Veterinary Medicine Commons^™

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 …

Regenerative Medicine For Tendon/Ligament Injuries: De Novo Equine Tendon/Ligament Neotissue Generation And Application, Takashi Taguchi

LSU Doctoral Dissertations

Tendon and ligament injuries are debilitating conditions across species. Poor regenerative capacities of these tissues limit restoration of original functions. The first study evaluated the effect of cellular administration on tendon/ligament injuries in horses using meta-analysis. The cellular administration was effective in restoring ultrasonographic echogenicity and increasing vascularity during early phase of healing. Additionally, it improved microstructural organization of healed tissue in terms of cellularity and fiber alignment. However, the study did not support its use for increasing rate of return to performance, expression/deposition of tendon-specific genes/proteins, or mechanical properties.

The findings led to the second study that engineered implantable …

Contribution Of The Microbiome On Reproductive Outcomes During Pregnancy, Kalie Beckers

LSU Doctoral Dissertations

A series of translational comparative studies were performed to investigate the effects of the maternal microbiome on reproductive function and outcomes. With the launch of the human microbiome project in 2007, the next generation sequencing of microbiomes is booming. It is not only in the human medicine field, but also in veterinary species. This study specifically investigates the fecal microbiome in blood pressure high sublime 5 (BPH/5) mouse model that spontaneously develops preeclampsia (PE) and obesity. Additionally, the equine reproductive tract microbiome was explored and compared to microbiome of other host body sites. The BPH/5 mouse is a translational model …

Evaluation Of Hippocampal Allostatic Load-Associated Factors In Animal Models Of Post-Traumatic Stress Disorder: Relevance To Human Ptsd, Dennis Parker Kelley

LSU Doctoral Dissertations

Post-traumatic stress disorder (PTSD) is associated with elevated allostatic load, nearly double the risk for metabolic syndrome, reduced hippocampal volume, and contextual memory processing deficits. Emerging evidence suggests that these stress effects may predispose individuals to the development of PTSD, and there is a known relationship between chronic stress and metabolic dysfunction. In this work, we utilized two rat models of PTSD to explore these connections. We used an acute predator odor stressor to investigate the relationship between PTSD-like behaviors and mitochondrial dysfunction in the hippocampus of rats, and we observed that conditioned place avoidance was associated with reduced mitochondrial …

Embryo Development And Reproductive Parameters Of Aluteal Cycles In Mares, Chun Kuen Mak

LSU Doctoral Dissertations

Progestagen is crucial for regulating early pregnancy in most mammalian species, including the horse. This dissertation research sought to elucidate the effect of endogenous and exogenous progestagens on the early development of equine embryos and to characterize reproductive parameters in the subsequent estrus using a prostaglandin F_2α-induced hypoluteal environment, namely the aluteal pregnancy model. The first chapter reviewed the life cycle of the corpus luteum and its progesterone secretory function in mares. The existing literature supports the notion that the early developing corpus luteum is responsive to prostaglandin F_2α, and complete luteolysis or prevention of luteal …

Edwardsiella Ictaluri Is Capable Of Persisting In Channel Catfish By Evading Host T Cell And Cell Death Responses, Elizabeth Watts Griggs

LSU Doctoral Dissertations

Edwardsiella ictaluri is a gram-negative bacterium of the family Enterobacteriaceae that infects and causes enteric septicemia (ESC) of channel catfish (Ictalurus punctatus), a fatal disease costing the catfish industry millions of dollars in losses each year. Edwardsiella. ictaluri is capable of replicating in catfish head-kidney-derived-macrophages (HKDM), and like many other gram-negative bacteria, E. ictaluri encodes a Type III Secretion System (T3SS) that is required for virulence and intracellular replication. In the case of E. ictaluri, the T3SS translocates effectors from the Edwardsiella containing vacuole (ECV) through the bacterial cell wall and the vacuolar membrane directly to the …

Equine Hoof Stratum Internum K14+Cd105+ Progenitor Cells: Culture, Characterization, And Model Of Epithelial To Mesenchymal Transition, Qingqiu Yang

LSU Doctoral Dissertations

For the potential benefit of progenitor cells to be realized in cell-based clinical therapies, it is vital to investigate the mechanism between progenitor cells and abnormal tissue formation. Laminitis is a fatal condition that is often presented by equine hoof inflammation and hoof tissue disarrangement. The persistence of abnormal tissue formation after the resolution of equine laminitis suggests there is progenitor cell compromise. So far, there is limited information about equine hoof progenitor cells and the effects of inflammation on hoof progenitor cells. To pursue a better understanding of both hoof progenitor cell and hoof growth as well as find …

