The influence of thyroid hormone and androgen on comb growth in the White Leghron cockerel.

Abstract

INTRODUCTION IT has been shown (Caridroit, 1941; Simmons, 1943; Blivaiss, 1947, and others) that comb growth is partly dependent upon the presence of thyroid hormone. Simmons reported that the growth of the comb in the White Leghorn capon could be increased by the administration of thyroxine and that the effect was roughly proportional to the dose. Blivaiss presented data showing a greater increase in growth of combs of Brown Leghorn capons and thyroidectomized males following the simultaneous administration of thyroxine and testosterone propionate than with either alone. Data submitted in the present paper substantiate some of the earlier work and support the suggestion of a synergistic action of thyroid hormone and androgen in the promotion of comb growth in the White Leghorn fowl. MATERIALS AND METHODS Changes in the weight of the comb, thyroids, and gonads, in response to various treatments designed to control the level of circulating thyroid hormone and androgen were studied. Animals were subjected t...