Feeding behavior in monkeys with spontaneous diabetes mellitus.

In our laboratory, monkeys (Macaca mulatta) that attain middle age (10-14 years) and a body weight of over 15 kg often develop spontaneous diabetes mellitus. In some animals the development of the disease is accompanied by polyphagia and polydipsia. The polyphagia appears to be in response to loss of body weight. Gross estimates of energy balance in diabetic monkeys indicate that the daily maintenance cost (kcal) of diabetes is greater during the untreated phase of the disease than in the pre-diabetic state.