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Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson Dec 2023

Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson

Graduate Theses and Dissertations

Bats are an ecologically important taxon that can host zoonotic pathogens. Globally, many bat species are synanthropic and live closely with humans, often roosting in man-made structures. The spatial overlap between humans and bats creates opportunities for human-bat contact, which can lead to human exposure to bat-borne pathogens and conflicts that cause bat mortality. Despite this risk, little is known about the drivers and characteristics of these human-bat interactions in buildings and work is needed to understand this aspect of the wildlife-urban interface. In Chapter I, I present a literature review that identifies the geographic and taxonomic trends in reported …


Evaluation Of The Effect Of Enterococcus Cecorum Exposure During Late Embryogenesis On Systemic Disease And Early Performance In Broiler Chickens, Marcela Arango May 2023

Evaluation Of The Effect Of Enterococcus Cecorum Exposure During Late Embryogenesis On Systemic Disease And Early Performance In Broiler Chickens, Marcela Arango

Graduate Theses and Dissertations

The objective of this thesis was to investigate the effects of Enterococcus cecorum (EC) administration into the amnion at day 18 of embryogenesis on performance and septicemia development in broiler chickens. Chapter I consists of a brief overview of the thesis. Chapter II provides a literature review on EC-related disease in broiler chickens and methods to isolate, detect, and differentiate between commensal and pathogenic strains of EC. Chapter III consists of a study conducted to determine if different EC strains isolated from field cases that exhibited septicemia and high mortality impacted hatchability, livability, organ colonization, and early performance in broiler …


An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull May 2023

An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull

Graduate Theses and Dissertations

Orthohantaviruses are a global group of viruses found primarily in rodents, though several viruses have also been found in shrews and moles. Many rodent-borne orthohantaviruses are capable of causing one of several diseases in humans, and the mortality associated with these diseases ranges from < 0.1% - 50% depending on the specific etiological virus. In North and South America, orthohantavirus research was ignited by an outbreak of severe disease in the Four Corners region of the United States in 1993. However, despite the discovery of over 20 orthohantaviruses in the Americas, our understanding of orthohantavirus ecology and virus-host dynamics in this region is still limited, and orthohantavirus surveillance is generally restricted in scope to select regions and small portions of host distributional ranges. In Chapter I, I present a literature review on the current understanding of American rodent-borne orthohantavirus ecology. This review focused on under-studied orthohantaviruses, addressing gaps in knowledge by extrapolating information from well-studied orthohantaviruses, general rodent ecology, and occassionally from Eurasian orthohantavirus-host ecology. There were several key conclusions generated from this review that warrant further research: 1) the large number of putative orthohantaviruses and gaps in orthohantavirus evolution necessitate further surveillance and characterization, 2) orthohantavirus traits differ and are more generalizable based on host taxonomy rather than geography, and 3) orthohantavirus host species are disproportionately found in grasslands and disturbed habitats. In Chapter II, I present a prioritized list of rodent species to target for orthohantavirus surveillance based on predictive modeling using machine learning. Probable orthohantavirus hosts were predicted based on traits of known orthohantavirus hosts using two different types of evidence: RT-PCR and virus isolation. Predicted host distributions were also mapped to identify geographic hotspots to spatially guide future surveillance efforts. In Chapter III, I present a framework for understanding and predicting orthohantavirus traits based on reservoir host phylogeny, as opposed to the traditional geographic dichotomy used to group orthohantaviruses. This framework establishes three distinct orthohantavirus groups: murid-borne orthohantaviruses, arvicoline-borne orthohantaviruses, and non-arvicoline cricetid-borne orthohantaviruses, which differ in several key traits, including the human disease they cause, transmission routes, and virus-host fidelity. In Chapter IV, I compare rodent communities and orthohantavirus prevalence among grassland management regimes. Sites that were periodically burned had high rodent diversity and a high proportion of grassland species. However, rodent seroprevalence for orthohantavirus was also highest in burned sites, representing a trade-off in habitat management outcomes. The high seroprevalence in burned sites is likely due to the robust populations supported by the high quality habitat resulting from prescribed burning. In Chapters V and VI, I describe Ozark virus and Sager Creek virus, two novel orthohantaviruses discovered from specimens collected during Chapter IV. Both chapters report full genome sequences of the respective viruses and compare both nucleotide and protein phylogenies with related orthohantaviruses. Additionally in Chapter VI, I support the genetic analyses with molecular and ecological characterizations, including seasonal fluctuations in host abundance, correlates of prevalence, evidence of virus shedding, and information on host cell susceptibility to Sager Creek virus.


