Clinical and biochemical responses were studied after taking the measures to prevent nutrition muscular dystrophy in young cattle in the given ecological conditions. Analyzing the biological material (blood, hair, feed, soil), we found the sufficiently high saturation of heifer organisms with the microelement selenium and on the contrary, vitamin E deficiency. Sensitive indicators of the break-down of muscular tissue were the enzymes aspartate aminotransferase (AST), alanine aminotransferase (ALT), and mainly creatinine kinase (CPK): the activities of these enzymes increased significantly after the heifers had been driven to pasture. The stay of animals in the run to get them used to the physical load before going to the pasture was not found to be a sufficient measure to prevent muscular nutrition myodystrophy if the animals had not been administered vitamin E and selenium supplements. Of the one hundred heifers we examined, seven animals began to show the signs of nutrition muscular dystrophy; none of these animals had been administered vitamin E and selenium supplements.