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 …

Characterization Of Bunyamwera, Batai, And Ngari Viruses: Unrecognized Arboviruses Of One Health Importance In Rwanda, Marie Fausta Dutuze

LSU Doctoral Dissertations

Bunyamwera (BUNV), Batai (BATV), and Ngari (NRIV) are mosquito-borne viruses (Genus: Orthobunyavirus, Family: Peribunyaviridae, Order: Bunyavirales). They have an RNA tripartite genome consisting of small (S), medium (M), and large (L) segments. NRIV is a natural reassortant of BUNV and BATV, with the genome: S_BUNV, M_BATV, L_BUNV. All three viruses have been associated with disease of varying severity in domestic ruminants and humans. In livestock, infection with these viruses is associated with abortions, while humans may present a mild febrile illness or severe disease such as hemorrhagic fever or meningoencephalitis. In East Africa, …

Neurostimulator With Waveforms Inspired By Nature For Wearable Electro-Acupuncture, Jose Aquiles Parodi Amaya

LSU Doctoral Dissertations

The work presented here has 3 goals: establish the need for novel neurostimulation waveform solutions through a literature review, develop a neurostimulation pulse generator, and verify the operation of the device for neurostimulation applications.

The literature review discusses the importance of stimulation waveforms on the outcomes of neurostimulation, and proposes new directions for neurostimulation research that would help in improving the reproducibility and comparability between studies.

The pulse generator circuit is then described that generates signals inspired by the shape of excitatory or inhibitory post-synaptic potentials (EPSP, IPSP). The circuit analytical equations are presented, and the effects of the circuit …

The Use Of Geospatial Modeling And Novel Diagnostics To Detect And Map Risk Factors Of Soil-Transmitted Helminths In Feira De Santana, Brazil, Ryan Harry Avery

LSU Doctoral Dissertations

Soil-transmitted helminth (STH) infections impact billions of people worldwide. The traditional STH control approach is a morbidity control strategy implementing mass drug administration (MDA) programs targeting school-aged children (SAC). In Brazil, this control strategy has decreased STH prevalence to less than 20% in most of the country and providing an opportunity to transition from the morbidity control program and towards a surveillance and response system geared towards STH elimination. Surveillance and response systems geared towards elimination require the implementation higher accuracy diagnostics to detect infection in low-transmission communities, surveillance of entire households, high-resolution modeling at the household-habitat scale, and targeted …

Can Assisted Reproductive Technologies Help Conserve 300 Million Years Of Evolution? A First Attempt At Developing These Technologies For Male Reptiles, Sean M. Perry

LSU Doctoral Dissertations

Biodiversity loss is the most critical environmental problem threatening ecosystem, animal, and human health today. Increases in extinction rates have been observed over the past 50 years, with reptile losses occurring twelve times faster than traditional extinction rates. This demonstrated biodiversity loss is secondary to climate change, habitat destruction, infectious disease, invasive species, poaching, and unsustainable trade. Approximately 20% of all reptiles are threatened with extinction and population declines are approaching rates similar to the current amphibian extinction crisis. Preventing the extinction of reptiles will require humans to acknowledge these losses and develop plans to preserve these evolutionary sentinel species. …

Evaluation Of Oncolytic And Immunomodulatory Potential Of The Hsv-1 Live-Attenuated Vaccine Strain Vc2 In An Immunocompetent Murine Melanoma Model, Natalie Wall Fowlkes

LSU Doctoral Dissertations

Melanoma accounts for 90% of skin cancer-related deaths in humans. Treatment options for metastatic melanoma in people is very limited. Melanoma is considered to be an immunogenic tumor, spurring interest in development of immunotherapies for the treatment of metastatic melanoma. Oncolytic virotherapy has been widely investigated. The first ever oncolytic virotherapy to receive FDA-approval is an HSV-1-based virus (Talimogene Laherperavec (T-Vec) or Imlygic) containing a transgene for human GM-CSF to enhance anti-tumor immune responses after injection. Durable response rate in human patients was only 16% despite impressive efficacy in anti-tumor effects in vitro and in murine tumor models. Novel viruses …