Isolation Of Drug-Sensitive Eimeria Species From Wild Turkey Feces And Development Of A Model Bioshuttle Program For Eimeria Meleagrimitis For Domestic Turkeys, Maria Carolina Trujillo Peralta Dec 2022

Isolation Of Drug-Sensitive Eimeria Species From Wild Turkey Feces And Development Of A Model Bioshuttle Program For Eimeria Meleagrimitis For Domestic Turkeys, Maria Carolina Trujillo Peralta

Graduate Theses and Dissertations

The objective of this thesis was to determine the anticoccidial profile of Eimeria spp. derived from wild turkeys. These drug-sensitive Eimeria spp. have potential to be used as vaccine candidates to control coccidiosis in commercial turkeys. Chapter two consists of a brief literature review focused on coccidiosis in turkeys. Chapter three addresses the methodologies utilized to isolate, recover, and speciate Eimeria recovered from wild turkey feces in the eastern two-thirds of the United States. From this, we successfully obtained single oocyst-derived stocks for E. meleagrimitis, E. dispersa, E. meleagridis, E. gallopavonis, and E. adenoeides. Chapter four describes the experiment conducted …


Optimization Of Clostridium Septicum Antigen Production And Evaluation Of Vaccine Administration Parameters For A Candidate Bacterin-Toxoid To Prevent Dermatitis In Commercial Turkeys, Aaron Forga Dec 2022

Optimization Of Clostridium Septicum Antigen Production And Evaluation Of Vaccine Administration Parameters For A Candidate Bacterin-Toxoid To Prevent Dermatitis In Commercial Turkeys, Aaron Forga

Graduate Theses and Dissertations

The objective of this thesis was to optimize the hemolytic activity of two isolates of Clostridium septicum to evaluate if hemolytic titer of C. septicum antigen at time of formalin inactivation corresponded to increased serum antibody titer to the C. septicum alpha-toxin of turkeys immunized with an experimental formalin inactivated bacterin-toxoid vaccine. Chapter 1 provides a brief overview of the thesis. Chapter 2 consists of a literature review focused on clostridial dermatitis, specifically C. septicum-associated dermatitis (cellulitis) that affects commercial turkeys. Chapter 3 outlines our attempts to optimize an experimental autogenous bacterin-toxoid vaccine as a potential strategy to mitigate clostridial …


Differential Impacts Of Hhv-6a Versus Hhv-6b Infection In Differentiated Human Neural Stem Cells, Elham Bahramian Dec 2022

Differential Impacts Of Hhv-6a Versus Hhv-6b Infection In Differentiated Human Neural Stem Cells, Elham Bahramian

Graduate Theses and Dissertations

Within the family Herpesviridae, sub-family β-herpesvirinae, and genus Roseolovirus, there areonly three human herpesviruses that have been described: HHV-6A, HHV-6B, and HHV-7. Initially, HHV-6A and HHV-6B were considered as two variants of the same virus (i.e., HHV6). Despite high overall genetic sequence identity (~90%), HHV-6A and HHV-6B are now recognized as two distinct viruses. Sequence divergence (e.g., >30%) in key coding regions and significant differences in physiological and biochemical profiles (e.g., use of different receptors for viral entry) underscores the conclusion that HHV-6A and HHV-6B are distinct viruses of the β-herpesvirinae. Despite these viruses being implicated as causative agents in …


Identification Of Possible Vectors For Histomoniasis In Turkeys On Commercial Farms In Arkansas And Oklahoma, Treva Dillon Dec 2022

Identification Of Possible Vectors For Histomoniasis In Turkeys On Commercial Farms In Arkansas And Oklahoma, Treva Dillon

Graduate Theses and Dissertations

Histomonas meleagridis, is a parasitic protozoan, commonly found in the gallinaceous species of birds and is the causative agent of Blackhead disease. The cecal worm, known as Heteraskis gallinarum, acts as a vector in the spread of H. meleagridis in gallinaceous birds. H. meleagridis develops inside the cecal worm and in its eggs which allows H. meleagridis a method to survive in the environment. Blackhead disease causes high mortality rates in both chickens and turkeys; however, turkeys are noted to have a higher mortality rate compared to chickens. Molecular diagnostic testing such as PCR has been developed by creating primers …


