Effects of Insulin-Induced Hypoglycemia and Hypoacetoemia on Eating Behavior in Goats

Abstract

Severe hunger and eating are caused by hypoglycemia induced by insulin injections in monogastric animals. Two experiments were done to test for this response in ruminants. Protamine zinc insulin injec- tions were given to goats for a period of 14 days in Experiment I and on one day in each of three one-week tests in Experi- ment II. The first experiment tested for long-term changes in feeding behavior, while the second tested for short-term changes during an induced hypoglycemia. In both experiments the goats suffered from hyperinsulinemia and severe hypo- glycemia, although no convulsions or coma were observed. Hypoglycemia was accom- panied during its initial stages by a low serum acetate concentration. There was no trend for goats to eat to correct the hypo- glycemia. Thus the response of goats differs from that of intact monogastric ani- mals. Ruminants apparently do not have the response of other mammals of eating to correct hypoglycemia. It has previously been inferred that hypoacetoemia would cause increased feed intake in ruminants; this response did not occur, although the serum acetate concentration decreased to only one-third of normal levels.