The Effects Of Chemical Reagents And Physical Environment On The In Vitro And In Vivo Properties Of Adipose-Derived Multipotent Stromal Cells Isolated From Different Species, Wei Duan

LSU Doctoral Dissertations

Adult adipose derived mesenchymal stromal cells (ASCs) have been characterized in various species. Many factors may affect ASC fate and ASCs from different species may have different response to these factors. The first study was to identify the differences of the canine ASCs isolated from subcutaneous and infrapatellar adipose tissues, and evaluate the impact of cryopreservation on the cells. Based on paired comparisons of fresh and cryopreserved ASCs, cryopreserved ASCs had lower CD29 and CD44 protein expression and lower proliferation rates. The cryopreserved ASCs had relative lower mitochondria in the cytoplasm compared to the fresh ASCs regardless of tissue sources. …

Chikungunya Virus Infection-Associated Bone And Joint Disease, Brad A. Goupil

LSU Doctoral Dissertations

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that circulates predominantly in tropical and subtropical regions. Infection results in severe debilitating polyarthralgia during the acute phase of disease, and reports suggest that chronic arthralgia lasting months to years after the initial infection can occur. More severe and prolonged disease has been associated with pre-existing joint disease, though this has not been experimentally examined. In the research presented herein, two established mouse models (adult IRF 3/7 -/- -/- and wild-type C57BL/6J mice) were utilized to characterize CHIKV-associated bone and joint disease and evaluate its impact on the progression of pre-existing osteoarthritis (OA) …

The Ability Of Bull And Stallion Thawed Spermatozoa Refrozen Without Cryoprotectants To Activate Intra- And Interspecies Oocytes, Jose Len Yin

LSU Doctoral Dissertations

Semen cryopreservation has allowed the establishment of genome banks and the large scale propagation of species. The development of simple techniques to cryopreserve semen or alternatives to efficiently use cryopreserved semen from males of valuable genetics that have become infertile will permit continuous propagation of the genetics from these males and may serve as a model for preservation and propagation of endangered species. Sperm cryopreservation without cryoprotectants is a simple process, and offspring have been produced following intracytoplasmic sperm injection (ICSI); however the ability of frozen-thawed sperm refrozen without the addition of cryoprotectants to activate oocytes following ICSI was unknown. …

Rickettsia Felis, Transmission Mechanisms Of An Emerging Flea-Borne Rickettsiosis, Lisa Diane Brown

LSU Doctoral Dissertations

Rickettsia felis is an emerging insect-borne rickettsial pathogen and the causative agent of flea-borne spotted fever. First described as a human pathogen from the United States in 1991, R. felis is now identified throughout the world and considered a common cause of fever in Africa. The cosmopolitan distribution of this pathogen is credited to the equally widespread occurrence of cat fleas (Ctenocephalides felis), the primary vector and reservoir of R. felis. Additionally, R. felis has been identified in other hematophagous arthropods (including numerous species of fleas, ticks, mosquitoes, and mites). Most transmission cycles of pathogenic Rickettsia include transovarial and transstadial …

Identification And Characterization Of A Relish-Type Nf-Kb, Dvrelish In Dermacentor Variabilis, The American Dog Tick, Victoria Irene Verhoeve

LSU Doctoral Dissertations

Ticks are important worldwide as vectors of bacteria, viruses, and parasites. Pathogenic and non-pathogenic Spotted fever group (SFG) Rickettsia are maintained and transmitted by ticks with specific hard tick-Rickettsia pairings evident in nature. The pathogenic SFG Rickettsia rickettsii is transmitted by the hard tick Dermacentor variabilis. In response to infection, D. variabilis is known differentially respond to SFG Rickettsia infection. The mechanisms of differential immune induction are currently unknown, and are likely involved in the establishment of specific tick-SFG Rickettsia pairings. It was hypothesized that the level of response by D. variabilis to SFG Rickettsia occurs in a species-specific manner, …

Characterization Of Rickettsial Infection Dynamics Within Dermacentor Variabilis And Amblyomma Maculatum, Emma Kate Harris

LSU Doctoral Dissertations

Spotted fever group (SFG) Rickettsia are primarily associated with their reservoir host and vector, the tick. Rickettsial colonization and maintenance within the arthropod is a key component of vector competence and pathogen transmission to the mammalian host. Contemporary detection of novel tick hosts for rickettsial species, combined with an unprecedented rise in human cases of SFG rickettsiosis, necessitates a deeper understanding of tick/Rickettsia interactions. The hypothesis for this work is that if primary tick/Rickettsia pairings do not exist then rickettsial determinants account for primary vector/pathogen relationships. To this end, Dermacentor variabilis and Amblyomma maculatum ticks were exposed to R. rickettsii, …

