Veterinary Medicine Commons^™

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 …

In Vitro Analysis Of Equine Platelet Rich Plasma And In Vivo Effect Of Cytokines After Repeated Intra-Articular Injections In Osteoarthritic Joints, Carlos Aguilar Miranda

LSU Master's Theses

INTRODUCTION- The use of biologic therapies like platelet rich plasma (PRP) has a potential benefit for the treatment of osteoarthritis in horses. However, key parts of it are still unknown. The objective is to evaluate the degree of platelet activation achieved when in contact with exogenous activators. As well as the long-term effect in the anabolism and catabolism of cytokines involved in equine osteoarthritis.

MATERIAL AND METHODS-In one in vitro study PRP was collected from 6-horses using a commercially available kit. Platelets were exposed to PBS as negative control or to varying concentrations of CaCl2. Activation was determined via cell …

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 …

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. …

Evaluation Of Plasma Sprayed Hydroxyapatite Coated Ao Cortical Screws In Equine Third Metacarpal Bone, Myra Elizabeth Durham

LSU Master's Theses

ABSTRACT Objectives - To compare the osteointegration of plasma sprayed hydroxyapatite (HA) coated and uncoated 5.5 mm cortical screws in equine third metacarpal (MC3) bones in combination with a 4.5mm broad dynamic compression plate (DCP). Study design - In vivo study. Animals – 6 Adult Thoroughbred horses. Methods – For each horse, four HA coated screws were placed unicortically through a 4.5mm broad DCP in the dorsal cortex of a randomly chosen MC3 bone, with 4 uncoated screws placed in an identical manner in the contralateral MC3 bone. All screws were tightened to a torque of 5.4 N-m. Extraction torques …

The Effects Of Iodixanol Present During Equine Semen Cryopreservation, David Paul Beehan

LSU Master's Theses

The objectives of this study were to determine what effects iodixanol would have on total and progressive motility, plasma membrane integrity (viability), acrosome integrity and DNA structure when present during cryopreservation of equine spermatozoa,. We hypothesized that the addition of iodixanol would improve post-thaw values for measured parameters. Ejaculates from six stallions were collected, centrifuged at 900 x g for ten minutes to remove supernatant, and suspended to 200 x 106 cells/ml with 0%, 2.5% and 5% iodixanol in an egg-yolk based extender and cryopreserved. Before and after cryopreservation sperm motility was assessed by computer assisted semen analysis, and samples …

Isolation And Characterization Of Adult Progenitor Cells From Healthy And Laminitic Hoof Tissue, Vanessa Pinto

LSU Master's Theses

Laminitis is an often fatal condition in horses with few available and only moderately effective treatment options. Separation of laminar dermis and epidermis lead to rotation or ventral deviation of the third phalanx inside the hoof capsule. Despite being a modified skin, equine laminar tissue does not completely return to normal after laminitis. The hypothesis tested was that adult progenitor cells in the equine laminar tissue are irreversibly damaged by laminitis. A method to harvest and culture cells in vitro from the equine lamina was established; and progenitor cells from unaffected and laminitic hooves were characterized and compared. Laminar tissue …

Mechanical Evaluation Of Aluminum Oxide Roughened Screws In Equine Third Metacarpal Bone, Petrisor Baia

LSU Master's Theses

ABSTRACT Objectives – To compare the osseointegration of roughened and electropolished 5.5 mm cortical screws used to secure a 4.5 mm broad dynamic compression plate (DCP) in equine third metacarpal (MC3) bones. Study Design – In vivo study Animals – 5 Adult thoroughbred horses (2-7 years old). Methods – For each horse one MC3 was randomly assigned to secure a 4.5 mm broad DCP with 4aluminum oxide (Al2O3) roughened screws on the dorsal mid diaphysis. Four regular electropolished screws used to secure a similar plate on the contralateral limb served as control. They were removed at 12 weeks and the …

Antiviral Chemotherapeutic Agents Against Equine Herpesvirus Type 1: The Mechanism Of Antiviral Effects Of Porphyrin Derivatives, Galena V. Rybachuk