Intestinal Microbiota Analysis Of Broiler Chickens Under Necrotic Enteritis Challenge And Tributyrin Supplementation, Taylor Nicole Mckinney Aug 2022

Intestinal Microbiota Analysis Of Broiler Chickens Under Necrotic Enteritis Challenge And Tributyrin Supplementation, Taylor Nicole Mckinney

Graduate Theses and Dissertations

Poultry is a staple protein source for most of the planet. Until recently, antibiotic growth promoters (AGPs) were used to prevent illnesses in commercial chicken production. Currently, this is not possible due to regulations and consumer concern, but without such a preventative, diseases like necrotic enteritis (NE) have reemerged, posing a threat to bird health, and ultimately, our food source. Necrotic enteritis is a severe gastrointestinal disease caused by the gram-positive pathogen, Clostridium perfringens. Clinical features of this disease are diarrhea, intestinal lesions, and death, with a high transmission rate. In a subclinical form, growth performance is diminished and is …


Histomonosis In Turkeys – Factors Influencing Transmission, Pathogenesis, And The Search For Prophylactic Or Therapeutic Compounds, Thainá Landim De Barros Aug 2022

Histomonosis In Turkeys – Factors Influencing Transmission, Pathogenesis, And The Search For Prophylactic Or Therapeutic Compounds, Thainá Landim De Barros

Graduate Theses and Dissertations

The incidence of histomonosis has been increasing in poultry since the ban of prophylactic and therapeutic compounds. Histomonosis is caused by the protozoa Histomonas meleagridis. The objective of this dissertation was to investigate factors impacting the pathogenesis and transmission of histomonosis and to evaluate compounds that could potentially prevent or reduce the severity of histomonosis in turkeys. In the first study, the effect of sodium chlorate and sodium nitrate on reducing histomonads growth was tested in vitro and added to a basal turkey diet. A decrease in the growth of histomonads in vitro was observed, but no in vivo effect …


Investigating Molecular Mechanisms Behind Bacterial Chondronecrosis With Osteomyelitis (Bco) Pathogenesis In Modern Broilers, Alison Ramser May 2022

Investigating Molecular Mechanisms Behind Bacterial Chondronecrosis With Osteomyelitis (Bco) Pathogenesis In Modern Broilers, Alison Ramser

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis (BCO), a leading cause of lameness in broiler chickens, is characterized by infection, inflammation, and bone attrition. There are currently no effective treatments and positive diagnosis is only possible through necropsy evaluations. Lameness is also a rising animal welfare and economic concern, making prevention and detection of BCO all the more critical. These challenges are exacerbated by a lack of mechanistic understanding of BCO’s etiology. The question I asked during my dissertation was how bacteria induce bone attrition in BCO pathology. My research has shown that mitochondrial dysfunction is characteristic of BCO conditions along with autophagy …


Evaluation Of The Effect Of A Lippia Organoides Essential Oil Extract On Clostridium Perfringens Proliferation In Vitro And Necrotic Enteritis In Broiler Chickens, Makenly E. Coles May 2022

Evaluation Of The Effect Of A Lippia Organoides Essential Oil Extract On Clostridium Perfringens Proliferation In Vitro And Necrotic Enteritis In Broiler Chickens, Makenly E. Coles

Graduate Theses and Dissertations

The purpose of the present research was to assess the effects of essential oils derived from the plant Lippia organoides on performance parameters, intestinal integrity, and necrotic enteritis (NE) in broiler chickens. To do this, a previously established challenge model for NE was utilized which included challenging with Salmonella Typhimurium on day 0, Eimeria maxima on day 18, and Clostridium perfringens on days 22 and 23. Treatment groups included a 1) non-challenged, negative control, 2) challenged control, and 3) challenged, Lippia origanoides (37ppm in the diet). Group 1 (negative control) had significantly (P < 0.05) higher body weight gain from d8-25 and d0-25 compared to both challenged groups. Feed intake was significantly different for all three groups (P < 0.05) at 8-25 days and 0-25 days with group 1 having the highest feed intake for both time periods. Total mortality was greater in the positive control when compared to both the negative and treatment groups. NE lesion scores were significantly different between all groups with the positive control having the highest mean lesion scores and the negative control having a mean lesion score of 0. The positive control group had the highest FITC-d amounts detected in the sera, being statistically higher than both the treatment group and negative group which were both statistically different from each other. At the present inclusion rate for the essential oil (37 ppm), there was an overall reduction in the negative impact from the NE infection. Further studies should be conducted to reach more significant conclusions.


