Effect of prepartum supplementation of selenium and vitamin E on serum Se, IgG concentrations and colostrum of heifers and on hematology, passive immunity and Se status of their offspring.

Forty heifers at the late stage of gestation were randomly assigned into five groups. Heifers were balanced for age, weight, and time of calving in each group. Four and 2 weeks before expected time of calving, the heifers were injected with 0 ml (C), 10 ml (T1), 20 ml (T2), 30 ml (T3), and 40 ml (T4) Se and VE supplements, respectively. Each milliliter of the supplement contained of 0.5 mg Se as sodium selenite and 50 IU of dl-alpha-tocopheryl acetate. Blood samples were collected from the heifers 4 weeks before expected calving and at calving day and from the calves at birth and 7 days of age. The serum Se and immunoglobulin G (IgG) concentrations, white blood cell and differential leukocyte counts were measured. The Se concentrations in the sera of the heifers before the injections of Se and VE supplements were the same among the groups (P > 0.05), but after calving were significantly increased in the treated heifers (P < 0.05). Similarly, the serum Se levels of calves of the treated heifers were higher (P < 0.05). The Se concentrations in the colostrums of the heifers were affected by treatments (P < 0.05). Colostrum and daily milk productions at 8-week lactation were increased in treated heifers compared with the controls (P < 0.05). Likewise, the milk somatic cell counts decreased in the treated heifers compared with the controls. The changes of the mean serum IgG levels did not differ among calves (P > 0.05). The white blood cell counts were higher in calves of heifers in groups T3 and T4 compared with the control group at 7 days of age (P < 0.05).