Response of Blood Glucose and Plasma Free Fatty Acids to Fasting and to Injection of Insulin and Testosterone in Chickens

Plasma free fatty acids (FFA) and blood glucose levels were measured in normal cocks at fasting and after eating, and in normal and depancreatized hens and cocks at fasting and after injections of insulin preparations or glucagon-free insulin; testosterone was injected only in normal hens and cocks. Plasma FFA levels increased at fasting and decreased after eating. Insulin administration increased plasma FFA levels of practically all chickens studied. The increases were greater in males than in females when preparations of insulin were used; no such sex difference occurred when glucagonfree insulin was used. Testosterone administration increased plasma FFA levels of cocks but not of hens; it was without effect upon blood glucose levels. Blood glucose levels decreased in response to the injection of insulin; the decreases fluctuated widely and showed little differences between the 2 insulins or between normal and depancreatized chickens. (Endocrinology81: 1001, 1967)