Effect of dietary vitamin E on immune responses of calves.

The effect of vitamin E on humoral and cell-mediated immune responses in calves was determined, and plasma vitamin E and immunological status of calves under normal herd management were studied. Twelve newborn calves were fed skimmed colostrum for 2 days and thereafter skimmed milk plus vitamin E-stripped lard and emulsifying agents. Six calves each orally received 0, and six each orally received 1 g of DL-alpha-tocopherol acetate daily. Rations were supplemented with trace minerals and vitamins A and D. Twenty calves were fed colostrum for 3 days and thereafter milk and dry feed. At 6 wk, mean plasma vitamin E concentrations (micrograms/100 ml) for groups were 71, 639, and 155, respectively; and mean serum glutamic oxalacetic transaminase concentrations (IU/liter) were 320, 61, and 43, respectively. Mean serum immunoglobulins concentrations (mg/100 ml) were: G1, 1079, 1168, and 1315; G2, 488, 562, and 432; A, 37, 53, and 35; M, 151, 118, and 110. Mean lymphocyte stimulation indexes were 76, 220, and 152, respectively. At 6 wk there were large but nonsignificant differences in mean indexes among groups.