Veterinary Microbiology and Immunobiology Commons^™

Evaluation Of The Virulence Potential Of Avian Pathogenic Escherichia Coli Isolated From Broiler Breeders With Colibacillosis In Mississippi, Jiddu Joseph

Theses and Dissertations

Avian pathogenic Escherichia coli (APEC) is a bacterium that is responsible for colibacillosis in birds. However, information about broiler breeder APEC isolates is limited, but the data is critical due to the transfer of this bacteria down the production pyramid to progenies resulting in high mortality. Therefore, we evaluated the phenotypic virulence characteristics of 28 isolates using embryo lethality and day-old chick challenge assays. Also, the in vitro adhesion and invasion potential of selected nine isolates were identified. Results showed more than 1/3^rd of the isolates were highly virulent and the virulence increased as the number of virulence-associated genes …

Evaluating Vaccine Management Strategies For Edwardsiella Ictaluri Infections In Zebrafish (Danio Rerio), Brandy Malbrough

LSU Master's Theses

Aquaculture is a globally important industry that faces significant challenges due to infectious diseases, which can result in substantial financial losses. In 2011, a new strain of Edwardsiella ictaluri emerged as a major pathogen affecting zebrafish in the ornamental fish industry, leading to high mortality rates and posing a severe threat to the sector. Vaccines provide potential benefits for disease prevention in aquaculture, particularly live-attenuated vaccines (LAVs), which induce strong host immune responses. Bacterial attenuation for vaccine development has evolved from serial passage to more targeted genetic modification techniques. However, regulatory constraints limit the availability of licensed LAVs for aquaculture. …

Design, Construction, And Testing Of Recombinant Dna-Based Vaccines For Protection Against Salmonella Enterica Subspecies Enterica Serovar Javiana, Ashley Edwards

LSU Doctoral Dissertations

In the United States, Salmonella Javiana is among the top 5 most common nontyphoidal Salmonella serotypes, with a 325% increase in infection rate since 1970. Globally, nontyphoidal Salmonella leads to approximately 93.8 million illnesses and 155,000 deaths annually, with disproportionate impacts in developing countries. In the United States alone, these infections lead to over $4 billion in costs, the majority of which are attributed to those expenses incurred from mortalities. The zoonotic nature of nontyphoidal Salmonellae and their ability to survive on and within vegetation mean huge economic burden potential for various agricultural industries as well, especially since some of …

Equine Fecal Microbiota Response To Short Term Antibiotic Administration, Jordan Lacey Parker

Theses and Dissertations--Veterinary Science

Though generally regarded as safe, research continues to demonstrate negative side effects of antibiotic administration on the gastrointestinal (GIT) microbiota across species. In horses, antibiotic associated diarrhea (AAD) is a life-threatening side effect linked to the GIT microbiota. This study tested the hypothesis that short term antibiotic administration to healthy horses would negatively impact the fecal microbiota as measured by their ability to digest nutrients and produce short chain fatty acids (SCFAs). Twenty-four horses were assigned to one of four treatments: control (CO); potassium penicillin/gentamicin sulfate (KPG); ceftiofur crystalline free acid (EX); trimethoprim/sulfamethoxazole (SMZ); and treated for 4 days. Fecal …

Comparison Of The Humoral Immune Response Following Both Bacterial Challenge And Rnai Of Major Factors On Proliferation Of Bartonella Quintana In The Human Louse, Jake Zina

Masters Theses

Human body lice, Pediculus humanus humanus, and head lice, Pediculus humanus capitis, have been hematophagous ectoparasites of humans for thousands of years. Despite being ecotypes, only body lice are known to transmit bacterial diseases to humans, and it appears that lower humoral and cellular immune responses allow body lice to possess a higher vector competence. We previously observed that the transcription level of the defensin 1 gene was up-regulated only in head lice following oral challenge of Bartonella quintana, a causative agent of trench fever, and also that body lice excreted more viable B. quintana in their …

