Relation between Age of Calf, Blood Glucose, Blood and Rumen Levels of Volatile Fatty Acids, and in Vitro Cellulose Digestion1,2

Abstract

Summary Blood and rumen juice were collected from 18 male Holstein calves at 1 week of age and every week thereafter until 15 weeks of age. Results of the analyses show a lowering of blood glucose levels concurrent with increasing levels of blood volatile fatty acids. At the same time, rumen juice volatile fatty acids and per cent in vitro cellulose digestion increased as the calves advanced in age. The significance of these findings and the possible relationship between these factors are discussed.