Hypophysectomy of birds III—Effect on gonads, accessory organs, and head furnishings

Abstract

It is now well known that removal of the anterior lobe of the pituitary body in mammals leads to atropy of the gonads and thence of the accessory reproductive organs, but this generalization has not hitherto been extended to birds. It would be expected that hypophysectomy would result in atrophy of the secondary sexual characters directly dependent on the gonad. Such characters are rare in experimental mammals, but the comb of the male fowl is an obvious example. The present paper records observations on the changes in the testis and vas deferens, in the ovary and oviduct and in the head furnishings of birds after removal of the pituitary body. Plumage changes, which do not depend on the testes and are only indirectly linked with the ovary, are not included.