Protein and Energy Requirements of the Young Calf

Abstract

Three experiments were conducted to study the protein and energy requirements of the young calf and the relative efficacy of various milk replacers, by using 88 three-day-old male Holstein calves from 4 to 60 days of age. The energy requirement for maintenance was 48.2 kcal digestible energy daily per kilogram of body weight; the requirement for growth was 370 kcal per 100 g gain in body weight. The N retention was 2.56 g per 100 g gain in weight. The digestibilities of N, ether extract and energy; weight gains and fecal consistency showed significant (P< 0.01) linear decreases when increasing levels of corn distillers dried solubles were substituted for dried skimmilk and lactose. When the substitution of corn distillers dried solubles was on the basis of digestible protein (as determined in this study), differences in growth rates of calves on diets providing 0, 20, and 35% of the digestible protein from corn distillers dried solubles were much smaller and not statistically significant at P = 0.05.