Vitamin E and selenium for reproduction of the dairy cow.

Selenium injections and oral vitamin E supplementation prepartum were related to incidence of retained placenta, metritis, and cystic ovaries in a 2 X 2 factorial experiment. Groups were: 1) selenium and vitamin E, 2) vitamin E, 3) selenium, and 4) control. Incidence of retained placenta was 17.5% in cows of groups 2, 3, and 4, whereas it was reduced to 0% in cows receiving both selenium and vitamin E. Incidence of metritis was 60% for cows injected with selenium and 84% for those not receiving selenium. Cystic ovaries were diagnosed in 19% of cows injected with selenium, and incidence was 47% for cows not treated with selenium. Supplementation of vitamin E was required in addition to selenium for prevention of retained placenta of cows fed stored ensiled forage, and prepartum selenium injections were effective for reducing the incidence of metritis and cystic ovaries during the early postpartum period.