Investigation Of Histomoniasis Prevention In Poultry, Lesleigh Beer Dec 2021

Investigation Of Histomoniasis Prevention In Poultry, Lesleigh Beer

Graduate Theses and Dissertations

Histomonas meleagridis is the etiological agent of histomoniasis, also commonly known as blackhead disease. This protozoal disease of poultry is detrimental to turkeys with flock mortalities often reaching 80-100%, although other gallinaceous birds are susceptible. Since the voluntary removal of nitarsone in 2015, the poultry industry is suffering with no approved prophylactics, therapeutics, or vaccines for this disease. The objectives of this dissertation were to evaluate multiple methods for prevention or control of histomoniasis, including dietary chemoprophylaxis and vaccination. Specifically, this research evaluated quinine as a chemoprophylactic candidate (Chapter 3) or live-attenuated H. meleagridis as vaccine candidates (Chapter 4) in …


Evaluation Of Two Neonatal Challenge Models For Broiler Chickens And Their Effects On Early Performance Parameters, Callie Selby Dec 2021

Evaluation Of Two Neonatal Challenge Models For Broiler Chickens And Their Effects On Early Performance Parameters, Callie Selby

Graduate Theses and Dissertations

Formaldehyde fumigation in poultry hatch cabinets has been utilized for sanitation of hatching eggs for over a century. Formaldehyde is utilized to minimize pathogenic microbes on the surface of the egg as well as the microbial bloom during the hatching process. While formaldehyde is effective, its use is regulated in the United States and Europe due to its carcinogenic nature. Formaldehyde has been shown to damage the cuticle of the egg, cause embryonic death, and damage the epithelial lining of the respiratory tract of freshly hatched chicks, predisposing them for respiratory infection. Alternatives for formaldehyde fumigation must be identified and …


Nanomaterial-Based Biosensors For Detection Of Salmonella Typhimurium And Avian Influenza Virus H5n1 In Poultry, Xinge Xi Jul 2021

Nanomaterial-Based Biosensors For Detection Of Salmonella Typhimurium And Avian Influenza Virus H5n1 In Poultry, Xinge Xi

Graduate Theses and Dissertations

This research focused on developing biosensing method and biosensing device for rapid detection of pathogens in poultry: Salmonella Typhimurium and avian influenza virus H5N1. The first part of the dissertation reports an original research on the development of a portable biosensing device for Salmonella detection. The device was designed and constructed based on a previously developed optical biosensing method, using immuno-magnetic nanoparticles to specifically capture target bacteria, and immuno-quantum dot beads to label the target bacteria for fluorescence detection. All the actions of sample mixing, magnetic separation, and fluorescence detection were controlled automatically in a disposable microfluidic chip in the …


Directed Genome Evolution To Identify Genes For Macrophage Survival By Staphylococcus Agnetis, Sonali Lakshika Anne Lenaduwe Lokuge Jul 2021

Directed Genome Evolution To Identify Genes For Macrophage Survival By Staphylococcus Agnetis, Sonali Lakshika Anne Lenaduwe Lokuge

Graduate Theses and Dissertations

Bacterial Chondronecrosis with Osteomyelitis (BCO) is a debilitating infection that negatively impacts animal welfare and costs the broiler industry billions of dollars annually. We have previously isolated Staphylococcus agnetis 908 from BCO samples obtained from broilers at the University of Arkansas research farm. This isolate can induce BCO lameness at greater than 50% in broilers exposed to the pathogen in drinking water. We found that S. agnetis 908 is capable of surviving and escaping macrophages compared to a closely related cattle isolate,1379. Through Directed Genome Evolution (DGE) we identified that this difference is at least partially associated with an alanine …


Survey Of Ticks And Tick-Borne Pathogens Associated With Feral Swine (Sus Scrofa) In Arkansas, Haylee Campbell May 2021

Survey Of Ticks And Tick-Borne Pathogens Associated With Feral Swine (Sus Scrofa) In Arkansas, Haylee Campbell

