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Discovery And Sequencing Of Novel And Identified Mosquito-Associated Viruses And Genetic Determinants Of Flavivirus Host Specificity, Jermilia Charles Jan 2019

Discovery And Sequencing Of Novel And Identified Mosquito-Associated Viruses And Genetic Determinants Of Flavivirus Host Specificity, Jermilia Charles

Graduate Theses and Dissertations

The advent of globalization and the continuing effects of climate change have exposed an even greater percentage of the world to disease agents carried by vectors which were once thought to be restricted to tropical or subtropical areas. Arthropods vectors such as mosquitoes and ticks harbor a number of emerging and re-emerging pathogens of public and veterinary health importance worldwide. These pathogens include viruses from four major families including the Flaviviridae, Bunyaviridae, Togaviridae and Reoviridae families. The Flavivirus genus is one of four genera in the Flaviviridae family, with over 70 species, the great majority of which are maintained in ...


Insights Into Early Earth Ocean Biogeochemistry From Intensive Monitoring Of Two Ferruginous Meromictic Lakes, Nicholas Lambrecht Jan 2019

Insights Into Early Earth Ocean Biogeochemistry From Intensive Monitoring Of Two Ferruginous Meromictic Lakes, Nicholas Lambrecht

Graduate Theses and Dissertations

Background. Life on early Earth was microbial and confined to iron-rich oceans, yet heavily influenced the world around it. Primary producers fixed carbon through anoxygenic photosynthesis. Other microbes produced gases, such as methane, which modulated Precambrian climate. All these biological processes still occur today, but in niche environments that are reminiscent of conditions on Earth billions of years ago.

Aims. The aims of this dissertation were to investigate microbes that influence iron and carbon cycling under ferruginous conditions. Specifically: (1) to characterize two lakes as geochemical analogs for early Earth oceans; (2) to explore factors that impact methane production, oxidation ...


A Comparison Of Brachyspira Hampsonii Isolates And The Evaluation Of Proteinase K Vaccine Preparations In Swine, Christine Muehlenthaler Jan 2019

A Comparison Of Brachyspira Hampsonii Isolates And The Evaluation Of Proteinase K Vaccine Preparations In Swine, Christine Muehlenthaler

Graduate Theses and Dissertations

Brachyspira hampsonii has been an emerging cause of swine dysentery (SD) since the mid to late 2000’s. Before the isolation of B. hampsonii, Brachyspira hyodysenteriae was the thought to be the sole etiologic agent of swine dysentery and the primary cause of mucohemmorhagic diarrhea in pigs (MHD). Research has been performed examining both whole cell and engineered B. hyodysenteriae vaccines, but little to no research has been reported for B. hampsonii. Quantification of Brachyspira cultures has been determined by CFUs, PCR, and whole cell counts; however, these methods have not previously been compared within the same study. Limitations with ...


Investigation Of Pathogenicity, Competitive Fitness, And Novel Methods For Rapid Diagnosis Of Salmonella 4,[5],12:I:- In Swine, Samantha Ann Naberhaus Jan 2019

Investigation Of Pathogenicity, Competitive Fitness, And Novel Methods For Rapid Diagnosis Of Salmonella 4,[5],12:I:- In Swine, Samantha Ann Naberhaus

Graduate Theses and Dissertations

Salmonella enterica subsp. enterica serovar 4,[5],12:i:- is widely accepted to be a monophasic variant of Salmonella Typhimurium. Salmonella 4,[5],12:i:- has been increasing significantly in prevalence worldwide over the past decade while S. Typhimurium has been subsequently decreasing. Both Salmonella serovars 4,[5],12:i:- and Typhimurium are contained in Salmonella serogroup B, which is currently the predominant serogroup in swine in the United States. However, this serogroup contains serovars of a wide range of pathogenic potential, with Typhimurium generally being associated with enterocolitis and Agona and Derby generally being considered to be of lesser ...


