating aggressive cancer stem cell populations to grow and proliferate. ^ In this study, the expression of the CSC biomarkers ALDH1, DLL1, and EpCAM were evaluated in breast cancer …


Mach: A Model For Explaining Molecular And Cellular Mechanisms, Caleb M. Trujillo Jan 2015

Mach: A Model For Explaining Molecular And Cellular Mechanisms, Caleb M. Trujillo

Open Access Dissertations

Biologists use mechanistic explanations to understand behaviors of the immense complexity of molecular and cellular systems. In undergraduate biology courses, students are expected to explain molecular and cellular mechanisms, but teaching this skill presents many challenges due to the highly abstract, intangible nature of the cellular world, the influence of everyday language, and the tendency of students to overestimate how much they can explain. Therefore, across three studies this dissertation addresses these obstacles to teach undergraduate biology students to explain molecular and cellular mechanisms. ^ The first step was to model how biology experts explain molecular and cellular mechanisms, and …


Show Horse Welfare, Melissa A. Voigt Jan 2015

Show Horse Welfare, Melissa A. Voigt

Open Access Dissertations

In recent years there has been an increase in the public's attention to situations where trainers, owners, and handlers have compromised the well-being of show horses for the sake of winning. These situations may be due to training negligence or naivety of individuals working with the horse. Either way, due to these incidents, increasing pressure has been placed on the horse industry to address show horse welfare. The purpose of this research was to expound on the welfare of stock-type show horses through the perspective of those directly involved; considering the understanding of welfare, the value placed on welfare, and …


Host Cell Death In Legionella Pneumophila Pathogenesis And Immunity, Wenhan Zhu Oct 2014

Host Cell Death In Legionella Pneumophila Pathogenesis And Immunity, Wenhan Zhu

Open Access Dissertations

Legionella pneumophila is an intracellular pathogen that causes a severe, atypical pneumonia termed Legionnaires' disease. Upon entering the host cell, L. pneumophila resides in a membrane-bound vacuole, in which the bacterium evades lysosomal fusion and replicates. The establishment of the vacuole requires the Dot/Icm (Defect in organelle trafficking/ intracellular multiplication) transport system, which translocates a large number of substrates into host cells to re-orchestrate various cellular processes, such as intracellular trafficking, protein synthesis and host cell death pathways. Therefore, a key step in understanding the biology of Legionella is to dissect the mechanisms of action of the Dot/Icm substrates. By …


Quantitative Modeling Of Spatiotemporal Systems: Simulation Of Biological Systems And Analysis Of Error Metric Effects On Model Fitting, James Hengenius Oct 2014

Quantitative Modeling Of Spatiotemporal Systems: Simulation Of Biological Systems And Analysis Of Error Metric Effects On Model Fitting, James Hengenius

Open Access Dissertations

Understanding the biophysical processes underlying biological and biotechnological processes is a prerequisite for therapeutic treatments and technological innovation. With the exponential growth of computational processing speed, experimental findings in these fields have been complemented by dynamic simulations of developmental signaling and genetic interactions. Models provide means to evaluate "emergent" properties of systems sometimes inaccessible by reductionist approaches, making them test beds for biological inference and technological refinement.^ The complexity and interconnectedness of biological processes pose special challenges to modelers; biological models typically possess a large number of unknown parameters relative to their counterparts in other physical sciences. Estimating these parameter …


The Impact Of An Omega-3 Enriched Diet On Hyperactivity And Biochemistry In An Animal Model For Attention-Deficit/Hyperactivity Disorder, Nadine M. Hammoud Oct 2014

The Impact Of An Omega-3 Enriched Diet On Hyperactivity And Biochemistry In An Animal Model For Attention-Deficit/Hyperactivity Disorder, Nadine M. Hammoud

Open Access Theses

Attention-deficit/hyperactivity disorder (ADHD) is the most diagnosed behavioral disorder in children. It affects around 5% of children worldwide and 11% of children in the United States, with rates increasing. Pharmaceutical treatments, such as amphetamines and methylphenidates, are not effective for everyone and are known to have unwanted side effects. While the etiology of the disorder is not yet fully understood, there are clear genetic and environmental components. Nutritional insufficiencies have recently become a popular environmental risk factor under investigation. Essential fatty acids (EFA), omega-3 polyunsaturated fatty acids (PUFA) in particular, are needed for proper brain development and function. Our lab …


The Effects Of Heat Stress On Immunity In Laying Hens And Dairy Cattle, Rebecca Ann Strong Oct 2014

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, …


African Starchy Foods, Gastric Emptying, And Starch Digestion In Malian Stunted Children, Fatimata Cisse Oct 2014

African Starchy Foods, Gastric Emptying, And Starch Digestion In Malian Stunted Children, Fatimata Cisse

Open Access Dissertations

Starch serves as the main energy source in cereal and tuber-rich diets, and its glycemic response profile has been associated with health-related conditions. Sorghum and millet are known to have relatively low starch digestibility, a potentially desirable property for controlling blood glucose response and providing sustained energy. Gastric emptying rates of traditional sorghum and millet-based African foods of the Sahelian region (couscous, thick and thin porridges made from millet and/or sorghum) were compared to those of non-traditional "modern" foods that are mostly consumed in urban areas using a non-invasive 13C-labelled octanoic acid breath test in healthy volunteers. The obtained results …


Prediction Of Parturition And Dystocia In Holstein-Friesian Cattle, And Cesarean Section In Dystocic Beef Cattle, Wen Han Mark Hiew Oct 2014

Prediction Of Parturition And Dystocia In Holstein-Friesian Cattle, And Cesarean Section In Dystocic Beef Cattle, Wen Han Mark Hiew

Open Access Dissertations

Dystocia is a major problem in the dairy industry as it causes livestock and economic loss. It is more frequently seen in primiparous cattle compared to their multiparous counterparts due to their smaller stature and the slow maturation of pelvic dimensions. In some instances, human intervention of the parturition process is imperative to avoid pain, injury, and mortality of the neonate and the dam. The ability to accurately predict dystocia and the time of parturition will ensure that timely assistance can be given to animals that are of high risk of dystocia.^ The present thesis contains four studies that explore …