Factors Affecting Requirement and Use of Crude Protein in Calf Starter

Abstract

In five trials 385 calves under 12 wk of age were used to study effects of factors related to utilization of crude protein on performance of young dairy calves. Calves abruptly were changed to starters containing 1.35% urea without apparent toxicity, and in one trial urea was as effective as soybean meal as a protein supplement. Sulfur supplementation to starters already containing .2% sulfur apparently stimulated starter consumption by calves previously adapted to urea. Dried whey was beneficial in starters containing urea when calves had been fed dry feeds for a short time. The requirements for protein exceeded 11.7% of air dry starter for weaned calves to 12 wk of age.