Animal Sciences Commons^™

Leptin Regulates The Expression Of Autophagy-Related Genes In Chickens, Peter Olawale Ishola

Graduate Theses and Dissertations

Autophagy or cellular self-digestion, a lysosomal degradation pathway that is conserved from yeast to human, plays a key role in recycling cellular constituents, including damaged organelles. It also plays a pivotal role in the adaptation of cells to a plethora of distinct stressors including starvation. Autophagy has been extensively studied in mammals and yeast, but little is known in avian species. Thus, the major objective of the present study was to determine the effects of leptin on autophagy-related genes in chicken hypothalamus, muscle and liver. Leptin is an adipocytokine that is mostly produced by white adipose cells in mammals (as …

Spring Migration Ecology Of American Woodcock (Scolopax Minor) In The Central Management Region Of The United States, Cari Elizabeth Sebright

Graduate Theses and Dissertations

American woodcock (Scolopax minor) is a migratory game bird in population decline since the start of monitoring in 1968. Researchers are interested in gaining knowledge of spring migration ecology to improve migration habitat and mitigate population decline. I captured six woodcock with mist and hand nets on nocturnal habitat and marked them with VHF (very high frequency) transmitters in northern Arkansas. I documented the distance they traveled between nocturnal and diurnal habitats (n=27), and documented diurnal vegetation characteristics at sites used (n=25). I found that woodcock moved an average of 370 m (SE 25.31 m) with the longest movement being …

Reduction Of Campylobacter Jejuni On Chicken Wingettes By Treatment With Caprylic Acid, Chitosan Or Protective Cultures Of Lactobacillus Spp., Ann Nicole Woo-Ming

Graduate Theses and Dissertations

Poultry is one of the main sources of protein in the United States and in 2014 Americans ate approximately 100 lbs per person. However, consumption of poultry products is strongly associated with foodborne illness from Campylobacter. In the first study, chitosan, caprylic acid and their combination were evaluated as a coating treatment for the reduction of Campylobacter jejuni on poultry products. For the initial screening trials, chitosan of three different molecular weights (15-50 kDa, 190-310 kDa and 400-600 kDa) was evaluated at three concentrations (0.5%, 1.0%, 2.0%) and separately, caprylic acid was tested at 0.5%, 1.0% and 2.0% using chicken …

Calorimetry And Body Composition Research In Broilers And Broiler Breeders, Justina Victoria Caldas Cueva

Graduate Theses and Dissertations

Indirect calorimetry to study heat production (HP) and dual energy X-ray absorptiometry (DEXA) for body composition (BC) are powerful techniques to study the dynamics of energy and protein utilization in poultry. The first two chapters present the BC (dry matter, lean, protein, and fat, bone mineral, calcium and phosphorus) of modern broilers from 1 – 60 d of age analyzed by chemical analysis and DEXA. DEXA has been validated for precision, standardized for position, and equations and validations developed for chickens under two different feeding levels. These equations are unique to the machine and software in use. Research in broilers …

Transcriptomics Of Chicken Primordial Germ Cells, Nhung Thi Nguyen

Graduate Theses and Dissertations

Chicken primordial germ cells (PGCs) are derived from extraembryonic tissue of the embryo and first appear at stage X of development. They enter the bloodstream and migrate to the genital ridge, unite with somatic tissue to form a developing gonad, and then differentiate to sperm or ova (Fujimoto et al., 1976). Understanding molecular features of both male and female PGCs not only clarify the differentiation mechanism of such cells toward different germ lines, but will also help in selecting for highly productive types of commercial chicken. Most previous studies focused on the location of PGCs (Eyal-Giladi et al., 1981; Swift …

Broiler Breeder Mating Behavior And The Effects Of Pre-Incubation Embryo Integrity Modifications On Broiler Performance, Emily Kathryn Lhamon

Graduate Theses and Dissertations

Modern broiler breeders have been observed displaying significantly less mating behaviors than their ancestral fowl. Effective mating behavior translates into fertile hatching eggs that ultimately become broilers processed for market. The poultry industry has made significant changes in genetics, environment, housing, and diets of commercial poultry. However, there are some concessions made in genetic selection and streamlined management to produce larger, fast-growing, efficient birds. Aggression in broiler breeder males is believed to be a sign of high fertility. However, highly aggressive males pose a threat to the welfare of their flock mates, and may also impede frequency of mating and …