Graduate Theses and Dissertations

Feral hogs (Sus scrofa L.) are an invasive species throughout the southeast United States and found in every Arkansas county. As feral hogs invade new habitat, they can disrupt ecosystems, damage agriculture systems, and bring ticks and tick-borne pathogens with them. There are no surveys of the tick species parasitizing the Arkansas feral hog populations or the pathogens they carry. This is a public health concern because feral hogs occupy often same geographical regions as humans and livestock and can harbor over 45 animal diseases and parasites. The ticks carried by feral hogs can carry tick-borne pathogens that can cause …


Development Of Aptamer Rolling Circle Amplification Platform As A Vaccine Adjuvant To Control Salmonella In Broiler Chickens, Abigeal Iyabode Omolewu Jan 2021

Development Of Aptamer Rolling Circle Amplification Platform As A Vaccine Adjuvant To Control Salmonella In Broiler Chickens, Abigeal Iyabode Omolewu

Graduate Theses and Dissertations

Salmonella has been a major source of concern in public health and food industry. It is the cause of gastrointestinal illness and fever called salmonellosis. Severe cases of salmonellosis have resulted in hospitalization and even death around the world. Salmonella can be found in the intestinal tract of animals including chickens and can be transmitted to human through contaminated food. Hence, it is highly important to find ways of reducing the transmission of Salmonella from chickens to humans. This work is focused on the control of Salmonella in broiler chicken through the development of novel vaccine adjuvant. Two different aptamer …


Biogeography Of The Bovine Respiratory Microbiome And Its Relationship With Bovine Respiratory Disease, Jianmin Chai Dec 2020

Biogeography Of The Bovine Respiratory Microbiome And Its Relationship With Bovine Respiratory Disease, Jianmin Chai

Graduate Theses and Dissertations

Bovine respiratory disease (BRD) is the most common and costly disease in the beef cattle industry, leading to high morbidity, mortality and huge economic loss. Despite the recent advances in vaccination and antimicrobial techniques, no significant health-improved outcomes have developed. Due to a deep investigation of the microbiome, respiratory microbiotas are known to have important roles for host health and disease. However, BRD specific pathogens have not yet been identified since they are found in both healthy and diseased animals. A systemic and comprehensive study of the biogeography of the bovine respiratory microbiome and its relationship with BRD is lacking …


Examining Pathogenesis And Preventatives In Spontaneous And Staphylococcus-Induced Bacterial Chondronecrosis With Osteomyelitis In Broilers, Nnamdi Simon Ekesi Dec 2020

Examining Pathogenesis And Preventatives In Spontaneous And Staphylococcus-Induced Bacterial Chondronecrosis With Osteomyelitis In Broilers, Nnamdi Simon Ekesi

Graduate Theses and Dissertations

Bacterial chondronecrosis with osteomyelitis is the most important cause of lameness in broilers. This is important to poultry production, as it poses animal welfare issues, and causes a significant loss in revenue. The remediation of this disease requires the study of its etiology with fitting models and evaluating preventatives. The research reported herein covers genomic virulence analysis of BCO isolates, mainly Staphylococcus aureus, and Escherichia coli retrieved from lame birds. We found that S. aureus isolates were closest to chicken strains in Europe but may have been in the Arkansas area for a decade. Phylogenomics suggest our S. aureus is …


Fate And Dissemination Of Salmonella Reading In Market-Age Turkeys At Processing Using Oral Gavage Challenge Model, Aaron Ashcraft Dec 2020

Fate And Dissemination Of Salmonella Reading In Market-Age Turkeys At Processing Using Oral Gavage Challenge Model, Aaron Ashcraft

Graduate Theses and Dissertations

This study aimed to evaluate the fate and dissemination of Salmonella Reading (SR) in market-age turkeys using an oral gavage challenge model. One hundred twenty-eight-week-old commercial turkey hens were moved from commercial production to research facilities. Upon arrival, a combination of enrofloxacin, 10 mg/kg, and florfenicol, 20 mg/kg, were orally administered sequentially before comingled placement on fresh pine shavings. Turkeys were challenged with 108 cfu SR by oral gavage on days 4 and 7 post-placement. Subsets were subjected to simulated commercial processing on days 14 (n=40), 21 (n=40) and 28 (n=32) post-placement (corresponding to 10, 11, and 12 weeks of …