Bacterial Chondronecrosis With Osteomyelitis In Broilers: Genomics, Phylogenomics, And Methods To Detect Specific Pathogens During Outbreaks., Abdulkarim Abdulaziz A. Shwani

Graduate Theses and Dissertations

Lameness is a major issue in animal welfare and the broiler industry. Bacterial chondronecrosis with osteomyelitis (BCO) is one of the main causes of lameness. Many staphylococcal species, including Staphylococcus agnetis isolate 908, have been isolated from the bones and blood of lame broilers at the University of Arkansas. Staphylococcus agnetis is a coagulase-variable, Gram-positive bacterial species that has been previously associated with subclinical or mild clinical cases of mastitis in dairy cattle. The annotated complete genome of hypervirulent strain 908 was published at NCBI. In this study, it has been compared to nine genomes we assembled for hypervirulent isolates …

Evaluation Of Residual Antibacterial Effects On Canine Skin Surface And Hairs Following Treatment With Five Commercial Mousse Products Against Staphylococcus Pseudintermedius In Vitro, Chi-Yen Wu

LSU Master's Theses

Topical products are essential treatments for canine superficial bacterial folliculitis. However, studies for commercial products typically evaluate antibacterial effects on hairs rather than the skin surface. In addition, the interference from the hair length has not been evaluated in these studies. Therefore, the study objective for this study was to evaluate the residual antibacterial effects of five mousse products, (1) 2% chlorhexidine and 2% miconazole, (2) 0.05% phytosphingosine, (3) 2% salicylic acid and 10% ethyl lactate, (4) 3% chlorhexidine and 0.5% climbazole, and (5) 2% chlorhexidine and 1% ketoconazole on both the skin surface and hairs in both short- and …

Characterization Of The Fecal Microbiome In Dogs Receiving Medical Management For Congenital Portosystemic Shunts, Nathan Squire

Masters Theses

Background: The GI microbiome has not been characterized in dogs being medically managed for congenital portosystemic shunts [CPSS].

Objectives: To characterize the fecal microbiome in a population of dogs being medically managed for CPSS.

Animals: 27 client-owned dogs.

Methods: Prospective cohort study enrollment of fecal samples was performed with follow-up data collected retrospectively. The overall fecal dysbiosis index [DI] and individual bacterial abundances were determined using real-time qPCR. Medical management, clinical findings, clinicopathologic, and outcome variables were collected, and logistic regression analyses were performed to evaluate associations between these variables and overall DI and bacterial abundances. Numerical variables were evaluated …

Time Course Investigation Of The Dermal Leukocyte Response To Lipoteichoic Acid In Chickens, Ian Gilbert

Animal Science Undergraduate Honors Theses

Lipoteichoic acid (LTA) is component of the cell wall of Gram-positive bacteria that stimulates inflammation during bacterial infection. However, few studies have investigated the in vivo immune response to LTA, and none of the in vivo studies done have been performed in birds. For this project, the pulp (a skin-derivative) of growing feathers (GFs) of chickens were used as a test site to investigate the in vivo effects of intradermally injected LTA. In Study 1, the pulp of 12 GFs of 11-week-old Light-brown Leghorn (LBL) males were injected with 10 μL of differing concentrations of LTA (0.1, 1.0, 10, 100 …