Autophagy And Its Potential Role In Stress And Feed Efficiency Using Avian Lines, Alissa Laura Piekarski

Graduate Theses and Dissertations

Autophagy is a highly conserved cellular mechanism that is responsible for the degradation and recycling of damaged organelles. Recently, autophagy has been involved in critical roles during overall development of the organism and degradation of damaged cellular components. This pathway has witnessed dramatic growth in the last few years and has been extensively studied in yeast and mammals, however, there is a paucity of information in avian (non-mammalian) species. First, we characterized genes involved in the autophagy pathway in male and female Jungle Fowl to determine gender and tissue specific differences. Secondly, tissue and genotype differences in Japanese quail selected …

Evaluation Of Bacillus Spp Candidates For Aflatoxin B1 Biodegradation In Broiler Chickens, Rosario Galarza Seeber

Graduate Theses and Dissertations

Poultry health has been traditionally maintained by hygenic measures, vaccinations, and the use of antibiotics. Modern husbandry management considers the use of probiotics as a natural way to protect birds against many everyday pathogens. Different strains of Bacillus spp. have proved to have beneficial effects in poultry production. However, the most used bacterium in commercial probiotics is Lactobacillus, a vegetative cell. In contrast, Bacillus spp are bacterial spores, highly resistant to harsh conditions, which makes them preferable, in some cases, to Lactobacillus because of shelf life and storage conditions. There is published information regarding mycotoxin detoxification by bacteria. Mycotoxins are …

In Vivo Periodical Monitoring Of Immune Cell Infiltration In Response To Feathers And Intramuscular Injection Of Ionps Using The Pulp (Dermis) Of Growing Feathers As Test Site Tissue In Chickens, Olfat Taleb Alaamri

Graduate Theses and Dissertations

The applications of nanoparticles are growing, but little is known about their interactions with the immune system as most studies did not use suitable in vivo test systems. The purpose of these studies was to investigate the utility of chicken growing feathers as an in vivo test site for iron oxide nanoparticle (IONP) interactions with the immune system. The first objective of this study was to monitor leukocyte infiltration into the growing feather pulp upon the administration of IONP and IO-mIgG preparations. The second objective was to test the utility of IONPs as vaccine adjuvants by monitoring primary and memory …

The Effect Of Alternative Fertilization And Application Time On Voluntary Intake Of Forages, Jessica Clark

Graduate Theses and Dissertations

Dairy slurry and poultry litter have increased in popularity as fertilizers in the agriculture industry. However, residual effects of these manures on voluntary intake of forages from subsequent harvests are not well known. The objectives of this two part study were to determine if moisture level of alfalfa silage and the use of dairy slurry as a fertilizer have an effect on intake and digestibility by sheep, and if forage species and the use of poultry litter as a fertilizer have an effect on intake by horses. Eighteen ewes (47.6 ± 5.34 kg) were used in experiment 1 and were …

Investigations Into The Cross-Infectivity Of Nematode Parasites Of Cattle And Sheep, Eva Marie Wray

Graduate Theses and Dissertations

The existence of anthelmintic resistance is not singular in parasite species, host species or geographic region. It has become a problem of worldly stature, especially when considering sheep nematodes. Recommendations have been modified from chemical-based control to multipart, managerial intervention. Compared with nematodes of cattle, the worldwide resistance of sheep nematodes to anthelmintic remedies is much more pronounced and urgent. As the resistance to essentially all anthelmintic classes approaches a cautionary level, the implementation of non-chemical controls has grown increasingly essential. Six-6 to 8 month old Holstein steer calves, six-5 month old Katahdin ram lambs and eight-5 month old Suffolk …

A Cradle To Farm Gate Life Cycle Analysis Of Land Use In U.S. Pork Production, William Benjamin Putman

Graduate Theses and Dissertations

The goal of this study was to conduct a detailed Life Cycle Assessment (LCA) of the U.S. live swine production supply chain to quantify land use requirements and to assess the impact associated with various ration compositions. The functional unit was defined as one kilogram (2.2 pounds) of live swine at the farm gate, ready for transport to the abattoir. This assessment focused on the three highest producing USDA regions, which encompassed the Midwest (Regions 5 and 7) and the Southeast (Region 4), representing 86% of U.S. market hog production.

