Vitamin E treatment of weaner sheep. II. The effect of vitamin E responsive subclinical myopathy on liveweight and wool production

Abstract

Nutritional myopathy occurs as both a clinical and subclinical disease in weaner sheep in Western Australia during summer and autumn. The effect of subclinical nutritional myopathy (SCNM), caused by vitamin E deficiency or combined vitamin E and selenium deficiency, on liveweight and wool was investigated. During the period of SCNM there was no significant difference in liveweight gain in sheep with and without the disease in any of the experiments. Initial liveweight in one experiment was significantly (P < 0.05) higher in sheep that were to develop SCNM during the course of the experiment. In vitamin E deficient-selenium adequate SCNM, there was no difference in wool growth over the period of the disease and no differences in any of the wool measurements at shearing. At 2 sites, the greasy and clean fleece weights were significantly (P < 0.05) greater in a group of sheep diagnosed with more severe SCNM compared with sheep without SCNM. It was concluded that unlike the clinical disease, SCNM was unlikely to cause any economic loss.