EFFECT OF EXCESSIVE DOSAGES OF THYROID ON THE DOMESTIC FOWL

Abstract

1. Single doses of desiccated thyroid ranging from 8 to 30 grams although producing physiological shock were not lethal to hens. 2. Single doses of 30 to 35 grams proved lethal to two out of three capons. 3. Cockerels are able to withstand single dosages as large as 35 grams. 4. Single doses varying from 8 to 35 grams cause a loosening of the feathers in from 3 to 10 days. Molt commences in from 3 to 10 days. 5. Depigmentation occurs during feather renewal following the precipitous molt. It was quite noticeable in 30 days after feeding. 6. A silky texture to the feathers was noticeable following thyroid feeding. 7. The hooks or hæmules are absent from the barbs in the feathers growing in immediately following thyroid feeding in larger than physiological dosages. 8. Thyroid feeding in large doses causes a change in nervous temperament of the Plymouth Rock, making it highly excitable. 9. Loss in body weight follows feeding of thyroid in large dosages, more especially in capons. 10. Thyroid feeding has a depressing effect on body temperature when fed in large dosages, capons showing a greater depression than cockerels.