Studies on Milk Fever in Dairy Cows. IV. Prevention by Short-Time, Prepartum Feeding of Massive Doses of Vitamin D

Abstract

Various levels of vitamin D[long dash]5, 10, 20, and 30 million units/day in the form of irradiated dry yeast and viosterol (irradiated ergosterol in oil)[long dash]were fed to mature Jersey cows for 3-8 days prepartum. The maintenance of a high blood serum level of Ca and P during the critical postpartum period was used along with clinical observations as criteria for determining the effectiveness of various levels of vitamin D feeding in preventing milk fever. The physiological basis for these blood changes is discussed. Some protection was attributed to the 2 lower levels of vitamin D feeding, and complete protection to date has resulted from the higher dosages. Thus, the feeding of 30 million units of vitamin D/day for at least 3 days and preferably not more than 7 days prepartum and 1 day postpartum offers a simple, safe, and effective method for milk fever prevention. Minimum effective dosage of vitamin D for milk fever prevention was not accurately determined.