Demonstration of thyroglobulin in the thyroid glands of obese strain and normal white leghorn chicken embryos.

The earliest detectable presence of thyroglobulin has been measured in Obese Strain and normal White Leghorn chicken embryos of different ages by means of indirect immunofluorescent staining, double diffusion in gel, and haemagglutination-inhibition. Thyroglobulin could be demonstrated as early as the ninth day of incubation of OS or normal eggs. No antigenic differences could be demonstrated between thyroglobulin from OS and normal chickens or between thyroglobulin from embryos and from adult chickens. The implications of these findings for the pathogenesis of the autoimmune thyroiditis developed in the OS chickens are discussed.