Mitochondrial Contributions To Disuse Atrophy: Let’S Talk About Sex, Megan Rosa-Caldwell Jul 2020

Mitochondrial Contributions To Disuse Atrophy: Let’S Talk About Sex, Megan Rosa-Caldwell

Graduate Theses and Dissertations

Skeletal muscle atrophy is a hallmark of many pathologies and is associated with disease prognosis, quality of life, and mortality. Specifically, lack of contractile activity of the muscle can result in disuse-associated atrophy. Disuse-induced atrophy is a common phenomenon in intensive care unit (ICU) patients and significantly impacts patient prognosis and ability to transition of out of intensive care. However, effective therapeutics to mitigate disuse-associated atrophy do not exist, clearly demonstrating the scientific and clinical need to further understand mechanisms contributing to disuse atrophy. In particular, a significant portion of the scientific literature has utilized male models, yet there is …


Hpv Vaccination In Females: The Role Of Primary Health Care And Primary Health Care Providers, Brooke Bouza Jul 2020

Hpv Vaccination In Females: The Role Of Primary Health Care And Primary Health Care Providers, Brooke Bouza

Graduate Theses and Dissertations

Two reasons for subpar coverage of the Human papillomavirus (HPV) vaccine are missed clinical opportunities and nonacceptance of the vaccine upon recommendation from a medical provider. The purpose of study one was to examine factors associated with access and adherence to physician’s recommendations in association with HPV vaccine uptake. Data were obtained from National Health Interview Survey (2017). Variables theoretically related to clinical opportunities and adherence to physician’s recommendations were examined in association with HPV vaccine uptake. Univariate logistic regressions were run to determine the associations between the aforementioned variables and uptake of the HPV vaccine. Multinomial logistic regressions were …


Food Safety Risk In An Indoor Microgreen Cultivation System, Gina Marie Misra May 2020

Food Safety Risk In An Indoor Microgreen Cultivation System, Gina Marie Misra

Graduate Theses and Dissertations

Microgreens are immature sprouts of edible plants, sharing some similarities with sprouted seeds and petite leafy greens. Since they are most often grown in containers in buildings or greenhouses, they present a new area for food safety research at the intersection of the built environment and produce farming. Contamination by human pathogens has been extensively studied in other types of produce typically eaten raw, including sprouted seeds, which have been implicated in numerous outbreaks of salmonellosis over the last several decades. There is a paucity of knowledge about the microgreen sector of the fresh-cut industry; thus, it was determined that …


Evaluation Of Anthelmintic Therapies In A Fall Calving Beef Cowherd, Laine Zammit May 2020

Evaluation Of Anthelmintic Therapies In A Fall Calving Beef Cowherd, Laine Zammit

Graduate Theses and Dissertations

Internal parasitism inevitability prompts economic loss in beef cattle production by decreasing growth performance and reproductive traits. Today, the most widely used class of anthelmintic used to treat parasitism, is the macrocyclic lactone. Many studies have conflicting results on the efficacy of macrocyclic lactones (ML) efficacy against internal parasitism. The objective of this study was to evaluate the effectiveness of moxidectin and eprinomectin, two of the MLs, on cow performance. Multiparous fall calving, crossbred beef cows (n = 106) were allocated randomly to 1 of 3 anthelmintic treatments: 1) Negative control (CON), in which cows did not receive an anthelmintic, …


The Acute Effect Of Water Intake On Glucose Regulation In Low Drinkers, Adam David Seal Dec 2019

The Acute Effect Of Water Intake On Glucose Regulation In Low Drinkers, Adam David Seal

Graduate Theses and Dissertations

Previous evidence suggests the hormone arginine vasopressin (AVP) may be a modifiable factor contributing to hyperglycemia. Significant differences in urine concentration and copeptin, a marker for AVP, have been observed between low and high water drinkers. Purpose: The purpose was to investigate the acute effect of adequate water intake on glucose regulation in low drinkers. Methods: 7 healthy (5 males, 2 female) low drinkers were recruited using a water frequency questionnaire (WFQ), spot and 24-h urine sample (age 43±6 y, BMI 30.9±3, WFQ volume 823±403 mL∙d-1, 24 h Uosm 961±105 mmol∙kg-1, copeptin 8.17±3.05 pmol∙L-1). During two experimental protocols, participants remained …