The Effects Of Cannabidiol On Senior Equine Health, Shelley Turner

Theses and Dissertations--Veterinary Science

Cannabis sativa L., has been revealed to produce hundreds of phytocannabinoids, of which cannabidiol (CBD) is one of the most desired. It has been revealed that CBD can potentially treat inflammation and act as an analgesic in humans without psychoactive effects of delta-9-tetrahydrocannabinol (THC). Recently, there has been interest in understanding the potential health benefits of CBD for horses. With an increasing senior horse population (< 15 years old), alternatives to the use of non-steroidal anti-inflammatory drugs (NSAIDs) such as phenylbutazone, firocoxib, and flunixin meglumine, are desired as these common anti-inflammatory treatments have negative side effects. Because senior horses may have chronic low-grade inflammation, termed inflamm-aging, they are a natural model to investigate the efficacy of CBD on inflammatory responses as well as other health parameters. Given this interest, and due to the lack of research conducted on CBD in the horse, the overall objective of this dissertation work was to conduct both basic and applied research investigating the effects of CBD on equine immune function and health. The first objective was to determine the in vitro effects of CBD as an anti-inflammatory. Peripheral blood mononuclear cells (PBMCs) from senior horses were cultured in vitro with increasing concentrations of pure CBD dissolved in dimethyl sulfoxide (DMSO). These cells were …

Role Of Host Restriction Factors On Porcine Reproductive And Respiratory Syndrome Virus (Prrsv) Replication, Pratik Katwal

Electronic Theses and Dissertations

In this study, the role of IFITM3 on PRRSV replication was studied in vitro by expressing exogenous IFITM3 in MARC-145 cells. An average of 31% reduction in PRRSV N protein expression and an average of 5.4 fold decrease in virus titer in the supernatant were observed in IFITM3 overexpressing cells as compared to vector control cells at 24 hours post infection (hpi). Moreover, there was a positive correlation between interferon- induced IFITM3 up-regulation and reduced PRRSV replication. To determine the role of endogenous IFITM3 in PRRSV replication, siRNA induced knockdown of IFITM3 was employed. RT-PCR validated the successful silencing of …

Genistein-Enriched Pig Gut Microbiota Library As A Potential Probiotic Consortium, Theresah Amponsah

Electronic Theses and Dissertations

Plant-based diets contain numerous flavonoid compounds that produce antibacterial effects and gut health improvement. Genistein is among the most abundant isoflavones present in a plant-based diet and can be found in high amounts in soy products (up to 1g Kg-1). We describe here a robust method to identify genistein tolerant and metabolizing bacteria in swine gut microbiota and to screen the strains that have antibacterial and immunestimulatory properties. Such strains could be developed as non-antibiotic alternatives to prevent enteric infections in pigs and improve gut immunity. To this end, a mini bioreactorbased system was used to enrich genistein metabolizing bacteria …

Emerging Respiratory Viral Pathogens, April Nelsen

Electronic Theses and Dissertations

Respiratory disease is arguably the most important health concern for the production animal industry [1-3]. Respiratory problems accounted for the highest mortality both in the swine and beef industries [1, 4]. Respiratory pathogens remain the most vital for swine and bovine research and disease monitoring [2, 5-7]. As pathogens, in particular viral pathogens, mutate, novel disease-causing viruses emerge, and there becomes an increasing concern and need for identification with control perimeters. One frequently identified disease syndrome is Porcine Respiratory Disease Complex (PRDC). PRDC is characterized by pneumonia of mixed respiratory infections with contributions from the environment and management practices. The …

A New All-Natural Wound Treatment Gel Shows Strong Inhibitory Activity Against Staphylococcus Aureus And Other Wound Pathogens, Tasha K. Nelson

Electronic Theses and Dissertations

Skin related injuries are some of the most dangerous forms of wounds. In addition to treating the wound itself, health care providers must be cautious of microbial infections. In this study, we evaluate a novel all-natural antimicrobial gel compound (AMG) designed to kill planktonic bacteria, penetrate bacterial biofilms, and accelerate wound healing. In -vitro experiments demonstrate that AMG is effective in inhibiting planktonic growth and biofilm development of eight common pathogens. LIVE/DEAD staining and confocal microscopy reveal that planktonic growth and three-dimensional structure of biofilms were significantly reduced. Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) was used to investigate a small …

Differentiation Of The Can F 1 Allergen In Hypoallergenic Dog Saliva Compared To Shedding Dog Saliva, Rose Miller

