EFFECTS OF SELENIUM AND VITAMIN-E ADMINISTRATION DURING A LATE-STAGE OF PREGNANCY ON COLOSTRUM AND MILK-PRODUCTION IN DAIRY-COWS, AND ON PASSIVE-IMMUNITY AND GROWTH OF THEIR OFFSPRING

Objective-To determine effects of selenium (Se) and vitamin E (VE) adm inistration in late pregnancy on Se status, plasma immunoglobulin conc entrations, and colostrum and milk production of dairy cows, and on Se status, passive immunity, and growth of their offspring. Animals-25 H olstein cows and their offspring. Procedure-3 and 1.5 weeks before cal ving, sodium selenite (5 mg/100 kg of body weight) and d,l-alpha-tocop heryl acetate (25 lU/100 kg) were administered to 13 cows. The other 1 2 cows were not treated. Se status was assessed by measurement of glut athione peroxidase activity of erythrocytes (GSH-Px-E). Results-The 13 treated cows had higher (P < 0.01) GSH-Px-E values at calving and dur ing the first 12 weeks of lactation. Changes in plasma immunoglobulin concentrations before or after calving did not differ between the 2 gr oups of cows. During the first 36 hours after calving (4 milkings), tr eated cows produced 22% more colostrum than did their nontreated count erparts (P < 0.005). Percentages of colostral immunoglobulins did not differ between the 2 groups. During the first 12 weeks of lactation, t reated cows produced 10% more milk than did nontreated cows (P < 0.005 ). GSH-Px-E values at birth and 28 days of life were significantly hig her in calves from treated cows. Plasma immunoglobulin concentrations and body weight during the first 56 days after birth did not differ be tween calves born to treated or nontreated cows. Conclusions and Clini cal Relevance-Cows given Se and VE in late pregnancy produce large qua ntities of colostrum and milk. Colostrum produced from cows given Se a nd VE is suitable to feed newborn calves and to be stared for later us e. Improvement of Se status in calves born to cows given Se and VE in late pregnancy is not beneficial to passive immunity and growth.