Degenerative Myopathy With Myoglobinuria in Yearling Cattle

Abstract

SUMMARY The clinical, biochemical and pathological observations made during an outbreak of acute myopathy in yearling cattle which followed turnout to spring pasture are described. The affected cattle were between 13 and 20 months old and the weight range was 225–320 kg. The diet fed during the winter was vitamin E and selenium deficient. In one case the vitamin deficiency was exacerbated by preservation of the cereal portion of the diet with propionic acid. Other predisposing factors were the unaccustomed exercise following winter housing and the onset of inclement weather after turnout. The condition is compared with enzootic muscular dystrophy of young calves, and it is concluded that the condition is an atypical manifestation of the calf disease but affecting older animals. New husbandry practices, particularly the storage of high moisture grain, seem likely to increase the frequency of the condition.