Large or Food Animal and Equine Medicine Commons^™

Maternal Hyperleptinemia Alters Placental Transcriptome And Progesterone Regulation Without Affecting Early Equine Fetal Growth, Lucinda L. Thorburn

LSU Master's Theses

While consequences of equine obesity are well defined, the extent to which persistent hyperleptinemia and accompanying leptin (Lep) resistance affect the fetal-maternal environment warrants further exploration. This study compared endocrine, fetal, placental, and uterine parameters during early pregnancy (through day 70) in mares with elevated leptin versus normal leptin (NL) concentrations. Fourteen mares were classified as either NL (n = 6; Lep 0.9 ± 0.3 ng/mL), moderate leptin (ML; n = 4; Lep 3.0 ± 0.3 ng/mL), or high leptin (HL; n = 4; Lep 5.8 ± 0.7 ng/mL) based on annual plasma leptin. Mares were artificially inseminated and induced …

Gastrointestinal Ischemia In The Horse: Preoperative Detection And Surgical Intervention, Michael P. St. Blanc

LSU Master's Theses

The objective of this study was to evaluate the utility of calprotectin, a protein released by activated leukocytes during inflammation, in the detection of gastrointestinal ischemia in horses with signs of abdominal pain (colic). Additionally, one-layer end-to-end anastomoses of the descending colon were critically evaluated in comparison to two-layer closures. For the calprotectin portion of the study, samples were obtained from ten control horses and nineteen clinical cases assigned to three treatment groups (non-strangulating, strangulating small intestinal, or strangulating large intestinal lesions). Objective data was collected from each patient, and calprotectin concentration in serum and peritoneal fluid was determined using …

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 …

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 …

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 …

Intra-Articular Buprenorphine In Horses, Gabriel Castro-Cuellar Dr

LSU Master's Theses

Opioid drugs have the potential of provide local analgesia in inflamed joints. To date, morphine is the only opioid that has been tested for intra-articular (IA) administration in horses. Having an alternative drug, other than morphine, could widen the therapeutic options, particularly in cases of drug shortages or inaccessibility to specific drugs. The work presented in this dissertation reports the cytotoxic effects of buprenorphine on cultured equine chondrocytes, and the pharmacokinetic, pharmacodynamic and analgesic effects, of IA administered buprenorphine in horses with experimentally induced synovitis.

To evaluate the potential cytotoxic effects on equine cartilage, chondrocytes were obtained from normal equine …

Biomechanical Comparisons Of Metacarpophalangeal Joint Arthrodesis Techniques In The Horse, Lawrence Ivan M. Kadic

LSU Master's Theses

INTRODUCTION - Break down injuries resulting in the disruption of the suspensory apparatus, or the development of moderate to severe osteoarthritis of the metacarpophalangeal (MCP) and/or metatarsophalangeal (MTP) joint, are well documented reasons to perform a surgical arthrodesis in horses. The objective of this thesis was to compare the biomechanical characteristics of different arthrodesis techniques for the equine MCP joint.

MATERIALS AND METHODS - The first cadaveric study evaluated the biomechanical properties of two constructs with 5.5 mm broad 10-hole LCP alone or in combination with a 2.0 mm stainless-steel cable under cyclic fatigue testing and single cycle to failure …

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 …

Potential Role Of Acetylation On Equine Sperm Capacitation, Luis H. De Aguiar

LSU Master's Theses

A series of biochemical and physical modifications in the sperm during the transport in the female reproductive tract that make the sperm capable of fertilization are called capacitation. It is an important process since ejaculated sperm is not capable of fertilizing an oocyte before capacitation. The sperm modifications during the capacitation process include changes in membrane fluidity, tyrosine phosphorylation, calcium influx, pH increase and hyperpolarization, leading the sperm to achieve hypermotility and the acrosome reaction, which are also required for conventional in vitrofertilization (IVF). In vitro production of embryos leading to viable offspring has been successful in different …

Development Of A Perineural Injection Of The Caudal Cervical Spinal Nerve Roots In Horses, Jonuel A. Cruz-Sanabria

LSU Master's Theses

Neck pain in horses can result in lameness and poor performance and can occur from arthritis of cervical articular process joints (APJs). Current treatment consists of direct injection of corticosteroids into the cervical APJs; however, this does not alleviate pain in all horses. New bone formation around the APJ can also result in compression of the spinal nerve roots and pain. The purpose of this study was to develop an ultrasound-guided cervical perineural injection technique and assess the safety of performing the technique in normal healthy horses. An ultrasound-guided cervical perineural injection technique of the caudal cervical spinal nerve roots …

An Evaluation Of Pathophysiology And Biomechanics Of Selected Lamenesses In The Horse, Cole Barrett Sandow

LSU Master's Theses

INTRODUCTION-Laminitis and synovitis are two common causes of equine lameness. Laminitis is most often associated with hyperinsulinemia and osteoarthritis is most commonly the result of synovitis. The objective is to evaluate biomechanical and pathophysiologic events regarding laminitis and synovitis.

MATERIALS AND METHODS-The first study evaluated biomechanical effects of insulin on lamellar strength. For this experiment, lamellar explants were harvested, incubated in media only (serving as a control) or media with a high concentration of insulin for 8 hours. After incubation, structural integrity was evaluated with a mechanical testing device. Data included load to failure (N), stress to failure (MPa), elongation …