Amblyomma Maculatum Immunomodulation In Mammalian Models Of Rickettsia Parkeri Rickettsiosis, Kaikhushroo Hormazd Banajee

LSU Doctoral Dissertations

Rickettsia parkeri is an emerging human pathogen and spotted fever group Rickettsia that is transmitted via Amblyomma maculatum (the Gulf Coast tick) in the United States. Since these ticks must feed for several days in order to molt to the next life cycle, they must be able to counteract the host immune response. Despite this fact, there have been few studies that evaluate the immunomodulatory effect of this vector and the resultant influence on rickettsial disease. The hypothesis of this research is that, if A. maculatum feeding modifies the host immune response, this immunomodulation will enhance disease caused by R. …

The Role Of Herpes Simplex Virus Type 1 Glycoprotein K In Neuroinvasion And Immunopathogenesis Of Herpes Keratitis, Ahmad Saied

LSU Doctoral Dissertations

ABSTRACT Herpes simplex virus type 1 is a common neurotropic pathogen responsible for a multitude of human diseases ranging from mucocutaneous lesions, keratitis to life-threatening encephalitis. The hallmark of the HSV-1 life cycle is infection of sensory neurons, where the virus establishes a latent infection for the life of the host. Viral envelope glycoproteins play important roles in viral life cycle and virus-host interaction. Viral glycoproteins gK, gM, gE and the membrane protein UL11 have been shown to be important for virus assembly, egress and virus spread. To investigate the relative importance of each of gK, gM, gE and UL11 …

The Use Of Geographic Information Systems And Ecological Niche Modeling To Map Transmission Risk For Visceral Leishmaniasis In Bahia, Brazil, Moara De Santana Martins

LSU Doctoral Dissertations

Leishmaniasis is a public health problem in Brazil, and despite the control programs in place, Bahia remains one of the states with the highest incidence rates of cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL). This study proposed to develop and evaluate the applicability of ecological niche models (ENM) for leishmaniasis, to determine the influence of environmental and socioeconomic factors on the incidence of these diseases at three geographic scales: national, statewide and community. Water availability, garbage collection, precipitation and temperature were the most important variables in predicting areas suitable for VL and CL in the country. The extensive geography of …

Comparative Genomic Studies Of Catfish And Zebrafish Strains Of Edwardsiella Ictaluri, Rui Wang

LSU Doctoral Dissertations

Edwardsiella ictaluri is a gram negative bacterium that is the causative agent of enteric septicemia of catfish. In 2011, this bacterium was identified as the causative agent of massive death in zebrafish populations in U.S. In this project, we found that isolates of E. ictaluri from zebrafish comprise a unique strain that differs from the type strain of E. ictaluri phenotypically as well as genetically. Also, strains of E. ictaluri from zebrafish are non-infectious in channel catfish Ictalurus punctatus by immersion. Here we sequenced the zebrafish strains of E. ictaluri LADL11-100 and LADL11-194 and compared the potential virulence genes in …

Development And Characterization Of A Live-Attenuated Vaccine To Combat Equine Herpesvirus Type-1 Infections, Shiliang Anthony Liu

LSU Doctoral Dissertations

Equine Herpesvirus 1 (EHV-1) is an important ubiquitous enzootic equine pathogen and one of the most common pathogens of the horse, causing, respiratory disease, epidemic abortion, occasionally neurological disease in horses, which leads to significant economic losses to the horse industry. EHV-1 induces several clinical signs of disease ranging in severity, from mild respiratory disease to abortion in pregnant mares, neonatal foal death and neuropathogenic disorders. Natural EHV-1 infection stimulated short lived protective immunity and had both humoral and cellular immune responses. Currently vaccination remains the best option to prevent EHV-1 infection and different applications of vaccination have been investigated …

Influence Of Aedes Aegypti Saliva On The Vertebrate Host Response To Dengue Virus, Michael Kevin Mccracken

