Thirty-four pregnant Shorthorn cows were fed during the winter either grass silage from first crop material or rapeseed silage, both low in selenium content (less than 33 nanogram/g DM). Serum glutamic oxalacetic transaminase (SGOT) determinations were performed before and after the calves went to the pasture. There was no evidence either clinically, biochemically (SGOT) or at post-mortem examination, of any nutritional muscular dystrophy (NMD) disorder in the 34 calves, despite very low plasma selenium levels (4 to 5 ng/ml plasma).

An implantation technique using a slow-release selenium pellet also was evaluated as a means of controlling the disease. Fifteen calves from a total of 33 calves born to cows given a dystrophy-producing hay during the winter, were implanted a few days after birth with a pellet containing 15 mg of selenium. Four out of 18 calves in the control group showed clinical symptoms of NMD and two died with NMD lesions. SGOT levels in the implanted calves were normal during the experiment and none was affected by NMD. Plasma selenium levels in the implanted calves were significantly higher than in the deficient controls at each sampling period, but within normal ranges previously reported.