Veterinary Medicine Commons^™

Evaluating Viability, Developmental Competence, And Chromatin Configurations Of Cryopreserved Equine Oocytes, Tricia Adams

LSU Doctoral Dissertations

Assisted reproduction technology and the use of specialized laboratories have increased in the horse breeding industry over the last decade. This expansion has highlighted the inability to routinely cryopreserve oocytes and preserve female genetics. Oocyte vitrification, a cryopreservation process, continues to be characterized as an experimental procedure in horses. The goal of this dissertation was to evaluate the viability, developmental competence, and nuclear structures of cryopreserved equine oocytes to illuminate potential areas of improvement in the vitrification process. Oocytes were collected from abattoir derived ovaries and exposed to either varying lengths of in vitro maturation (IVM) or pretreated with a …

Canine Hepatocellular Carcinoma: Evaluating Pgam5 And Heterobilharzia Americana, Priscilla Devora

LSU Doctoral Dissertations

Hepatocellular carcinoma (HCC) is the most common primary liver cancer in humans and domestic dogs. Despite extensive research, the mechanisms that drive HCC carcinogenesis and perpetuate cancer survival are incompletely understood in both species. The work described herein focused on finding similarities between canine and human HCC, which could be harnessed to benefit humans and dogs with cancer. The first aim was to investigate the expression of phosphoglycerate mutase 5 (PGAM5) in canine HCC. Upregulation of PGAM5 is a negative prognostic indicator in human HCC. Using archival formalin-fixed paraffin-embedded samples, we found that PGAM5 was overexpressed in canine HCC ( …

The Hoof Inside Out: A Comprehensive Investigation About The Shoe Configuration Effects On The Behavior Of The Equine Hoof, Rita Aoun

LSU Doctoral Dissertations

The equine hoof is a unique organ in biology that has intricate elastic properties. From simple protection to therapeutic and corrective measures, horseshoes are widely used in the equine industry. Various types of shoeing have been designed and used based on their unique targeted functions following hoof care. Shoes can modify the gait of the horse, affect the alignment of the distal joints, and alter stress and strains on specific hoof regions. The objective of this dissertation is to provide an overview of the available research on the existing methodology and literature on the effects of shoeing on equine gait …

Characterizing The Roles Of Bacterial And Viral Agents In House Crickets (Acheta Domesticus) At Commercial Rearing Facilities In The United States, Kimberly L. Boykin

LSU Doctoral Dissertations

Feeder insects, and in particular crickets, are becoming more popular as food for humans and domesticated animals. However, disease outbreaks continue to decimate commercial populations. The goals of this dissertation were to characterize the epidemiology of different viral and bacterial pathogens affecting the survival of European house crickets (Acheta domesticus) being raised under mass rearing conditions and identify methods to reduce the impact of these pathogens.

Crickets from nine different producers across the United States were sampled during different seasons to better estimate the prevalence of three pathogenic viruses: Acheta domesticus densovirus (AdDV), Acheta domesticus volvovirus (AdVVV), and …

Investigations Of Emerging Zoonotic And Vector-Borne Viruses At The Juncture Of Environmental, Human, And Animal Health, Erik A. Turner

LSU Doctoral Dissertations

Reemerging and emerging zoonotic viruses are some of the most important public and One Health threats facing the world. Understanding the transmission dynamics of these viruses is vital to reducing the disease burden, and one of the key aspects to these transmission systems is the environmental vertex of the One Health triangle. SARS-CoV-2 has only recently emerged as a global public health threat, and within 4 years, over 700 million cases have been reported. As a novel pathogen, many aspects of transmission, including environmental fomite transmission and disinfection, were initially a glaring gap in knowledge. Additionally, while chikungunya virus (CHIKV) …

The Pathophysiology Of Equine Glandular Gastric Disease: Investigating The Role Of The Mucosal Microbiome And Bile Acid Reflux, Linda Paul

LSU Doctoral Dissertations

Equine glandular gastric disease (EGGD) is a common disease of athletic horses that can affect performance and welfare. Clinical signs are non-specific and diagnosis is made using gastroscopy after a prolonged fasting period. Effective prevention and treatment strategies for EGGD are lacking despite its widespread prevalence and negative effects. The goal of this research was to investigate the pathophysiology of EGGD. Objectives included: 1) compare the gastric glandular mucosal microbiome in horses with and without EGGD, 2) assess the influence of dietary and management factors on the gastric microbiome, and 3) evaluate the pyloric gastric fluid bile acid profile in …

Predicted Structure And Functional Roles Of Alphaherpesvirus Tegument Protein Ul37 In Virion Morphogenesis And Innate Immunity, Therese Marie Collantes

