Veterinary Microbiology and Immunobiology Commons^™

Surveillance Of A Novel Vesivirus Discovered In An Urban Mephitis Mephitis Population, Amanda E. Diggins

Honors Theses and Capstones

Caliciviridae is a family of non-enveloped, positive-sense, single stranded RNA viruses, including eleven defined genera that contain important pathogens of humans and animals. Within the Caliciviridae family, the genus Vesiviridae includes feline calicivirus, a leading cause of upper respiratory disease in cats, and vesicular exanthema of swine virus, a historical disease of domestic swine that has now been implicated in several marine mammal vesicular diseases, one of which has been confirmed zoonotic. Urban landscapes create a unique environment for rapid intra- and interspecies transmission of viruses. Clustered resources attract high-density populations of synanthropic wildlife species, increasing spatial overlap and heightening …

The Impact Of A Nf-Κb Signaling Inhibitor On The Antibacterial Activity Immune Response In The Cat Flea (Ctenocephalides Felis), Caroline M. Singer

College of Graduate Studies: Theses & Dissertations

Ctenocephalides felis are vectors of several bacterial pathogens that cause disease in humans and animals, including Bartonella henselae and Rickettsia felis. Successful pathogen transmission requires that microbes survive the immune defenses of the flea digestive tract following blood feeding. In insects, humoral immune responses are regulated primarily by the Toll and immune deficiency (IMD) signaling pathways, with the IMD pathway serving as the principal defense against Gram-negative bacteria. Although genomic and transcriptional evidence indicate that cat fleas encode and express components of the IMD signaling pathway, the functional roles of individual pathway components within the flea digestive tract remain …

Engineering Novel Biomimetic Models Of Equine Host-Microbe Interactions, Lynn M. Leedhanachoke

Theses and Dissertations--Veterinary Science

One major limitation to the study of equine disease is the lack of in vitro models that accurately reflect the dynamic physiology of the horse. Thus, there is a pressing need to develop in vitro systems that recapitulate diverse equine tissue and organ microenvironments. To overcome this deficiency, we developed multiple biomimetic equine organoid systems that can be employed for a variety of investigations aimed at resolving outstanding questions in infectious disease pathogenesis, therapeutic development and drug metabolism, host defense mechanisms, immune-modulated disease, and equine developmental biology. Our innovative platform incorporates novel equine intestinal enteroid and airway organoid models derived …

The Effect Of A Lactobacillus Containing Gel On The Clitoral Microbiome Of The Mare, Fiona E. Herzog

LSU Master's Theses

The equine lower reproductive tract harbors bacterial populations that serve as a reservoir for potential pathogens. Dysbiosis of urogenital sites may play a role in reproductive disease of the mare, including endometritis. Metagenetic studies have evaluated microbiomes in the uterus, vagina and placenta, while the clitoral microbiome has yet to be described. In this study, the following hypotheses were tested; 1) the clitoris harbors a unique microbiome, 2) topical Lactobacillus genus complex (LGC) probiotic will alter this microbiome, 3) acceptable per cycle pregnancy rates (PCPR) following probiotic application will be achieved. Reproductively normal mares (n=14) were selected, and clitoral fossa …

Isolation, Molecular Characterization, And Epidemiological Analysis Of An Emerging Avian Metapneumovirus Subgroup B In Us Poultry, Sumit Jangra

Electronic Theses and Dissertations

Avian metapneumovirus (aMPV) is one the most economically important poultry respiratory pathogens belonging to the family Pneumoviridae and genus Metapneumovirus, which can affect both domestic and wild birds. aMPVs are classified into four subgroups (A, B, C, and D) based on the level of genetic variations and antigenic differences. aMPV causes turkey rhinotracheitis (TRT) and swollen head syndrome (SHS) in turkeys and chickens respectively. Recently, outbreaks of respiratory disease in meat-type birds and a significant decline in egg production with respiratory signs in breeders were reported from different states in the USA. Isolating aMPV is challenging as it is a …

Abelson (Abl) Tyrosine Kinase Inhibitors Reduce Porcine Reproductive And Respiratory Syndrome Virus (Prrsv) Replication In Vitro, Jenna Parliament

Electronic Theses and Dissertations

Porcine reproductive and respiratory syndrome virus (PRRSV) is an enveloped, positive-sense, single-stranded RNA virus from the Arteriviridae family. PRRSV causes respiratory illness and reproductive failure in infected pigs. Outbreaks occurring in the United States and worldwide cause significant economic losses annually. Abelson (Abl) tyrosine kinase is a non-receptor tyrosine kinase, which plays a central role in regulating many cellular processes such as actin reorganization, cell proliferation and differentiation by transducing extracellular and intracellular signals. Abl inhibitors have been shown to restrict the entry of membrane fusion of enveloped viruses, such as severe acute respiratory syndrome coronavirus, Middle Eastern respiratory syndrome …

Increased Coding Potential Of Bovine Herpesvirus 1, Victoria Jefferson

Theses and Dissertations

Bovine respiratory disease (BRD) costs the cattle industry millions of dollars in costs in treatment and loss every year in the United States. A significant pathogen often contributes to BRD is Bovine Herpesvirus 1 (BoHV-1), a double stranded DNA virus with the ability to establish latency in the trigeminal ganglia and neurons. Primary infection with BoHV-1 results in immunosuppression that increases the risk of secondary bacterial infection and pneumonia. Because herpesviruses infect their hosts for life and can be reactivated in times of stress, BoHV-1 can present a recurring risk of BRD. The following research aims to expand the knowledge …

