Blood glucose and tissue glycogen concentrations in normal and deutectomised chickens during the first twelve hours...

1. Blood glucose, plasma free fatty acids and amino nitrogen, and liver, skeletal muscle, heart, brain and lung glycogen were determined in normal and deutectomised (stripped of yolk sac at hatching) chickens 45 min, 2, 4, 6, 9 or 12 h after hatching. 2. In the normal bird blood glucose decreased by 41% in the first hour after hatching, returning to the hatching value at 12 h. The free fatty acids and the amino nitrogen values did not change much during the 12-h period. Liver glycogen increased by 86% at 2 h, decreasing slightly before returning to hatching value at 12 h. 3. In the deutectomised bird blood glucose was essentially constant and almost equal, during the 12-h period, to that at hatching. Free fatty acids and amino nitrogen were lower after 1 h than at hatching and liver glycogen after 1 h declined to 50% of that at hatching, declining further with time.