Methods To Evaluate Ruminant Animal Production Responses, Jose Manuel Diaz Gomez Dec 2019

Methods To Evaluate Ruminant Animal Production Responses, Jose Manuel Diaz Gomez

Graduate Theses and Dissertations

In experiment 1, 80 steers (197.0 kg initial body weight; BW for fall, 116.9 kg for spring), were stocked at 2.45 and 4.1 calves/ha in fall and spring, respectively in 16 tall fescue pastures [fall ergovaline (EV) = 1,475 ppb and spring EV = 1,173 ppb] under 2 treatments, mineral (MIN) (n = 8) and cumulative management (CM) (n = 8). Forage allowance did not differ (P = 0.76) between CM and MIN during fall but differed during spring (P ≤ 0.05, 2.55 vs. 3.22 kg DM/kg BW, for MIN and CM, respectively). For fall, average daily gain (ADG) resulted …


Estimation Of Genetic Components Related To Infectious Bovine Keratoconjunctivitis Susceptibility In Angus And Angus Derived Cattle Produced In The Southern United States, Eric Oxford Dec 2019

Estimation Of Genetic Components Related To Infectious Bovine Keratoconjunctivitis Susceptibility In Angus And Angus Derived Cattle Produced In The Southern United States, Eric Oxford

Graduate Theses and Dissertations

The economic impact of infectious bovine keratoconjunctivitis (IBK) has been documented in many parts of the world. Many researchers have observed that prevention of this disease is very difficult given current methodologies. This is primarily due to the multifactorial nature of this disease. The objective of this dissertation was to determine the impact of IBK on calf performance and estimate genetic parameters, heritability and estimated breeding values for IBK susceptibility. Data were analyzed using PROC GLIMMIX of SAS; while genetic parameters were estimated using a linear animal model for both single- and two-traits through MTDFREML. Additional evaluations calculated heritability using …


Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell Dec 2019

Quantitative Study Of The Antimicrobial Effects Of Silver On The Motility Of Escherichia Coli, Benjamin Russell

Graduate Theses and Dissertations

In recent decades, the number of antibiotic-resistant bacterial infections has grown to become a serious global threat. This rise can be attributed to the widespread misuse of antibiotics and the lack of newly developed drugs to fight resistant organisms. Novel bactericidal substances have, therefore, garnered significant research interest. Silver, due to its powerful antimicrobial effects, is one such substance. Silver is typically most effective in cationic form; however, advancements in nanotechnology have paved the way for the controlled fabrication of nano-silver. Silver nanoparticles have been shown to have increased antibacterial potency for a variety of reasons, including the release of …


Investigation Of Microbiota In Health And Disease Of Poultry, Bishnu Adhikari Aug 2019

Investigation Of Microbiota In Health And Disease Of Poultry, Bishnu Adhikari

Graduate Theses and Dissertations

The microbiotas play vital roles in health and diseases of both humans and animals. 16S rRNA genes sequence analysis is one of the most popular and commonly used methods in the analysis of microbiotas associated with hosts. In this dissertation, the microbiotas of chickens (broilers, breeders, and layers) and turkeys were evaluated by 16S rRNA gene sequencing. Characterization of the culturable subpopulations of Lactobacillus in the chicken gut can serve as a valuable resource for probiotic development. In Chapter 2, Lactobacillus subpopulations recovered on MRS from chicken gut were defined comprehensively for the first time using 16S rRNA gene profiling, …


Potential Antimicrobials For Controlling Listeria Monocytogenes In Frankfurters, Aaron Rashad Bodie Aug 2019

Potential Antimicrobials For Controlling Listeria Monocytogenes In Frankfurters, Aaron Rashad Bodie

Graduate Theses and Dissertations

Listeria monocytogenes is a pathogenic microorganism that causes Listeriosis. Listeriosis is a highly mortal disease with approximately 20% mortality rate. Listeria is psychrophilic, therefore it is able to survive in the refrigerator. This affects foods at cool storage such as fresh produce and RTE meats. To ensure the safety of RTE meat, post processing treatments are used such as vacuum packing, edible films, dip and treatment. One-way RTE can be treated is with the use of antimicrobials. However, in the past chemical substances were used. Currently, consumers want more natural and organic preservatives to combat health problems from toxic components …