The pancreatic insulin content and its relationship to plasma glucose and free fatty acid concentrations in the embryo and neonatal chick.

1. An inverse relationship was found between the plasma glucose and FFA concentrations of embryos aged between 14 and 20 d. 2. Both the plasma glucose and FFA concentrations were constant during hatching. 3. The insulin content of the pancreas increased between 14 and 20 d but fell during hatching.