First, a literature review was conducted to summarize the most …

Life Cycle Assessment Of Alternative Swine Management Practices, Prathamesh Avadhut Bandekar

Graduate Theses and Dissertations

Life Cycle Assessments (LCAs) are quantitative analyses of complex systems for evaluation of impacts and risk associated with management decisions. LCAs can be effective tools for determining comparative advantages of management strategies across specific impact concern. In this study, life cycle assessments of pork production management alternatives was performed. The alternative management practices included in this study were production of entire males (boars), use of pens for gestation housing, immunocastration, production without growth promoting antimicrobials, production without growth promoting and preventive antimicrobials, and production without ractopamine. These LCAs evaluated the impact of each management strategy on greenhouse gas emission (GHG), …

Grass Finishing Systems For Lambs, Erin Leigh Smyth

Graduate Theses and Dissertations

There is strong interest in sustainably produced meat. Grass-fed lamb could fulfill this market by reducing off-farm inputs. The objective was to examine the effect of grass-finishing or minimal supplementation on performance of lambs in the southeastern US. Katahdin lambs born in October 2013 and 2014 and February 2014 were weaned in January 2014/2015 and May 2014, respectively. Lambs were blocked by gender (fall; winter included only ram lambs) and randomly assigned to receive no (NON) or grain co-product supplement (SUP; 15% CP) at 0.5% of BW/d. Lambs were rotationally grazed on predominantly grass. Body weight, fecal egg counts (FEC), …

Novel Biomarkers For Calcium And Phosphorus Metabolism In Breeder Hens And Broilers, Andrew Dick Magnuson

Graduate Theses and Dissertations

Broiler breeder hens are subject to the dual expectation to not only maintain a high production of eggs for an extended time period, but to produce eggs which can support the life of chicks which will be used for either meat production or as parent stock. Egg fertility and hatchability are heavily influenced by the thickness of the egg shell, the mineral calcium carbonate shell of the egg necessary for protecting the embryo growing inside. Many factors affect egg shell quality including age of the hen, diet, environmental conditions, genetic strain, stress, disease, and nutrition. Laying hens will mobilize calcium …

Water Consumption Behavior In Broilers, David Harold Mccreery

Graduate Theses and Dissertations

A series of trials were conducted to analyze broiler water consumption behaviors under commercial conditions. The first trial was to quantify the number of broilers drinking at times of peak water demand. Birds were evaluated at time intervals of 5, 10, 15, 30, 45, and 60 minutes from the start of the light period to establish the percentage birds having consumed water by that point in time. Significant differences were found by bird age in the 5, 10, and 15 minute intervals, however there were no significant differences in the percentage of birds having consumed water in the 30, 45, …

Effect Of Feeding Regimen And Age On Lipid Metabolism In Broiler Breeder Hens And Progeny, Nirun Boonsinchai

Graduate Theses and Dissertations

Age of hens and feed allocation can affect egg yolk lipid compositions which in turn directly relate to chick quality. A series of experiments were conducted to determine the effects of age and feeding programs on lipid metabolism in breeder hens and progeny. In the first trial, the rate of yolk absorption and fatty acid profiles in the yolk were compared among 28, 35, and 49wk old hens. The results revealed that the rate of yolk absorption was higher, but the absolute amount of fatty acids absorbed was lower in young hens than in the old hens. The second trial …

The Ability Of Select Probiotics To Reduce Enteric Campylobacter Colonization In Broiler Chickens, Sandip Shrestha

Graduate Theses and Dissertations

Campylobacter is the leading cause of foodborne illness worldwide and is often associated with consumption and/or mishandling of contaminated poultry products. Probiotic use in poultry has been an effective strategy in reducing other enteric foodborne pathogens but not consistently for Campylobacter. As Campylobacter resides and utilizes intestinal mucin for growth, isolates selected on the basis of mucin utilization might be a strategy to screen for efficacious probiotic bacterium. In this study, bacterial isolates demonstrating increased growth rates in mucin, in vitro (trials 1 or 2), or isolates demonstrating a reduction of Campylobacter counts when co-incubated with mucin, in vitro (trials …

