The Metabolic Fecal Nitrogen Excretion of the Young Calf and the True Digestibility of Casein

Abstract
The metabolic fecal nitrogen excretion of 4 young dairy calves has been determined by feeding casein labeled with radioactive phosphorus, P32, incorporated into a purified liquid diet. The average metabolic nitrogen excretion was 0.27 gm per 100 gm dry matter intake. The validity of this value is discussed. The true digestibility of the nitrogen of the casein used in these studies averaged 93.5%.