ABSTRACT

Plasma concentrations of gastric inhibitory polypeptide (GIP) were measured in preruminant goat kids before and after consumption of milk, skimmed milk or solutions of milk fat, lactose, glucose or casein plus lactose. GIP concentrations increased significantly within 1 h of consumption of milk or milk fat, and were elevated for the remainder of the 5-h sampling period. The integrated mean change in GIP concentration during this period did not differ between these two meals. GIP levels were slightly increased above basal values 5 h after skimmed milk consumption, probably reflecting the absorption of a small amount of fat, but overall there was no significant GIP response to this or to any of the other test meals. The marked increase in GIP concentration after a milk feed indicates a physiological role for the hormone in preruminants but, in contrast to the situation in simple-stomached animals, carbohydrate absorption does not elicit GIP secretion in the preruminant goat. The data strongly suggest that fat is the major nutrient to stimulate GIP secretion in these animals.

Journal of Endocrinology (1993) 138, 167–173