Meat Quality Of Broiler Breast Fillets With White Striping And Woody Breast Muscle Myopathies, Vishwesh Vijay Tijare

Graduate Theses and Dissertations

The global poultry industry has been faced with emerging broiler breast meat quality issues known as white striping and woody breast. Two experiments were conducted to evaluate effects of white striping and woody breast hardness on meat quality traits in broiler breast fillets. Birds were processed at 8 wk (Exp.1) and at 6 and 9 wk of age (Exp.2), whereas deboning was carried out at 4 and 2 h postmortem in Exp.1 and 2, respectively. Fillets were categorized as: normal for both white striping and woody breast (NORM); mild for white striping and woody breast (MILD); severe for white striping …

Differential Gene Expression Between Two Developmental Stages Of The Gené'S Organ In The Cattle Fever Tick, Rhipicephalus (Boophilus) Microplus, Jason P. Tidwell

Theses and Dissertations - UTB/UTPA

The southern cattle fever tick (SCFT), Rhipicephalus microplus, is considered the most economically important ectoparasite of livestock worldwide and ranks sixth among the most pesticide resistant arthropods globally. This single-host hard tick is a vector of the infectious agents causing bovine babesiosis and anaplasmosis. The estimated impact of these SCFT-borne diseases on the livestock industry in the world is $7 billion annually. This project focuses on the Gené’s organ and addresses the need to identify novel targets that can serve as the basis for sustainable SCFT control strategies. Wax secreted by the Gené’s organ protects tick eggs from desiccation, bacterial …

Poultry Production Messaging: A Content Analysis Of Three National Newspapers From 1994 To 2014, Stuart Estes

Graduate Theses and Dissertations

Consumers are increasingly concerned with the use of antibiotics and hormones in poultry production, and the news media is the primary way consumers gain knowledge about this subject. This study assessed articles about antibiotic and hormone use in poultry production from the New York Times, USA Today, and the Wall Street Journal from 1994 to 2014. This study employed a content analysis methodology to assess selected articles (n = 139) for key messaging about antibiotic and hormone use in poultry production, article tone, article framing, and article journalistic quality. Data gathered from key messages were assessed for emergent themes that …

Investigations Into The Incidence And Control Of Selected Parasites And Pathogens Which Infect Arkansas Horses, Stephanie Ann O'Berg Rainbolt

Graduate Theses and Dissertations

Parasite control is an important aspect of health management of horses, particularly the control of gastrointestinal (GI) parasites. Recently, treatment recommendations have involved selective use of anthelmintics in horses with fecal egg counts (FEC) greater than a specified threshold. The objectives of this study were; (1) to determine the prevalence of helminths in our area by egg and L3 determinations, (2) to determine if certain horses maintained low FEC, therefore eliminating the need to treat them on a year-round basis and (3) to determine the effectiveness of four common treatments (moxidectin, ivermectin (pioneer and generic), fenbendazole and pyrantel tartrate) via …

Electrostatic Atomization Of Antimicrobial Treatments On Ground Beef Processing, Instrumental Color, Sensory Color, Taste And Aroma Characteristics, Jorge Abraham Marcos

Graduate Theses and Dissertations

The general objectives of this research were to evaluate the interaction effects of sixteen different antimicrobial treatments throughout seven days of display on physical, chemical and sensory characteristics of ground beef patties, when compared to an un-treated control. Antimicrobial treatments included: fumaric acid, malic acid, octanoic acid, decanoic acid, sodium propionate, propionic acid solution, potassium lactate/diacetate blend, sodium benzoate, hexanoic acid, pyruvic acid, levulinic acid, lactic acid/ citric acid blend, sodium diacetate, lemon juice and acetic acid. Prior to grinding, beef trimmings (80/20) were electrostatically sprayed with antimicrobial treatment solutions. Ground beef was processed into meat patties and sampled for …