LSU Doctoral Dissertations

Equine Herpesvirus-1 (EHV-1) is an important ubiquitous enzootic equine pathogen, causing significant economic losses to the horse industry. Despite extensive vaccination protocols, EHV-1 continues to be a major cause of epidemic abortion, perinatal mortality, respiratory disease and neurologic disease. EHV-1 infections are usually dealt with by using management practices that limit spread of the disease and secondary complications, providing symptomatic relief to infected horses, but no specific treatment is available. New therapeutic or virucidal agents could have great utility in slowing both the progression and spread of the disease in an epidemic situation. A number of porphyrins and their derivatives …

Matrix Metalloproteinases In The Equine Systemic Inflammatory Response: Implications For Equine Laminitis, Lee Ann Fugler

LSU Doctoral Dissertations

Laminitis is a crippling and often life-threatening disease of the equine foot. Soft tissue damage characteristic of this disease has been associated with increased MMP activity. Therefore, it seems likely that MMPIs could be potential therapeutic agents for laminitis. Further characterization of equine MMPs and evaluation of the effectiveness of MMPIs in the horse are needed. Equine MMP-9 was harvested from neutrophils, purified by affinity chromatography, and evaluated using western blotting and gelatin zymography. The Biotrak MMP-9 Activity Assay was evaluated for use with equine samples using equine neutrophil MMP-9 as a standard, and was determined to have insufficient sensitivity …

The Effects Of Non-Focused Extracorporeal Shock Waves On Neuronal Morphology, Function And Analgesia In Horses, David Manuel Bolt

LSU Master's Theses

These studies were conducted to elucidate the regional analgesic effect that is observed clinically after treatment of orthopedic disorders with application of extracorporeal shock waves in horses. Regional analgesia after treatment with extracorporeal shock waves presents a concern because it may eliminate protective limiting mechanisms and may place equine athletes with predisposing lesions at risk of sustaining career- or life-ending injuries. Direct percutaneous application of non-focused extracorporeal shock waves to palmar digital nerves in the pastern area of horses resulted in decreased sensory nerve conduction velocities compared with untreated control nerves at 3, 7, and 35 days after treatment. Transmission …

Equine Immunity To Cyathostome Infections, Marie Alexandra Baudena

LSU Doctoral Dissertations

To study the protective responses of cyathostome-infected ponies, two challenges were performed employing animals with different histories of exposure to these parasites. The hypothesis developed and to be tested in these experiments was that ponies that had longer exposure to cyathostome contaminated pastures would express acquired resistance to infection. The assumption behind this hypothesis was that helminth-naïve ponies infected with cyathostomes would eliminate the infection using only innate immune responses. Whereas previously exposed ponies would eliminate the infection with acquired immune responses, and these would be more effective in ponies with longer exposure to cyathostomes. Thus, helminth-naïve animals would acquire …

The Effects Of Intra-Articular Silicone Polymer On Synovial Fluid, Synovial Tissue, And Articular Cartilage In The Equine Middle Carpal Joint, Marilyn Rumbaugh

LSU Master's Theses

There is anecdotal documentation that intra-articular administration of liquid silicone is used as a lubricant for equine joints. Effects of silicone polymer on equine articular cartilage and synovial fluid have not been evaluated. The objectives were to characterize the effects of intra-articular administration of liquid silicone polymer on clinical, synovial fluid, and microscopic features in normal middle carpal joints of horses, and to determine if silicone migrates to the axillary lymph nodes. Eight adult horses were used in this study. Two mLs of 1,000 centistoke, medical-grade silicone was injected into one randomly selected middle carpal joint. The opposite middle carpal …

Role Of Endothelin In The Pathogenesis Of Acute Laminitis In Horses, Ashley Michelle Stokes

LSU Doctoral Dissertations

Acute laminitis is a severely debilitating disease of the laminae of the equine digit; however, the mechanism(s) of pathogenesis have yet to be fully elucidated. In physiologic states, the endothelium synthesizes substances, such as nitric oxide (NO; vasodilator) and endothelin-1 (ET-1; profound vasoconstrictor), which play a crucial role in vasomotor regulation. The overall hypothesis is that the initiating factor in the onset of acute laminitis is a disruption in the balance between NO and ET-1, which leads to digital vasoconstriction and subsequent laminar ischemic necrosis. In vitro studies with digital vessels from healthy horses and horses with naturally-acquired laminitis determined …