Effect of Adding Dried Whey to Starter Diet of Early and Late Weaned Calves

Abstract

Forty-four Holstein calves, 20 males and 24 females, were randomly assigned to one of four treatments in a 2×2 factorial designed experiment. Treatments consisted of early (35 d) versus late (70 d) weaning and the feeding of a pelleted starter diet containing either 0 or 24.5% dried sweet whey. Calves were housed in individual, elevated, shaded pens. Whole milk was fed at 10% of body weight adjusted weekly. The assigned starter diet and water were provided free choice beginning on the 8th d of the trial. Intakes of milk and starter diet were recorded daily. Body weight, heart girth, and wither height measurements were recorded weekly during the 14-wk trial. Calves fed the starter diet containing whey consumed less dry matter (119.2 vs. 150.7kg) and had a lower rate of gain (.63 vs. .72 kg/d) than those fed the control starter ration. Late weaned calves consumed less starter (115.8 vs. 145.0kg) and gained more rapidly (.74 vs. .61 kg/d) than early weaned calves. Bull calves were more efficient converters of dietary dry matter into body weight gain than heifer calves, and late weaned calves were more efficient than early weaned calves. Inclusion of whey in the starter ration did not influence feed conversion. It was concluded that the addition of whey at 24% of a pelleted starter diet depressed intake and rate of gain of calves.