Age-related changes in carbohydrate tolerance in healthy neonatal calves

Calves at 3 to 4 days of age had higher plasma glucose concentrations during glucose and lactose tolerance tests (orally administered glucose and lactose) than when the calves were 8 to 9 days old. These observations may be accounted for by decreased insulin secretion and/or insulin sensitivity of the target tissues. Lower hepatic glucokinase activity in neonates also may allow increased passage of splanchnic glucose to the system circulation.