Muscle glycogen metabolism in horses

TREATMENT OF FLEXURAL DEFORMITIES

THE ROLE OF VOLATILE FATTY ACIDS IN EQUINE GASTRIC ULCERS In recent years, the prevalence of gastric ulcers in athletic horses has become widely recognized. In previous work funded by GJCF, the role of several types of acids, as well as low pH, were demonstrated to be important factors in producing gastric ulcers in horses fed high concentrate diets. The next step, via this project, is to determine effects of different concentrations of acids on stomach injury, and also to determine if calcium can protect the stomach against this type of condition. Dr. Frank Andrews University of Tennessee

DEVELOPMENT OF A REFINED EQUINE MODEL FOR EPM EPM research has been hampered by the inability to reproduce the disease in horses to create a model for study. As knowledge about EPM continues, a recent development by this research team is indication that stress of transportation within close time proximity to infection created more severe clinical cases than when the infection was dissociated from travel. The purpose of this study is to refine the equine model by determining the amount of the protozoan infection required to produce severe clinical symptoms in relationship to transport. EPM is widely regarded as the most important neurologic disease in the horse today. Dr. William Saville Ohio State University

BASIS FOR THE

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Contraction of tendons in foals produces “over-flexion” of the limbs, a common and potentially devastating problem. While splinting, bandaging, and controlled exercise have been used in mild cases of limb deformity, surgery is often required. However, surgery alone is not always successful in metacarpal phalangeal deformities and is not an option in many rear limb flexural deformities. Large doses of the intravenous antibiotic oxytetracycline have produced successful results in addressing mild to moderate deformities in foals. However, the mechanism by which oxytetracycline prompts correction is unknown; moreover, dosages routinely used in this way have been shown to induce kidney failure in some cases. This project will test the premise that the oxytetracycline inhibits the contractile mechanism in a dose-dependent relationship. In addition to seeking understanding of the mechanisms involved, the project will investigate the ability of other antibiotics to affect the positive results without the toxic side effects. Dr. Stephen Arnoczky Michigan State University

FURTHER EVALUATION OF SHOES AND IMPACT TRAUMA The G forces which have been shown to be increased when toe grabs are used can be measured and recorded by attaching accelerometers to the hoof. The ongoing research by this scientist and his team will continue the work GJCF has been funding, of developing a safer shoe for horses running at high speeds. Moreover, the method of shoe attachment is indicated to be a factor in the impact on the limb, and this study will evaluate options of shoe attachment. The end goal is development of a safer shoe design, and will have the secondary component of providing a

data acquisition system that can enhance evaluation of any aspect of the interface between hoof and track. Dr. David Nunamaker University of Pennsylvania

IS NITRIC OXIDE INVOLVED IN DELAYED UTERINE CLEARANCE? Some subfertile mares are unable to clear the uterus after it is contaminated during breeding, a condition which destroys the embryo. Various projects, including some funded by this Foundation, have shown that inability to clear the uterus results from abnormal muscle contraction. Understanding what causes the abnormal contractions is a next step, and this specific proposal will investigate whether nitric oxide is a cause. Steps include determining which cells of the uterus are capable of producing nitric oxide, a compound which reduces cell function, and then comparing the amount of this substance in normal versus subfertile mares. Dr. Sherri Rigby Texas A & M University

MUSCLE GLYCOGEN METABOLISM IN HORSES So-called “tying-up” syndrome is a major muscle problem which keeps many young race horses on the shelf for extended periods of time. This project seeks nutritional explanations for the problem as well as addressing aspects of athletic performance. The author has a strong record in exercise physiology. The aim is to determine the role of diet in computing how quickly horses can replenish muscle glycogen concentration. Dr. Kenneth Hinchcliff Ohio State University

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JOURNAL OF EQUINE VETERINARY SCIENCE