LSU Doctoral Dissertations

Several members of the Family Herpesviridae are clinically significant pathogens, affecting humans and a wide range of animals. Alphaherpesviruses infect epithelial cells at the primary site of infection and subsequently invade adjacent sensory neurons. Infectious bovine rhinotracheitis (IBR) is an economically important disease caused by bovine herpesvirus 1 (BoHV-1), which belongs to the subfamily Alphaherpesvirinae, genus Varicellovirus. To date, vaccination is the only preventive measure against IBR. Understanding determinants of herpesvirus replication and innate immune regulation is important to help further develop vaccines that are efficacious and incapable of establishing latency in the host nervous system. The alphaherpesvirus …

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 …

Cell-Specific Role Of Il4rα Signaling In Allergic Asthma, Ishita Choudhary

LSU Doctoral Dissertations

IL-4 and IL-13 play a critical role in allergic asthma pathogenesis via their common receptor, i.e., interleukin 4 receptor alpha (IL4Rα). However, the cell type-specific role of IL4Rα-mediated signaling in allergic asthma has remained unclear. We hypothesized that the role of IL4Rα signaling in allergic asthma is cell-type specific. To test our hypothesis, we challenged myeloid cell-specific IL4Rα-deficient (LysMcre^+/+/IL4Rα^fl/fl), myeloid cell-specific IL4Rα-sufficient (LysMcre^+/+/IL4Rα^wt/wt), airway epithelial cell-specific IL4Rα-deficient (CCSP-Cre⁺/IL4Rα^fl/fl), and airway epithelial cell-specific IL4Rα-sufficient (CCSP-Cre^-/IL4Rα^fl/fl) mice with either mixed allergens (MA) or normal saline three …

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 …

The Role Of Kisspeptins In Trophoblast Cell Dynamics: Comparative Studies Using The Horse And The Preeclamptic-Like Bph/5 Mouse As Animal Models, Viviane Cristine Leite Gomes

LSU Doctoral Dissertations

Kisspeptins, a family of small peptides derived from the Kiss1 gene, have been described in trophoblast cell dynamics, placentation, and pregnancy outcomes. Furthermore, many other physiological functions have been attributed to kisspeptins, including neuroendocrine regulation of puberty and cyclicity, and peripheral and central regulation of metabolism and adipogenesis. Herein, studies were performed in the Blood Pressure High Subline 5 (BPH/5) mouse and the horse to further investigate the role of kisspeptins in pregnancy. The BPH/5 mouse recapitulates the main features of human preeclampsia (PE), a hypertensive disorder of pregnancy associated with maternal and fetal adverse outcomes. BPH/5 phenotypic characteristics include …

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 …

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 …

Investigation Of Bovine Herpesvirus-1 Determinants Of Neuronal Infectivity In Novel Bovine Neuronal Cell Systems For Development Of A Safer Viral Vaccine Vector, Jared Rudd

LSU Doctoral Dissertations

Bovine herpesvirus-1 (BoHV-1) is the causative agent of infectious bovine rhinotracheitis and a component of the bovine respiratory disease complex. BoHV-1 is a significant burden on the cattle industry in the United States causing severe respiratory disease, abortions, loss of calves (“shipping fever”). BoHV-1 belongs to the alphaherpesvirus subfamily of Herpesviridae. Alphaherpesviruses enter axons of sensory nerves and establish life-long latency in trigeminal and dorsal root ganglionic neurons after primary infection of the oronasal or genital epithelium respectively. Modified live attenuated vaccines for BoHV-1 are commercially available but are limited in their protection while retaining the ability to establish latency …

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 …

Hsv-1 Live-Attenuated Vaccine Strain Vc2 Confers Complete Protection In Mice Against Ocular Immunipathogenesis By The Human Clinical Strain Hsv-1 (Mckrae), Shan Krishnan Naidu

LSU Doctoral Dissertations

Herpes simplex virus type-1 (HSV-1) can cause severe ocular infection and blindness. We have previously shown that the HSV-1 VC2 vaccine strain is protective in mice and guinea pigs against genital herpes infection following vaginal challenge with HSV-1 or HSV-2. In this study, we evaluated the efficacy of VC2 intramuscular vaccination in mice against herpetic keratitis following ocular challenge with the lethal human clinical strain HSV-1(McKrae). VC2 vaccination in mice produced superior protection and morbidity control in comparison to its parental strain HSV-1(F). Specifically, after HSV-1(McKrae) ocular challenge, all VC2- vaccinated mice survived, while 30% of the HSV-1(F)- vaccinated and …

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. …

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, …

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. …