Microbial Associations Of Four Species Of Algal Symbiont-Bearing Foraminifera From The Florida Reef Tract, Usa, Makenna May Martin Jun 2018

Microbial Associations Of Four Species Of Algal Symbiont-Bearing Foraminifera From The Florida Reef Tract, Usa, Makenna May Martin

Graduate Theses and Dissertations

Marine microbiome research is a rapidly expanding field of study, as scientists investigate the functions of microbial associations in eukaryotic organisms. Foraminifera are among the most abundant shelled organisms in the oceans, yet little is known of their associated microbiomes. This study investigated microbes associated with four species of Foraminifera that host three kinds of algal endosymbionts. The Order Miliolida, Family Soritidae, was represented by three species: Archaias angulatus and Cyclorbiculina compressa, which both host chlorophyte symbionts, and Sorites orbiculus, which hosts dinoflagellate symbionts. The fourth species, Amphistegina gibbosa, belongs to the Order Rotaliida and hosts diatom endosymbionts. Bacterial DNA ...


Development Of A Novel Anti-Infectivity Platform For The Treatment Of Neglected Tropical And Infectious Diseases, Andrea Marie Binnebose Jan 2018

Development Of A Novel Anti-Infectivity Platform For The Treatment Of Neglected Tropical And Infectious Diseases, Andrea Marie Binnebose

Graduate Theses and Dissertations

This dissertation focuses on the design of novel strategies for the prevention and treatment of neglected tropical and infectious diseases using polyanhydride nanoparticles as a drug delivery platform. The overall goal of this research is to design efficacious drug delivery vehicles that are effective against the filarial nematode Brugia malayi and B. pahangi and intracellular bacteria Mycobacterium tuberculosis, M. paratuberculosis, and M. marinum. The primary goal is to use the polyanhydride nanoparticles to deliver high enough microenvironmental concentrations to cause the death of the organism, thereby reducing the mortality, morbidity, and transmission of the disease. While a wide array of ...


Biosurveillance Utilizing Engorged Ticks As Phlebotomists For Xenodiagnosis, Charles Elliott Lewis Jan 2018

Biosurveillance Utilizing Engorged Ticks As Phlebotomists For Xenodiagnosis, Charles Elliott Lewis

Graduate Theses and Dissertations

Emerging infectious diseases pose a global threat to both human and animal health. The majority of novel zoonotic pathogens occur along the interface between humans, domestic animals, and wildlife creating complex ecological interactions that can be intricate and difficult to decipher. The availability of a diverse array of methods and techniques of sampling and diagnosing these diseases expands the effectiveness of the surveillance programs needed to enact countermeasures to counteract their effects. The purpose of the research reported here is to investigate the use of ticks as biological samplers for the purpose of antibody-based xenosurveillance. We show that antibody diagnostic ...


Inactivation Of Enteric Pathogens And Natural Microflora In Pineapple Juice With Added Isoeugenol And Yucca Extract, Emalie Rhonda Hyacinth Thomas-Popo Jan 2018

Inactivation Of Enteric Pathogens And Natural Microflora In Pineapple Juice With Added Isoeugenol And Yucca Extract, Emalie Rhonda Hyacinth Thomas-Popo

Graduate Theses and Dissertations

Studies were conducted to determine the effectiveness of isoeugenol (ISO-EU) at 0 (control) and 0.50, 0.75, 1.0 and 1.5 μL mL-1 for inactivating three enteric pathogens (Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella enterica) and indigenous spoilage microflora in Tyndallized and raw pineapple juice (PJ) respectively, during refrigerated (4 ᵒC) storage of the juice. Sub-lethal injury of pathogen survivors in PJ and the effect of ISO-EU on sensory characteristics of PJ were also evaluated. Batches of Tyndallized PJ with added ISO-EU and YEX (0.5% w/v) were each inoculated with a five-strain mixture of ...


