RESPONSE TO WEANING AT TWO TO FIVE WEEKS OF AGE BY THE YOUNG DAIRY CALF

Abstract

In two experiments Ayrshire and Holstein bull calves were weaned off whole milk onto dry feed at various ages, ranging from 14 to 35 days, to determine the earliest age at which calves may be weaned successfully. Ayrshire calves were weaned at 14, 21 and 35 days with no significant differences in weight gains or feed intake to 15 wk of age. Holstein calves were weaned off whole milk or fermented colostrum at 17, 21, 24, 28 and 35 days of age with no significant differences in weight gains and feed intake to 12 wk of age. Also, the feeding of either fresh whole milk or fermented colostrum did not sigificantly affect animal performance. Several calves weaned at less than 21 days, in each experiment, refused to eat dry feed. Post-weaning deaths of several calves weaned at 21 days were attributed to prolonged pre-weaning scours or illness at time of weaning. It was concluded that healthy male calves may be weaned successfully at 21 days of age but weaning should be delayed for calves afflicted with scours or other illness. Agressive eaters may be weaned as early as 14 days of age but some calves weaned at less than 21 days of age may encounter problems in adapting to dry feed.