Selenium/vitamin E: role in disease prevention and weight gain of neonatal calves.

A 3 X 2 factorial arrangement of treatments comparing 0, 1, or 2 injections of a selenium/vitamin E preparation and feeding of starter commencing at 14 or 28 days of age was used to examine effects of supplemental selenium/vitamin E on health and growth of neonatal calves. Dosage per injection was .078 mg selenium and 5.4 international units of vitamin E per kg body weight. Neither a single injection at birth nor two injections (birth and day 14) reduced incidence of respiratory diseases or improved weight gains in unstressed calves. Calves first offered starter at 14 days as compared with 28 days gained more weight in the 56 days. A single injection of selenium/vitamin E at birth increased selenium of blood serum at day 14 by 87%, and a second injection increased selenium of blood serum at day 28 an additional 10%. Selenium of blood serum of calves not given an injection decreased linearly from birth to day 56. Calves first fed starter at day 14 had lower concentrations of selenium of blood serum from day 28 to 42 than calves first offered starter at day 28. Glutathione peroxidase activity of erythrocytes was higher in calves receiving one or two injections of selenium/vitamin E than in control calves; however, a lag of 4 to 5 wk occurred between injections and elevation of glutathione peroxidase activity.