The Effect Of Manure Application Timing On The Persistence Of Phenotypic And Genotypic Antibiotic Resistance In Tile-Drained Hapludolls, Elliot George Rossow Jan 2018

The Effect Of Manure Application Timing On The Persistence Of Phenotypic And Genotypic Antibiotic Resistance In Tile-Drained Hapludolls, Elliot George Rossow

Graduate Theses and Dissertations

The application of swine manure to agricultural fields increases the abundance of antibiotic resistance genes (ARG) and antibiotic resistant bacteria (ARB) in soils. While manure-associated antibiotic resistant bacteria persist following application, there is potential for their transport through tile drainage. The environmental survival of bacteria in soil has been related to moisture and temperature, therefore differences in these environmental conditions between spring and fall soils may cause manure associated antibiotic resistance to behave differently following application. This encouraged exploring differences in the persistence of antibiotic resistant bacteria and antibiotic resistance genes in soil when manure is applied at different times ...


Development Of A Phage Display Library For Discovery Of Antigenic Brucella Peptides, Jeffrey Williams Jan 2018

Development Of A Phage Display Library For Discovery Of Antigenic Brucella Peptides, Jeffrey Williams

Graduate Theses and Dissertations

Current serological diagnostics of the zoonotic disease brucellosis, caused by the intracellular, facultative bacterial pathogen Brucella, is primarily limited to humoral antibodies against the O-side chain of the lipopolysaccharide. This limitation can result in false positives due to cross reactivity with other gram negative bacteria. Previous attempts to identify other molecular markers for diagnostic purposed haven’t resulted in sensitive and specific antigens. In the current study, we employed a new method for discovering novel Brucella proteins that induce humoral responses in cattle. We developed a phage display library that expresses 56 amino acid long Brucella peptides. Screening the library ...


Comparison And Evaluation Of Two Rapid Diagnostic Assays For The Identification Of Mycoplasma Species, Aric James Mcdaniel Jan 2018

Comparison And Evaluation Of Two Rapid Diagnostic Assays For The Identification Of Mycoplasma Species, Aric James Mcdaniel

Graduate Theses and Dissertations

Members of the class Mollicutes are unique among bacteria in that they are unable to synthesize a cell wall. These organisms are also difficult to culture and very slow-growing with some species requiring up to 40 days to culture. Many of these bacteria are also significant pathogens in humans and animals, so rapid identification of isolates is a necessary diagnostic step. Many different tests are used for identification of pathogenic Mollicutes (primarily Mycoplasma and Ureaplasma species), however most tests are not cost or time efficient. Two relatively recent diagnostic tools are matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and ...


Interactions Of Mycoplasma Hyopneumoniae With Extracellular Traps, Clair Mitzelfeldt Jan 2018

Interactions Of Mycoplasma Hyopneumoniae With Extracellular Traps, Clair Mitzelfeldt

Graduate Theses and Dissertations

Mycoplasma hyopneumoniae is the causative agent of enzootic pneumonia in swine. Infection with M. hyopneumoniae results in a mild, chronic disease and is further complicated by the establishment of other secondary infections. M. hyopneumoniae has finite biosynthetic capabilities, including a deficit in de novo nucleotide synthesis. Recent research has demonstrated that neutrophils can produce extracellular traps (ETs), chromatin nets decorated with granular proteins released into the extracellular environment for the purpose of interacting and sequentially eliminating pathogens. We hypothesized that M. hyopneumoniae was able to utilize a membrane nuclease to obtain nucleotides from extracellular traps to synthesize its own DNA ...


Evaluation Of A Microsphere-Based Immunoassay (Mia) In Measuring Diagnostic And Prognostic Markers Of Dengue Virus Infection, Jason H. Ambrose Nov 2017

Evaluation Of A Microsphere-Based Immunoassay (Mia) In Measuring Diagnostic And Prognostic Markers Of Dengue Virus Infection, Jason H. Ambrose

Graduate Theses and Dissertations

Infections with dengue viruses (DENV) constitute both a global problem as well as locally in Florida. DENV comprise four distinct serotypes of single-stranded RNA viruses and belong to the family Flaviviridae. DENV are among the most medically important arboviruses in the world and cases may currently exceed 400 million per annum. Additionally, dengue established its first recorded endemic transmission cycle in the state of Florida in over a half century, first within the Florida Keys during 2009-10 followed by an unrelated outbreak in Martin County in 2013. The clinical profile of DENV infections ranges from a mild febrile illness to ...


