Thermoregulatory ability and the thyroid gland: Their development in embryonic Japanese quail ( Coturnix c. jaaponica)

Abstract

1. During development, fertile Japanese quail eggs show some increase in resistance to cooling. 2. During development, mean thyroid follicle cell height and total thyroidal iodine increase rapidly, until shortly before hatching. 1. One to 2 days before hatching, follicle cell height and thyroidal iodine content are abruptly reduced, but both return to former levels on the day of hatching.