Energy relationships in growing chickens given daily injections of corticosterone

Abstract

The energetic efficiency of growing chickens given daily injections of corticosterone was investigated by measuring metabolic activity and energy balance. Water consumption increased significantly within the 1st day of treatment; food consumption increased by the 3rd day of treatment. Growth rate, which was suppressed during the first 2 days, returned to normal by the 3rd day of treatment. Excreted water, dry matter and uric acid increased within the 1st day of treatment. Heat production was not changed by treatment; the CO2:O2 respiratory ratio (RQ) was increased by the 3rd day and exceeded 1.0 on days 4 and 5 of treatment. Leg muscle weight was decreased and abdominal fat and liver weight were increased by corticosterone treatment. Balance data indicated that energy absorption efficiency was decreased and energy retention efficiency was increased by corticosterone treatment, confirming the RQ and carcass findings that greater amounts of energy were stored as fat.