Effects Of Crystalline Amino Acid Supplementation Of Reduced Crude Protein (Rcp) Diet On Net Energy Basis On Growing-Finishing Swine, Daniel Cook

Graduate Theses and Dissertations

Barrows and gilts (n=210) were used to test the effects of crystalline amino acid (AA) supplementation of reduced crude protein (RCP) diets formulated on a net energy basis on quality characteristics of the LM from growing-finishing pigs. Pigs were blocked by weight, and pens (3 barrows and 3 gilts/pen) within each block were assigned randomly to either corn-soybean meal diets (C) or 1 of 3 RCP diets and added crystalline AA levels for the dietary treatments during each feeding phase. During the last 3-wk feeding phase, 10 ppm of ractopamine were included in all diets. At slaughter and after a …

Efficacy Of Beta-Resorcylic Acid To Reduce Campylobacter Jejuni In Pre-Harvest And Post-Harvest Poultry, Basanta Raj Wagle

Graduate Theses and Dissertations

Campylobacteriosis is one of the leading foodborne illnesses in United States, and is associated with the consumption of poultry and poultry products. Reducing Campylobacter in these species will reduce the burden of this disease. Unfortunately, most strategies employed to reduce Campylobacter in poultry have either not been successful or produced inconsistent results. One potential control strategy is the use of β-resorcylic acid (BR), a phytophenolic compound classified by the US FDA as "Everything Added to Food in the United States" (EAF 3045) and is therefore deemed safe for consumption. This compounds has antibacterial activity against Salmonella, however, its efficacy to …

Divergent Selection For Four-Day Relative Breast Yield And The Effect Of Thermal Manipulations On Growth Characteristics On Lines Selected For Different Processing Dates., James Grant Mason

Graduate Theses and Dissertations

Genetic selections currently utilized in the poultry industry have been highly successful in promoting broiler growth rate and yield. However, these selections may have come at the expense of broiler physiology, as evidenced by an increase in physiological disorders. To address this experimentation was undergone to develop a novel method of selection to promote growth with minimal physiological impact and to assess how a new embryonic technique affects growth in broiler lines exhibiting different growth rates.

In the first experiment, a random bred control (RAN) broiler line was divergently selected for four-day relative breast yield (BY4) resulting in the high …

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, …

Effects Of Climate Change On The Potential Distribution Of 12 Endemic Lizards Of The Genus Plestiodon Of Mexico, Mayra Oyervides

Theses and Dissertations - UTB/UTPA

Anthropogenic global climate change is a large scale threat to biodiversity. Species distribution models (SDMs) were created to assess the possible effects of climate change on the distribution of 12 Plestiodon lizards of Mexico. Species presence data was obtained from online databases, literature, and field data. Occurrences were correlated with 19 climatic variables from www.worldclim.org to model species' current suitable habitat. These models were then projected to future (2050) conditions for which bioclimatic information was downloaded from the CCAFS website. Forecasts were made using 4 General Circulatory Models, 2 IPCC scenarios, and the software MaxEnt. Models were replicated 10 times …

Taxonomic And Seasonal Variation Among Extant Hyracoids Based On Dental Microwear Texture Analysis, Ann Marie Walcutt

Graduate Theses and Dissertations

A number of works have been published on habitats and diets of living hyraxes but much remains to be learned about the paleoenvironment contexts of the much larger, more dominant but now extinct forms of the order. Here, I analyze the dental microwear of modern hyraxes to assess dietary and ecological relationships among the four extant species of Procaviidae: Heterohyrax brucei, Procavia capensis, Dendrohyrax arboreus, and Dendrohyrax dorsalis. The purpose of this study was to establish an extant baseline series for the interpretation of microwear texture patterns, and inference of diets, of extinct members of the …

Snow Monkeys In South Texas, A Thirty Year Study Of Behavioral Adaptation, Lou E. Griffin

Theses and Dissertations - UTB/UTPA

A thirty year study of a transplanted species of primate, Macaca fuscata, Japanese snow monkey, documents the environmental influences on an intact troop relocated from Arashiyama, Japan to south Texas. These influences include novel disease, toxins, and predation. The effects of the environment on the social structure, hierarchy, and population of the primates are presented. The study begins in 1972 and is completed in 2002.