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

Abstract

Blood and rumen fluid samples were collected from 18 male Holstein calves at 1 week of age and every week thereafter until 15 weeks of age. Blood glucose levels declined concurrent with increasing levels of blood volatile fatty acids. Rumen fluid volatile fatty acids increased with age, as did % in vitro cellulose digestion. These changes were correlated statistically. Calves fed milk replacement showed lower initial blood levels of glucose than did those fed milk.