The Ecology Of Antibiotic Resistance: Sources And Persistence Of Vancomycin-Resistant Enterococci And Antibiotic Resistant Genes In Aquatic Environments, Suzanne M. Young Nov 2017

The Ecology Of Antibiotic Resistance: Sources And Persistence Of Vancomycin-Resistant Enterococci And Antibiotic Resistant Genes In Aquatic Environments, Suzanne M. Young

Graduate Theses and Dissertations

The growing crisis of antibiotic resistance is a major threat to ecosystems and human health. Infections caused by known and emerging antibiotic resistant pathogens are on the rise globally, with approximately 700,000 deaths per year caused by antibiotic resistant bacteria (1). In the United States, infections from antibiotic resistant bacteria cause more than 2 million illnesses and 23,000 deaths (2). Antibiotic resistant bacteria and antibiotic resistance genes are released into aquatic ecosystems through hospital waste, residential sewer lines and animal agricultural waste streams. Animal agriculture accounts for approximately 70% of antibiotic use in the United States (3). In ...


Mechanism Elucidation And Inhibitor Discovery Against Serine And Metallo-Beta-Lactamases Involved In Bacterial Antibiotic Resistance, Orville A. Pemberton Nov 2017

Mechanism Elucidation And Inhibitor Discovery Against Serine And Metallo-Beta-Lactamases Involved In Bacterial Antibiotic Resistance, Orville A. Pemberton

Graduate Theses and Dissertations

The emergence and proliferation of Gram-negative bacteria expressing β-lactamases is a significant threat to human health. β-Lactamases are enzymes that degrade the β-lactam antibiotics (e.g., penicillins, cephalosporins, monobactams, and carbapenems) that we use to treat a diverse range of bacterial infections. Specifically, β-lactamases catalyze a hydrolysis reaction where the β-lactam ring common to all β-lactam antibiotics and responsible for their antibacterial activity, is opened, leaving an inactive drug. There are two groups of β-lactamases: serine enzymes that use an active site serine residue for β-lactam hydrolysis and metalloenzymes that use either one or two zinc ions for catalysis. Serine ...


Packaging Of Genetic Material By Gene Transfer Agents (Gtas) Produced By Marine Roseobacter Species And Their Effect On Stimulating Bacterial Growth, Shahd Bader Aljandal Nov 2017

Packaging Of Genetic Material By Gene Transfer Agents (Gtas) Produced By Marine Roseobacter Species And Their Effect On Stimulating Bacterial Growth, Shahd Bader Aljandal

Graduate Theses and Dissertations

Horizontal gene transfer is one of the most important mechanisms for prokaryotic genome innovation and evolution. Gene Transfer Agents (GTAs) are phage-like particles that package small fragments of the genome of a GTA-producing bacterial cell. GTA chromosomal gene clusters usually contain 15-conserved open reading frames (ORFs) and are present in most of the sequenced marine alpha-proteobacteria genomes. Some marine strains have been shown to produce GTA particles that were biologically active in marine environment.

GTA particles range in size, morphology and the amount of host DNA they package. To date, the characteristics of GTAs are largely based on observations of ...


Cell Division Regulation In Staphylococcus Aureus, Catherine M. Spanoudis Oct 2017

Cell Division Regulation In Staphylococcus Aureus, Catherine M. Spanoudis

Graduate Theses and Dissertations

Cell division is a fundamental biological process that occurs in all kingdoms of life. Our understanding of cell division in bacteria stems from studies in the rod-shaped model organisms: Gram-negative Escherichia coli and Gram-positive Bacillus subtilis. The molecular underpinnings of cell division regulation in non-rod-shaped bacteria remain to be studied in detail. Rod-shaped bacteria possess many positive and negative regulatory proteins that are essential to the proper placement of the division septa and ultimately the production of two identical daughter cells, many of which are absent in cocci. Given that essential cell division proteins are attractive antibacterial drug targets, it ...


