THE EFFECT OF THYROXIN ON THE SOCIAL ORDER IN FLOCKS OF HENS1

Abstract

Thyroxin, injected into individuals from different social levels in flocks of white leghorn hens, produced no changes in social status so long as the treatment did not initiate the combination of changes that accompany severe molting. Thyroxin had no noticeable influence on success in initial pair contacts with strange hens when the amt. was relatively small and produced no other readily observable, or only general effects. Thyroxin treatment markedly decreased such successes when the hens received doses which soon produced a decided molt with accompanying physiological changes. The largest doses administered induced a sudden and complete molt and resulted in the loss of social position of 2 high ranking hens. In addition these larger doses caused a loss of body wt., inhibition of laying, decrease in size of comb, and a general lessening of activity. There is a discussion of the general implications of these results on the social order in flocks of hens.