Nutritional Strategies To Reduce Salmonella Enteritidis Infections In Laying Hens: Prebiotic, Probiotic, And Precision Biotics, Ishab Poudel

Theses and Dissertations

Salmonella Enteritidis (SE) infections in laying hens is a significant cause of foodborne illness linked to the consumption of contaminated eggs. This dissertation encompasses novel strategies aimed to explore appropriate in-vitro and in-vivo models to evaluate the effects of these novel strategies to reduce SE in laying hens. Firstly, we investigated the potential probiotics, prebiotics, and essential oil combinations to reduce SE in-vitro. The results showed that probiotics and prebiotics are equally effective to reduce SE. In subsequent studies, we evaluated the role of vaccination history on cecal microbiota and SE infections with various doses of oral SE challenge. …

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 …

Corticosterone Measurement In A Cryptosporidium-Positive Population Of Louisiana Pine Snakes (Pituophis Ruthveni), Corinne Mayer

LSU Master's Theses

Louisiana pine snakes (Pituophis ruthveni) are one of the rarest snake species in North America, and federally classified as “threatened” (United States Fish and Wildlife, 2018). Recent establishment of sustainable captive breeding populations combined with decades of field research by conservation biologists has led to several advancements in our knowledge of this species; however, further investigations into health parameters and the physiology of this species are needed to optimize management of captive populations.

One recent investigation highlighted the difficulties in reliably differentiating the sexes in P. ruthveni using traditional tail probing techniques (Katz et al., 2020). Prior to …

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 …

Understanding Human Gut Bacterial Interactions And Their Role In Colonization Resistance Against Clostridioides Difficile Using Mini-Bioreactor Array And Caenorhabditis Elegans As Model Systems, Achuthan Ambat

Electronic Theses and Dissertations

No abstract provided.

The Role Of Microbiota-Biotransformed Bile Acid Metabolites On Campylobacter Jejuni- And Clostridium Perfringens-Infection, Ying Fu

Graduate Theses and Dissertations

Campylobacter jejuni (C. jejuni) and Clostridium perfringens (C. perfringens) are two leading pathogenic bacteria responsible for both human and animal diseases. In chapters Ⅱ to Ⅳ, I presented an overview of current knowledge on the role of immune response, microbiota, bile acids and their microbial metabolites on campylobacteriosis, and C. perfringens induced necrotic diseases.In chapter Ⅴ, I investigated effects of deoxycholic acid-modulated anaerobes (DCA-Anaero) on attenuating chicken transmission-exacerbated campylobacteriosis. SPF Il10-/- mice were gavaged with clindamycin for 7 days followed by infected with three C. jejuni strains, Cj-P0 (C. jejuni AR101), Cj-P1 (from chicken pre-infected with C. jejuni AR101), and …

The Role Of Temperature Variation On Macrophage Physiology And Function In Vitro In Mice, Chicken, And Fish, Intisar Abdullah Hassan

Graduate Theses and Dissertations

Fever is an essential component of the immune response. Baseline body temperatures vary in different species, and fever represents increased temperature over baseline. Fever initiates and enhances immune responses as well as creates an environment in which the body has advantages over pathogens. Macrophages are often the first line of cells that come in contact with pathogens, asthey reside in and traffic through tissues. They are important for their engulfment of pathogens that results in the digestion of the pathogen, and they also produce nitric oxide and cytokines that contribute to immune responses in a variety of ways, including initiating …

Chondronecrosis With Osteomyelitis In Broilers: Bacterial Species Involvement And Influence Of Probiotics And Synbiotics, Amer Abdullah Hasan

Graduate Theses and Dissertations

Since 1945, the market for broiler production has evolved from a collection of smallholder poultry farms into an industry worth billions of dollars. Poultry production has not gone without challenges. Lameness in young broilers is presently a serious issue in the poultry industry for reasons of animal health and welfare, as well as significant lost production and revenue. Bacterial chondronecrosis with osteomyelitis (BCO) is a major form of lameness in broilers. This dissertation contains information about (i) the influence of Staphylococcus agnetis, Staphylococcus saprophyticus, Staphylococcus epidermidis and Enterococcus faecalis on inducing BCO lameness, (ii) evaluation of of probiotics for reducing …

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 …

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 …

Novel Roles For Viral Gpcrs In Cmv Latency And Immunity, Timothy White

LSU Doctoral Dissertations

Human cytomegalovirus (HCMV) is a widespread, highly prevalent pathogen with severe consequences in vulnerable populations. HCMV and the related murine cytomegalovirus (MCMV) encode multiple G protein-coupled receptor (GPCR) homologs which are involved in latency, immune evasion, and tissue tropism and dissemination. In this work, we investigate the mechanisms of two CMV-encoded GPCR homologs, HCMV US28 and MCMV M33, in latency and T cell immune evasion. Chapter 2 describes the isolation and immortalization of a salivary gland-derived mesenchymal cell line, termed mSGM. These cells are permissive to MCMV infection and express all three BALB/c mouse MHC class I isotypes, making them …

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 …

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 …

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 …

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 …

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 …