Honors College Theses

Dog saliva contains a large variety of proteins, each with specific functions throughout the body. While some aid in digestion, others provide immune support for the body. In the case of human dog allergies, dog skin dander has been proven to cause allergic reactions to those who are sensitive to the allergens in the dogs. However, past studies have shown a difference in allergic reaction to specific breeds, breaking dog breeds into two main categories: hypoallergenic and non-hypoallergenic. Within these groups, there are different hypoallergenicity levels, but overall, the hypoallergenic dog group does not cause an allergic reaction, whereas non-hypoallergenic, …

Characterization Of Memory T-Lymphocyte Subsets In Dogs, Annie Beth Bauman

LSU Master's Theses

A more complete understanding of canine T-cell immunity is necessary for improving diagnostic and therapeutic approaches to canine diseases, developing cell-based canine immunotherapeutics, and evaluating dogs as large mammal models for comparative immunology research. Canine immunological studies are limited by the lack of established phenotypic markers identifying diverse differentiation states in canine T-cells. Differential expression of CD45RA (indicating antigen experience) and CD62L (indicating lymph node homing capability), shows promise as a tool to delineate canine naïve (TN), central memory (TCM), effector memory (TEM), and terminal effector memory (TEMRA) T-cells. The aim of this study was to characterize canine memory T-cell …

Muscle Mass And Immune Function In The Senior Horse, Alisa Christina Herbst

Theses and Dissertations--Veterinary Science

Senior horses (≥ 15 years) represent up to one-third of the global equine population, and the proportion of old horses (≥ 20 years) in the U.S. has been steadily increasing. Aging is associated with a loss of skeletal muscle mass in horses, and while age-related muscle loss is comparingly well characterized in humans, little is currently known concerning underlying mechanisms, adverse outcomes, or the prevalence of low muscle mass in senior horses. One factor proposed to play a role in the development of age-related muscle atrophy in humans is inflamm-aging, a low-grade inflammation that affects elderly people and that has …

Viral And Immune Studies On Bovine Viral Diarrhea Virus (Bvdv) In Bovine Species, Karim Abdelsalam

Electronic Theses and Dissertations

BVDV is a major pathogen of ruminants that causes immune dysfunction and lead to secondary bacterial infection. The underlying mechanism of this dysfunction is not well understood. Based on previous results, we believe that macrophages play a central role in BVDV-associated immune dysfunction. Previously, we have shown that the infected monocyte-derived macrophage (MDM) supernatant of the high virulent strains of BVDV significantly induced lymphocyte apoptosis. In the current study, we performed experiments to identify the apoptotic factors in the infected MDM supernatants in vitro. Also, we have extended our investigation to include testing the impact of infected macrophages on neutrophil …

Molecular Detection Of Aquatic Bird Bornavirus In Waterfowls In Calamba, Laguna, Gio Tristan J. Esguerra

Undergraduate Theses

Waterfowls are believed to be reservoirs and transmitters of aquatic bird bornavirus. The virus targets the central and peripheral nervous system and causes neurologic abnormalities and/or gastrointestinal dysfunction due to the involvement of the gastrointestinal autonomic nervous system. Infected waterfowls are typically asymptomatic and tend to be lifelong carriers and long-term shedders of the virus. A total 81 fecal samples were collected from five enclosures housing various species of waterfowls from an aviary in Calamba, Laguna. The samples were analyzed by RT-PCR using primers that target a highly conserved region of the matrix (M) gene located between nucleotide positions 1911 …

An Assessment Of The Carrier State And A Novel Marker Of Leptospira And Abortion In Central Kentucky Horses, Gloria Louise Gellin

Theses and Dissertations--Veterinary Science

Leptospirosis is a reemerging zoonotic infection of worldwide importance and affects all mammals. The bacterium is transmitted to animals and humans by urine, fetal membranes and body fluids. Leptospira shedding in the urine contaminates both soil and water, exposing both humans and animals to the bacterium. Leptospirosis in horses can cause abortion and is one of the etiologies of equine recurrent uveitis which can lead to blindness. Equine leptospiral abortion in Central Kentucky is primarily caused by serovar Pomona, with occasional cases attributed to serovar Grippotyphosa. There are a few reports in the literature attributing abortion to serovar Bratislava in …

