VITAMIN E SUPPLEMENTATION IN HORSES WITH NEUROLOGIC DISORDERS

摘要

Vitamin E functions as a biological antioxidant, preventing the oxidation of unsaturated lipids within cellular and subcellular membranes by neutralizing production of free radicals. Through this mechanism, and potentially other mechanisms yet to be elucidated, vitamin E serves to maintain normal neuromuscular function. Several specific equine diseases develop in the face of vitamin E deficiency. These include nutritional myodegeneration, neuroaxonal dystrophy and equine degenerative myeloencephalopathy in young animals. Adult horses deficient in vitamin E may develop a vitamin E deficient myopathy or equine motor neuron disease. Treatment with vitamin E is usually instituted in an attempt to reverse clinical signs. However, selecting the type and amount of vitamin E to supplement can be challenging for veterinarians because the bioavailability and potency varies widely among commercial supplements. Most vitamin E supplements consist of natural or synthetic forms of a-tocopherol because it is the most biologically active and most researched isoform of vitamin E. Vitamin E, however is a complex nutrient consisting of eight closely-related fat-soluble naturally occurring compounds that form two groups; tocopherols (saturated) and tocotrienols (unsaturated). Within each group, there are four individual isoforms (a, p, y and 5). The purpose of these proceedings is to review the equine neuromuscular disorders related to vitamin E deficiency and data on serum and tissue responses to commercial vitaminE supplements.