Development of the Testes in Female Domestic Fowls Submitted to an Experimental Sex Reversal During Embryonic Life

Abstract

The sex differentiation of the female chick embryo can be totally inverted toward the male sex by an early extraembryonic testis grafting. This sex reversal remains permanent, as shown by three adult fowls described in this paper. They possess two testes associated with normally differentiated male excretory ducts and their Müllerian ducts have regressed. The development of male sex characteristics such as external features, behavior and complete spermatogenesis is evidence that these cocks have endocrine and exocrine capabilities similar to those of normal cocks. Although these cocks were able to mate with female fowls, they were sterile. A mechanism is discussed by which grafted testes induce such modifications in females. Hypotheses considering the heterogametic sex (female in birds) as exerting a dominant influence on the phenotypic sexual differentiation can be discarded in light of our results because a homogametic testis provokes the definitive sex inversion of a female.

Anti-Müllerian hormone and freemartinism : inhibition of germ cell development and induction of seminiferous cord-like structures in rat fetal ovaries exposed in vitro to purified bovine AMH

“…Few (Benhaim et al, 1982). Other investigators (Jost et al, 1972 ;Vigier et al, 1977 ;Stoll et al, 1980 ;Rashedi et al, 1983), struck by the similar timing of ovarian lesions and Mullerian regression, have proposed that both are mediated by the same substance, namely AMH. Using AMH purified by immunochromatography on a monoclonal antibody (Picard and Josso, 1984), we are now in a position to confirm this hypothesis.…”

Disorders of Sexual Development in Poultry

“…Interestingly, if a late embryonic testis is grafted beside a developing ZW gonad in ovo, it induces testis development. These studies again show that embryonic urogenital development in chickens can be modified by hormones [Rashedi et al, 1983].…”

Differential Development of Sex-related Characters of Chickens from the GSP and PNP/DO Inbred Lines after Left Ovariectomy

“…It has also been elucidated that elongated spermatids and sperm carrying the W-chromosome from chickens sex reversed by using a non-steroidal aromatase inhibitor possess fertilizing ability similar to normal male sperm carrying the Z-chromosome [20]. In sex reversal experiments using left ovariectomy with the combination of extraembryonic testis grafting and chemical treatment, varying results in the degree of sex reversal or masculinization have been reported [21,22]. Considering the various reports of sex reversal experiments, it has never been reported whether strain preferences or the genetic background of the experimental animals are a contributing factor in the degree of sex reversal of the female chicken.…”