Impact Of Endangered Animal Protection Rights, Policies, And Practices On Zoonotic Disease Spread, Daniella Fedak-Lengel

Honors Projects

Building on field research in Costa Rica and Belize, this honors project analyzes environmental and endangered animal protection policies, rights, and practices in Central America and the Caribbean, and assesses the impact of veterinary science and biological research and practice, particularly conservation biology, on animal welfare concerns. Informed by the recent surge in awareness regarding zoonoses and zoonotic disease transmission, prevention and control, resulting from the current global pandemic of SARS-CoV-2, the project assesses the need for new and innovative types of collaboration, particularly involving conservation biologists, environmental scientists, public health experts, law and policy makers, and global trade and …

Host-Parasite Interaction In Horses: Mucosal Responses To Naturally Acquired Cyathostomin Infections And Anthelmintic Treatment, Ashley Elaine Steuer

Theses and Dissertations--Veterinary Science

Cyathostomins are ubiquitous parasites in equids. In rare cases, cyathostomins lead to a generalized typhlocolitis and death. In healthy horses, local reactions are noted to the mucosal larvae; however, the mechanisms and importance of these reactions have not been elucidated. It has been hypothesized that anthelmintics can alter these reactions. Currently, three drug classes are approved for use in horses against cyathostomins; while all products target the adults, only two products are labeled as larvicidal. Adulticidal therapy is implicated in triggering the typhlocolitis, however, current evidence is contradictory. There is also conjecture that the larvicidal drugs can increase the risk …

Evaluation Of Rhodococcus Equi Susceptibility To Silver Nanoparticle Antimicrobials, Elizabeth Boudaher

Theses and Dissertations--Veterinary Science

Rhodococcus equi is a significant cause of pneumonia in foals and immunocompromised humans. Antimicrobial resistance among R. equi isolates has developed as a consequence of inappropriate stewardship and bacterial evolution, leading to an increased rate of treatment failures that typically result in foal fatality. In the current study, we evaluated the efficacy of antimicrobial silver nanoparticle (AgNP) complexes in controlling R. equi growth. Previous studies characterizing AgNP-induced antibacterial effects in other Gram-positive pathogens led us to hypothesize that silver nanoparticle antimicrobials impact R. equi viability and intracellular replication. We therefore investigated the effect of silver nanoparticle complexes on R. equi …

Nlrp6 In Gram-Positive Pneumonia And Sepsis, Laxman Ghimire

LSU Doctoral Dissertations

Acute lower respiratory infections (pneumonia) and pneumonia-derived sepsis are among the leading causes of death in the world causing 7.8 million deaths annually. In this regard, Methicillin-resistant Staphylococcus aureus (MRSA) is endemic in the US and implicated for causing high mortality-associated necrotizing pneumonia and aggravating viral pneumonia with superinfection. Additionally, sepsis is the 7^th leading cause of death among newborns in the US and is responsible for more than 750,000 hospitalization cases every year. Although there is a plethora of research in both pneumonia and sepsis, the detailed pathophysiology still remains elusive. Understanding the host defense mechanism will help …

Preparation And Evaluation Of Single-Stranded Dna Aptamer-Based Immunological Adjuvant In Broiler Chickens, Adil Sabr Al-Ogaili

Graduate Theses and Dissertations

Mineral oils and metal salts are commonly used as adjuvants to enhance acquired immunity. Recently, monoclonal antibodies (MAbs) and recombinant peptides agonist CD40 receptor have shown remarkable promise for induction of rapid and robust immune responses. Limitations of this approach MAb production costs and multiple administrations due to anti-MAb immune responses. Here we demonstrate the development of a unique and sophisticated DNA aptamer-based alternative for CD40-directed delivery of universal antigens as an alternative in chickens, and potentially other vertebrate species. This receptor, expressed by antigen-presenting cells, acts as a costimulatory molecule for activated T helper lymphocytes. After initially selecting for …