Role Of Viruses Within Metaorganisms: Ciona Intestinalis As A Model System, Brittany A. Leigh Sep 2017

Role Of Viruses Within Metaorganisms: Ciona Intestinalis As A Model System, Brittany A. Leigh

Graduate Theses and Dissertations

Marine animals live and thrive in a literal sea of microorganisms, yet are often able to maintain specific associations that are largely dictated by the environment, host immunity and microbial interactions. Animal-associated microbiomes include bacteria and viruses that vastly outnumber host cells, especially in the gut environment, and are considered to be integral parts of healthy, functioning animals that act as a metaorganism. However, the processes underlying the initial establishment of these microbial communities are not very well understood. This dissertation focuses on the establishment of a well-known developmental animal model, Ciona intestinalis (sea squirt), to study the establishment and ...


Discovering Antibacterial And Anti-Resistance Agents Targeting Multi-Drug Resistant Eskape Pathogens, Renee Fleeman Jul 2017

Discovering Antibacterial And Anti-Resistance Agents Targeting Multi-Drug Resistant Eskape Pathogens, Renee Fleeman

Graduate Theses and Dissertations

Antibiotic resistance has been a developing problem for mankind in recent decades and multi-drug resistant bacteria are now encountered that are resistant to all treatment options available. In 2014, the World Health Organization announced that this problem is driving us towards a “post-antibiotic era” that will change the face of modern medicine as we know it. If lack of novel antibiotic development and FDA approval continues, by the year 2050, 10 million people will die each year to an antimicrobial resistant bacterial infection. With lack of pharmaceutical industry involvement in developing novel antibiotics, the responsibility now lies within the academic ...


Non-Classical Regulators In Staphylococcus Aureus, Andy Weiss Apr 2017

Non-Classical Regulators In Staphylococcus Aureus, Andy Weiss

Graduate Theses and Dissertations

Staphylococcus aureus is a highly problematic human pathogen due to its ability to cause devastating infections, paired with a capacity to withstand the action of a large fraction of available antibiotics. Both pathogenicity and antibiotic resistance are encoded by numerous genomic elements, though the expression of these factors is energetically costly and not always beneficial for cellular survival. Therefore, S. aureus has developed sophisticated regulatory networks to integrate a multitude of signals, enabling it to navigate the delicate balance between its pathogenic lifestyle and baseline needs for cellular energy homeostasis. It is thus imperative to study S. aureus behavior and ...


A Novel Approach To The Discovery Of Natural Products From Actinobacteria, Rahmy Tawfik Mar 2017

A Novel Approach To The Discovery Of Natural Products From Actinobacteria, Rahmy Tawfik

Graduate Theses and Dissertations

Actinobacteria, primarily the genus Streptomyces, have led to the development of a number of antibiotics, which result from their secondary metabolites or modified derivatives. Secondary metabolite production can result from competition with neighboring microbes in an effort to disrupt growth, aiding in the competition for vital nutrients in impoverished conditions. Such secondary metabolites have the potential to affect a plethora of cellular functions in target cells, including, cell wall development, protein synthesis, protein function and fatty acid synthesis/metabolism. Due to the pandemic spread of antibiotic resistant bacteria, it is imperative to continue the search for new therapeutic agents targeting ...


