Metabolic and anatomical adaptations of heavy-bodied chicks to intermittent feeding. 2. Pancreatic digestive enzymes.

1. Activities of digestive enzymes in meat-type chickens under ad libitum or alternate-day feeding were determined from 14 to 83 d of age. 2. Final body weight of intermittently fed birds attained 75% of that of the ad libitum-fed controls. 3. When compared with the ad libitum-fed counterparts, a marked increase in the relative weight of the pancreas and intestinal contents were found on repletion days. On depletion days the relative weights of the pancreas and of the intestinal contents were about half those found in ad libitum-fed birds. 4. The activity of the digestive enzymes in the pancreas, expressed as U/g pancreas or U/kg body weight, was not affected consistently by the feeding regime. In the small intestine a marked increase in relative activity (U/kg body weight) was observed on repletion days and a marked decrease on depletion days as compared with ad libitum-fed controls. The activities per g intestinal contents following food restoration did not differ significantly from those of ad libitum-fed controls except for trypsin, which was higher in the former. On depletion days the activities per g intestinal contents were lowest, lipase excepted.