Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

PDF

Theses/Dissertations

Health and environmental sciences

Animal Sciences

Articles 1 - 21 of 21

Full-Text Articles in Life Sciences

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 ...


The Effects Of Dietary Probiotic Inclusion On Skeletal Health Of Poultry And Its Possible Mechanisms, Feifei Yan Dec 2016

The Effects Of Dietary Probiotic Inclusion On Skeletal Health Of Poultry And Its Possible Mechanisms, Feifei Yan

Open Access Dissertations

Probiotics are live microorganisms which may confer health benefits on the host when administered in appropriate amounts. Numerous studies have shown that probiotics improve bone health in humans and rodents with less information available on the skeletal health of avians given probiotics. The objective of this study was to determine the effects of probiotic supplementation on bone health of egg-laying and meat-type chickens. Dietary supplementation of a multi-species based probiotic reduced the percentage of shell-less eggs beginning at 4 wk following treatment and increased tibial and femoral bone mineral density in egg-laying hens at 7 wk post-treatment. Similarly, bone mineralization ...


Phenotypic Analysis And Localization Of Leukocytes At The Site Of Intradermal Injection Of Phytohemagglutinin In Chickens, Kallie Alyce Sullivan Dec 2016

Phenotypic Analysis And Localization Of Leukocytes At The Site Of Intradermal Injection Of Phytohemagglutinin In Chickens, Kallie Alyce Sullivan

Theses and Dissertations

Phytohemagglutinin (PHA) is commonly used to gain insight into an individual’s cellular immuno-competence. PHA is typically injected intradermally (i.d.) into the skin (e.g. wing web) and the tissue swelling response is then monitored, whereby the extent of the swelling positively relates to the individual’s cellular immune system capabilities. Although i.d. injected PHA was shown to stimulate mononuclear cell- and basophil-infiltration to the site of injection, reports on temporal, qualitative and quantitative aspects of the local PHA response are limited. The objective of this study was to use the growing feather (GF) as a cutaneous test-site ...


Effect Of Delayed Wrapping And Wrapping Source On Intake And Digestibility Of Alfalfa Silage In Gestating Sheep, Valens Niyigena Dec 2016

Effect Of Delayed Wrapping And Wrapping Source On Intake And Digestibility Of Alfalfa Silage In Gestating Sheep, Valens Niyigena

Theses and Dissertations

Baling silage with oxygen can result in dry matter deterioration and reduce silage intake by animals. This study was conducted to investigate the effects of two different wrapping sources and time intervals between baling and wrapping on intake and digestibility of alfalfa silage. The second objective was to assess the correlation of alfalfa silage fermentation parameters with intake and digestibility parameters in gestating sheep. Alfalfa silage was baled in large round bales then wrapped with plastic either with (KURA) or without (SUN) an oxygen-limiting barrier either the day of baling or 1, 2 or 3 d after baling. Beginning in ...


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 ...


Identification Of Biomarkers Associated With Rous Sarcoma Virus-Induced Tumors In Two Divergently Selected Chicken Lines, Ashley Hayden Aug 2016

Identification Of Biomarkers Associated With Rous Sarcoma Virus-Induced Tumors In Two Divergently Selected Chicken Lines, Ashley Hayden

Theses and Dissertations

Poultry has become especially important to genetic research due to breeding feasibility, short generation turnover, and ease of maintaining large populations. The discovery of virus induced cancer has paved the way for further genetic studies. Rous Sarcoma Virus (RSV) is a tumor-causing virus that infects poultry. While not prevalent today, it can serve as a model for virus-induced cancer in humans and create additional insight to marker assisted selection in poultry. Genetically selected Arkansas Progressor (AP) and Arkansas Regressor (AR) chicken lines have been established and maintained at the Arkansas Experimental Station (AES) in Fayetteville, AR. Previous research has investigated ...


Innate Immunity In Chickens: In Vivo Responses To Different Pathogen Associated Molecular Patterns, Kristen Alicia Byrne Aug 2016

Innate Immunity In Chickens: In Vivo Responses To Different Pathogen Associated Molecular Patterns, Kristen Alicia Byrne

Theses and Dissertations

Pattern recognition receptors (PRRs) on host cells recognize motifs known as pathogen associated molecular patterns (PAMPs) that are common to groups of microbes. Examples include LPS on Gram-negative bacteria, the structural motif PGN common to all bacteria, MDP the smallest immunostimulatory unit of PGN, and poly I:C the dsRNA analog. PAMP recognition by and stimulation of the innate immune system is crucial to an individual’s ability to quickly limit microbial growth and stimulate the adaptive immune system. Characterization of the in vivo immune responses initiated by PAMPs has not been directly addressed. Using growing feathers (GF) as a ...