A Novel Abi-Domain Protein Controls Virulence Determinant Production In Staphylococcus Aureus, Stephanie Michelle Marroquin Mar 2017

A Novel Abi-Domain Protein Controls Virulence Determinant Production In Staphylococcus Aureus, Stephanie Michelle Marroquin

Graduate Theses and Dissertations

A major factor in the success of Staphylococcus aureus as a pathogen is its vast arsenal of virulence determinants and, more importantly, the tight and precisely- timed regulation of these factors. Here we investigate the product of the S. aureus gene, SAUSA300_1984, encoding a putative transmembrane protein. This as yet uncharacterized protein belongs to the Abi (abortive infection) family, which are commonly annotated as CAAX-proteases, and are significantly understudied in prokaryotes. In S. aureus the disruption of SAUSA300_1984 results in a drastic reduction of proteolytic and hemolytic activity, as well as diminished pigmentation. This phenotype appears to be mediated through ...


The Genomic Evolution Of H1 Influenza A Viruses From Swine Detected In The United States Between 2009 And 2016, Shibo Gao Jan 2017

The Genomic Evolution Of H1 Influenza A Viruses From Swine Detected In The United States Between 2009 And 2016, Shibo Gao

Graduate Theses and Dissertations

Transmission of influenza A virus (IAV) from humans to swine occurs with relative frequency and is a critical contributor to swine IAV diversity. Subsequent to the introduction of these human seasonal lineages, there is often reassortment with endemic viruses and antigenic drift. To address whether particular genome constellations contributed to viral persistence following the introduction of the 2009 H1N1 human pandemic virus to swine in the USA, we collated and analyzed 616 whole genomes of swine H1 isolates. For each gene, sequences were aligned, the best-known maximum likelihood phylogeny was inferred, and each virus was assigned a clade based upon ...


Evaluation Of Maldi Biotyper For Identification Of Taylorella Equigenitalis And Taylorella Asinigenitalis, Kristina Lantz Jan 2017

Evaluation Of Maldi Biotyper For Identification Of Taylorella Equigenitalis And Taylorella Asinigenitalis, Kristina Lantz

Graduate Theses and Dissertations

Matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) has become an increasingly popular method for bacterial identification in recent years. Contagious Equine Metritis is a venereal disease of equids of international significance caused by the gram negative organism, Taylorella equigenitalis. The prescribed test is by bacteriological culture, however, due to the slow-growing and fastidious nature of the bacteria, culture requires specialized media and extended culture time. In addition, differentiation of T. equigenitalis and the closely related Taylorella asinigenitalis from each other and from common contaminants of the equine genital tract is difficult and has required advanced diagnostics with specialized ...


Emerging Swine Enteric Coronaviruses: Comparison Of Pathogenicity And Antibody Response, Kathleen A. Mayo Jan 2017

Emerging Swine Enteric Coronaviruses: Comparison Of Pathogenicity And Antibody Response, Kathleen A. Mayo

Graduate Theses and Dissertations

Porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV) recently emerged in the U.S. swine population resulting in an estimated loss of $481 - $929 million U.S. dollars in 2013-14. Both PEDV and PDCoV cause diarrheic disease resulting in dehydration, weight loss, and sometimes death. Although pigs of all ages are susceptible to these viruses, suckling piglets suffer the most severe disease. During 2013, PEDV associated pre-weaning morality rates approached 100% in naïve breeding farms. Many studies to date have demonstrated the significant impact of PEDV and PDCoV infections in pre-weaning piglets, but information on the diseases ...


Genetic And Phenotypic Characterization Of Livestock Associated Methicillin Resistant Staphylococcus Aureus Sequence Type (St) 5 In Comparison With Clinical St5 Isolates From Humans, Samantha Jean Hau Jan 2017

Genetic And Phenotypic Characterization Of Livestock Associated Methicillin Resistant Staphylococcus Aureus Sequence Type (St) 5 In Comparison With Clinical St5 Isolates From Humans, Samantha Jean Hau

Graduate Theses and Dissertations

Staphylococcus aureus is a commensal and pathogen of humans and other animals. Disease with S. aureus is complicated by dissemination of antimicrobial resistance, including methicillin resistance. Methicillin resistant S. aureus (MRSA) is a significant burden on the health care industry (HA-MRSA); however, in recent years, public health concern has arisen from isolates harbored in the community (CA-MRSA) and livestock species (LA-MRSA). Concerns with LA-MRSA isolates are the direct impact of infection with livestock isolates and indirect impacts of genetic transfer of virulence or antimicrobial resistance genes from LA-MRSA isolates. The prototypical LA-MRSA strain, sequence type (ST) 398, is considered less ...