Young Germ Cell Depleted Ovaries In Post-Reproductive Mice And Its Effects On Immune Function, Mckenna Walters

Undergraduate Honors Capstone Projects

It has previously been shown that young, cycling ovarian transplantation in aged female mice increased the general health and life span in regard to their post-reproductive health. It has further been hypothesized that this enhancement of health is directly influenced by the ovarian somatic cells. To address this hypothesis, transplants of young germ cell depleted and germ cell containing ovaries were performed on female mice. The purpose of this study is to continue to discern the reproductive influence on aging health, specifically in the area of immunological well-being. Control group mice were separated by age and treatment mice were subsequently …

Evaluación Molecular, De Ehrlichia Canis Y Babesia Canis En Caninos Militares De La Fuerza Aérea Colombiana, César Enrique Martínez Roa

Maestría en Ciencias Veterinarias

La Ehrlichiosis Monocítica Canina (EMC) y la Babesiosis Canina, son patologías de distribución mundial causadas por Ehrlichia canis y Babesia canis, respectivamente, comparten vector (Rhipicephalus sanguineus) y existen reportes en Colombia de infección individual y co-infección. La Fuerza Aérea Colombiana (FAC) cuenta con caninos entrenados en detecciones. En las Unidades de clima cálido del año 2008 al 2012, se ha reportado una alta tasa de mortalidad presuntivamente EMC, sin diagnóstico confirmado. Reemplazar un animal fallecido tiene altos costos económicos e intangibles (tiempo y capacidades adquiridas), por ello surge la necesidad de confirmar la posible presencia E. canis y B. canis …

Rumen Microbial Culture Library And In Vitro Analysis Of Selected Bacterial Species On Colonization Resistance Against Bovine Enteric Pathogens, Maria Antony

Electronic Theses and Dissertations

The anaerobic habitat of the four chambers in ruminant’s foregut plays a vital role in the fermentation of the food by the active involvement of the residing microbial community. The cultivability and the potential role of rumen bacteria in the field of livestock production, host health and immunity are important to study. The developed anaerobic culturing techniques enable us to culture and screen different rumen bacteria to study the anti-pathogenic effects. Whole genome sequencing and analysis help us to understand the genome level characteristics of the rumen bacterial species individually. Since the majority of the rumen biosphere is still not …

Bovine Cellular And Innate Immune Response To Hemostatic Polysaccharides, Brian Kobylkevich

Electronic Theses and Dissertations

Chronic wounds are longstanding dermal wounds that do not heal in a normal amount of time and can commonly last for over a year. These wounds plague humans and farm animals alike. Wounds are characterized by chronic inflammation and are often painful, difficult to heal, have a high recurrence rate, and are potentially debilitating. Long term wounds that do not fully heal are distressing for both humans and animals, but understandably more resources have been directed towards humans. Some treatment options for humans may be suitable for adaptation into the field of animal care. Chronic lesions such as bovine digital …

Effects Of Pituitary Pars Intermedia Dysfunction And Prascend® Treatment On Endocrine And Immune Function In Senior Horses, Ashton B. Miller

Theses and Dissertations--Veterinary Science

Pituitary pars intermedia dysfunction (PPID) is one of the most common endocrine diseases affecting senior horses. PPID causes abnormally high concentrations of adrenocorticotropic hormone (ACTH) in the plasma and a very distinct, long, shaggy haircoat (hypertrichosis). At present, the recommended treatment for PPID is daily oral administration of pergolide mesylate. Due to the increased ACTH levels associated with PPID, it is commonly thought that these horses are immunosuppressed and at increased risk of opportunistic infections, although current research in this area is sparse. Additionally, it is not well-understood how treatment with Prascend^® (pergolide tablets) affects endocrine measures other than …