Proteomic Characterization Of Eggshell Membranes And Their Effect On Poultry Physiology And Immunity, Sarbjeet Kaur Makkar May 2016

Proteomic Characterization Of Eggshell Membranes And Their Effect On Poultry Physiology And Immunity, Sarbjeet Kaur Makkar

Theses and Dissertations

The use of antibiotics in poultry growth and disease control has led to antibiotics resistant problem in human beings, which is a big concern among consumers. With the necessity for judicious use of antibiotics in poultry production, alternative strategies to improve disease resistance in poultry production are necessary. The research is more inclined towards using the natural products available to grow healthier and antibiotic free meat animals. In the context of exploring natural and sustainable resource of alternative to antibiotics, the biochemical milieu of eggshell membranes (ESM) were analyzed by using mass spectrometry techniques including matrix assisted laser desorption ionization ...


Evaluation Of The Impact Of Meat And Bone Meal Nutritional Variability On Broiler Performance, Christopher Caleb Eagleson Dec 2015

Evaluation Of The Impact Of Meat And Bone Meal Nutritional Variability On Broiler Performance, Christopher Caleb Eagleson

Theses and Dissertations

The objective of this trial was to determine if varying the nutritional composition of meat and bone meal (MBM) would impact broiler performance and yield compared to diets which provide a consistent quality of MBM. Twelve hundred day-old male broilers from the Cobb 500 female line were randomly allocated to 48 pens (25 chicks/pen; 22 square feet) and grown to 49 days of age. Starter, grower, and withdrawal diets were formulated to contain MBM at 10, 7.5 and 5% respectively using the Cobb nutritional standards. Four treatments provided were: 1) H.J. Baker proprietary blend, ProPlus 57 fed ...


The Effect Of Alternative Fertilization And Application Time On Voluntary Intake Of Forages, Jessica Clark Dec 2015

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

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 ...


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 Dec 2015

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

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 ...


Responses Of Two Strains Of Broilers To Diets Varying In Essential Amino Acid Density And Energy Levels, Tyler James Clark Dec 2015

Responses Of Two Strains Of Broilers To Diets Varying In Essential Amino Acid Density And Energy Levels, Tyler James Clark

Theses and Dissertations

The responses of two different commercial strains of broilers to diets varying in overall amino acid levels and metabolizable energy levels were observed. Amino acid levels used were 80%, 90%, 100%, 110%, 120%, and 130% of Ross recommended minimum digestable levels of essential amino acids. Energy levels used were either below or above Ross recommended metabolizable energy levels. Diets were fed for 56 days. The two strains were a fast growing broiler strain and a slower growing broiler strain. A selection of birds from each pen was processed at 35, 43, and 56 days of age. Average body weights, cumulative ...


Water Consumption Behavior In Broilers, David Harold Mccreery Jul 2015

Water Consumption Behavior In Broilers, David Harold Mccreery

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 ...


Novel Biomarkers For Calcium And Phosphorus Metabolism In Breeder Hens And Broilers, Andrew Dick Magnuson Jul 2015

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

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 ...


Evaluating Economic And Environmental Impacts Of Changing Herd Sire Genetics On Arkansas Cow-Calf Operations, Daniel Keeton Aug 2013

Evaluating Economic And Environmental Impacts Of Changing Herd Sire Genetics On Arkansas Cow-Calf Operations, Daniel Keeton

Theses and Dissertations

This research looks at impacts of changing sires, and thus bull genetics, on cow-calf operations of varying land and herd sizes in the state of Arkansas. A 2012 Across-Breed EPD table, adjusted to the Angus breed, was used to estimate breed sire effects on birth weight and weaning weight of the herd's offspring (Kuehn and Thallman 2012a). Together with modified animal performance, the use of 2012 and most recent five- and ten- year Arkansas state average prices, allowed the evaluation of changing herd sires by accounting for breed type and hide color differences in prices. Using a spreadsheet tool ...


Characterization Of Host Immune Responses To Eimeria Adenoeides Infection In Turkey Poults, Ujvala Deepthi Gadde Aug 2013

Characterization Of Host Immune Responses To Eimeria Adenoeides Infection In Turkey Poults, Ujvala Deepthi Gadde

Theses and Dissertations

Coccidiosis is a common enteric disease of turkeys that is caused by protozoan parasites belonging to the genus Eimeria. There are about seven species of Eimeria that affect turkeys and of these E. adenoeides is the most pathogenic and commonly recognized. Infection with Eimeria is known to induce a long lasting protective immunity in chickens, but nothing is known regarding the acquisition of immunity to Eimeria in turkeys. The experiments reported here were aimed at investigating the biological and cellular immune response to E. adenoeides in turkey poults under different conditions of exposure. In experiment 1 (Chapter II), 20 day ...