LSU Doctoral Dissertations

Dengue virus (DENV) is maintained in a primarily anthroponotic cycle between humans and the mosquito, Aedes aegypti. Investigations into DENV infection of the vertebrate host generally do not account for the contribution of vector saliva, an inherent part of the mosquito-borne viral inoculum. Feeding by mosquitoes on vertebrate hosts is initiated by probing, which results in physical damage to the skin and vasculature, and the simultaneous introduction of DENV and saliva into the skin. Saliva contains many individual proteins with the potential to modulate host hemostasis and immune responses, thereby facilitating blood feeding and virus transmission. As exogenous antigens, both …

The Role Of Viral Glycoproteins And Tegument Proteins In Herpes Simplex Virus Type 1 Cytoplasmic Virion Envelopment, Dmitry Vladimirovich Chouljenko

LSU Doctoral Dissertations

Herpes simplex virus type 1 (HSV-1) is a ubiquitous neurotropic alphaherpesvirus transmitted by contact with mucocutaneous surfaces of infected individuals. HSV-1 enters the host by fusion of the viral envelope with the host cell plasma membrane, followed by translocation of the viral capsids to the nucleus where viral DNA is injected into the host cell nucleus to initiate viral replication. To generate infectious virions, newly assembled capsids travel to the cytoplasm and undergo a process called secondary envelopment by budding into cytoplasmic vesicles derived from the trans-Golgi network. Cytoplasmic envelopment is a complex process involving interactions between a multitude of …

Genetics And Functions Of Herpes Simplex Virus Type-1 Membrane Proteins Ul20/Gk In Virion Envelopment And Entry, Anu Susan Charles

LSU Doctoral Dissertations

The envelopment and egress of the Herpes Simplex Virus is an important event in the life cycle of the virus. The important membrane proteins required for the envelopment and egress of the virus are glycoproteins gM, gK, gE and non-glycosylated membrane proteins UL20p and UL11. Among them one of the most critical protein is the UL20 protein which has four transmembrane domains with amino and carboxyl termini are predicted to lie within the cytoplasmic side of cellular membranes. Studies done in our laboratory have shown that deletion of UL20 or other lethal mutations have an adverse effect on envelopment and …

Comparison Of Immune Responses During Gastrointestinal Helminth Self-Cure Expulsion Between Resistant Gulf Coast Native And Susceptible Suffolk Sheep, Javier Jesus Garza

LSU Doctoral Dissertations

The immune response to the self-cure phenomenon seen during gastrointestinal nematode (GIN) parasitism of small ruminants was compared between sheep breeds that are resistant or susceptible to Haemonchus contortus infection. Fifty-four Gulf Coast Native (resistant) and Suffolk (susceptible) lambs were allowed to acquire a natural GIN infection on pasture and were then randomly allocated into 4 groups. After being moved to parasite free housing for 2 months, lambs were given a challenge infection of 20,000 H. contortus L3. Fecal egg counts (FEC) were monitored throughout the study and animals were necropsied at 0, 1, 3, and 7 days post infection …

Outer Surface Lipoprotein Layer Homeostasis And Gene Regulation In Borrelia Burgdorferi, Poonam Dadhwal

LSU Doctoral Dissertations

The outer surface lipoprotein (osp) layer forms an interface between the internal and the external environment of the Lyme disease spirochete, Borrelia burgdorferi. The homeostatic maintenance of the osp layer effectuates adaptation of B. burgdorferi as it gets transmitted from the tick vector to a mammalian host and vice-versa. However, the regulation of the outer surface lipoproteins (osps) is still a conundrum for borrelia scientists. Part of this dissertation inquires about the homeostatic maintenance of the osp layer. We found that the deletion of the dominantly expressed tick phase osp, OspA, induces expression of two other osps. OspD, and BBJ41. …

Mechanisms Of Innate Immunity In Polymicrobial Sepsis, Liliang Jin

LSU Doctoral Dissertations

Severe bacterial sepsis leads to a pro-inflammatory condition that can manifest as septic shock, multiple organ failure, and death. Neutrophils are critical for the rapid elimination of bacteria, however, the role of neutrophil chemoattractant CXCL1, pattern recognition receptors (PRRs)- NLR protein 3 (NLRP3) and alcohol in bacterial clearance during sepsis remains elusive. We demonstrate that CXCL1 plays a pivotal role in mediating host defense to polymicrobial sepsis following cecal ligation and puncture (CLP) in gene-deficient mice. CXCL1 appears to be essential for restricting bacterial outgrowth and preventing multiple organ failure and death in mice. Moreover, CXCL1 is essential for neutrophil …