Selenium supplementation of young red deer (Cervus elaphus).

Two selenium (Se) supplementation trials were conducted in successive years involving a total of 70 red deer calves 3-15 months of age grazing pasture containing 30-57 ppb of Se on a dry matter basis. The trials compared growth rate, whole blood Se and glutathione peroxidase (GSHpx) concentrations of calves which received periodic doses of oral Se or a single injection of barium selenate (equivalent to 50 mg Se) or no Se supplementation. There were no significant weight gain differences between treated and untreated groups in either trial. Whole blood GSHpx levels were strongly correlated with blood Se levels (r = 0.9278) and produced the following regression equation: GSHpx = 0.0155 Se - 2.292. In both years the 3 month old calves had GSHpx levels of 6-9 kU/I which probably derived from maternal transfer of Se. The GSHpx levels in unsupplemented calves declined from these levels to a minimum in winter (group means approximately 2.6) and then progressively rose the following spring and summer. Periodical oral dosing with Se or a single injection of barium selenate significantly elevated blood Se and GSHpx levels throughout the trials.