Effects Of Using Canola Meal As A Protein Source In Broiler Diets, Charles Danny Bradley Jr May 2013

Effects Of Using Canola Meal As A Protein Source In Broiler Diets, Charles Danny Bradley Jr

Theses and Dissertations

Six experiments were conducted to evaluate the response of broilers fed canola meal. Experiment 1 assessed performance and carcass yields when broilers were fed various combinations of canola and soybean meal in nutritionally balanced diets based on digestible amino acid values. The results suggested that canola meal can be used in isocaloric diets as a partial replacement for Soybean meal.

Experiment 2 assessed broiler performance and carcass yields when using various levels of canola meal in broiler diets with a constant level of supplemental poultry oil. The resulting data suggested when diets are formulated with a constant level of supplemental ...


Response Of Broiler Chickens To Variation In Dietary Nutrient Content, Sarah Diane Goodgame Dec 2012

Response Of Broiler Chickens To Variation In Dietary Nutrient Content, Sarah Diane Goodgame

Theses and Dissertations

Rising feed costs, environmental pollution concerns targeted at animal agriculture, a worldwide focus on sustainability and the never ending battle to improve production and efficiency within the poultry industry challenges nutritionists to focus on products to improve nutrient digestibility and decrease feed costs while at the same time maximizing performance. The research presented in this dissertation focuses on improving nutrient utilization of protein sources with protein liberating enzymes currently available commercially. The research also conducted addresses the addition of crystalline amino acids valine and isoleucine and their effect on improving efficiency of broilers.

The first research project compared the efficacy ...


A Role Of Environmental Components In Autoimmune Vitiligo Of Smyth Line Chickens, Lei Dong May 2012

A Role Of Environmental Components In Autoimmune Vitiligo Of Smyth Line Chickens, Lei Dong

Theses and Dissertations

The Smyth line (SL) of chickens is a well-established animal model for the study of spontaneous autoimmune vitiligo, displaying all the characteristics of human vitiligo. In humans, phenolic derivative 4-tertiary butyl phenol (4-TBP) has been shown to trigger vitiligo in susceptible individuals. In vitiligo-prone SL-chickens, live turkey herpesvirus (HVT) infection at hatch was identified as the most effective trigger of SL-vitiligo expression. This dissertation examined the role of the environmental factors 4-TBP and HVT in the etiology of SL-vitiligo. Specifically, the generation of reactive-oxygen-species by melanocyte-containing feather tissue (MC-FT) and cultured melanocytes in response to 4-TBP exposure in vitro (Study ...


Investigation Of A Locus On Chromosome 9 For Contributions To Pulmonary Hypertension Syndrome In Broilers, Sriram Krishnamoorthy May 2012

Investigation Of A Locus On Chromosome 9 For Contributions To Pulmonary Hypertension Syndrome In Broilers, Sriram Krishnamoorthy

Theses and Dissertations

Although the ascites syndrome in chickens has been investigated for years, it continues to inflict financial losses to the world poultry industry. It is estimated that 8% of the 361 million broiler deaths are due to ascites leading to losses of millions of dollars annually. Efforts to curb the incidence of ascites are typically designed to slow early growth. This limits the birds' ability to show its true genetic potential and impacts later yields. In 1994 lines divergent for susceptibility to ascites were established from a commercial sire line through sibling selection of birds reared at local altitude after testing ...


Intake, Digestibility, Insitu Disappearance And Ruminal Fermentation Of Bermuda Grass Hay By Lactating Beef Cows Offered Corn Or Hominy Feed As Supplements, Zibani Madzonga May 2012

Intake, Digestibility, Insitu Disappearance And Ruminal Fermentation Of Bermuda Grass Hay By Lactating Beef Cows Offered Corn Or Hominy Feed As Supplements, Zibani Madzonga

Theses and Dissertations

Hominy feed, a co-product of dry corn milling, has been evaluated to a limited extent in feedlot and dairy rations, but has not been evaluated as a supplemental energy source for lactating beef cows. The objective of this study was to determine the effect of level of hominy feed supplementation on intake, digestibility, in situ DM disappearance, and ruminal fermentation characteristics of medium quality bermudagrass hay. Five ruminally cannulated lactating beef cows (BW = 596 kg, SE = 13.9) were used in an experiment with a 5 × 5 Latin square design. Treatments were low hominy (LH; 0.25% of BW), medium ...