Campylobacter In Cattle: Molecular Epidemiology And Antibiotic Resistance, Yizhi Tang Jan 2017

Campylobacter In Cattle: Molecular Epidemiology And Antibiotic Resistance, Yizhi Tang

Graduate Theses and Dissertations

Ruminant Campylobacter, (C. jejuni and C. coli), contributes significantly to foodborne illnesses in humans. A recently emerged C. jejuni clone (named SA) is also a major cause of ruminant abortion in the United States. Despite the importance of Campylobacter in ruminant health and food safety, little is known about its prevalence and antibiotic resistance profiles in cattle production systems in the U.S. In this project, we examined the antibiotic resistance susceptibility and mechanisms of the Campylobacter isolates derived from 35 feedlot cattle farms in 5 different states, and determined the distribution of C. jejuni clone SA in the feedlots ...


Evaluation Of Pre- And Post-Vaccination Influenza A Virus Antibody Responses In Breeding Age Replacement Gilts From Twelve Production Systems In The United States, James Scott Carlson Jan 2017

Evaluation Of Pre- And Post-Vaccination Influenza A Virus Antibody Responses In Breeding Age Replacement Gilts From Twelve Production Systems In The United States, James Scott Carlson

Graduate Theses and Dissertations

Influenza A virus (IAV) is an important respiratory pathogen of swine in the United States. Whole virus, inactivated vaccines are a common method used to control infection and clinical disease. However, homologous IAV vaccine antibody responses are rarely evaluated in the field and many influenza serological evaluations are lacking. New replacement gilts are an unstudied population in breeding farms and have been shown to affect viral ecology through introducing new IAV or lacking protection against resident viruses. Serological evaluations are uncommon in the current literature and could prove important in evaluating vaccine responses. This study sought to address all of ...


Impact Of Disease In Dairy Cows On Ceftiofur Pharmacokinetics, Withdrawal Times And Emergence Of Antimicrobial Resistance, Patrick John Gorden Jan 2017

Impact Of Disease In Dairy Cows On Ceftiofur Pharmacokinetics, Withdrawal Times And Emergence Of Antimicrobial Resistance, Patrick John Gorden

Graduate Theses and Dissertations

Producing safe and wholesome food is a priority of animal agriculture in order to maintain consumer confidence in the products produced by the animal agriculture industries. Antimicrobial residues and antimicrobial resistant organisms are two of the most important concerns of consumers regarding food safety. Withholding periods are in place to minimize the risk of antimicrobial residues being present in food. However, these withholding periods are established on healthy animals, not clinically ill animals. Additionally, there is no such withholding period in place to minimize the risk of transporting antimicrobial resistant organisms through food following treatment, although it has been proposed ...


Defining And Modulating The Butyrate-Producing Microbial Community In The Swine Gut, Julian Michael Trachsel Jan 2017

Defining And Modulating The Butyrate-Producing Microbial Community In The Swine Gut, Julian Michael Trachsel

Graduate Theses and Dissertations

Swine are an important agricultural commodity, and global swine production is increasing. Currently antibiotics are extensively used in commercial swine production for the treatment and prevention of diseases. However, the rise of antimicrobial resistance (AMR) necessitates that we reexamine our use of antibiotics, and reduce their use whenever possible. Alternatives to antibiotics are needed if we are to successfully mitigate AMR while still ensuring the health of swine and the safety of the food they produce. The intestinal microbiota is increasingly being manipulated in a number of ways to provide alternatives to antibiotic treatment, and progress is being made in ...