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Determinacja Płci I Rozwój Gonad Kury Domowej

2019, Kosmos

Abstract

Our understanding of sex determination and sexual development in birds is based mainly on findings from chicken. In this species, as in other birds, female sex is heterogametic (ZW), and the male sex is homogametic (ZZ). So far, a master sex-determining gene is unknown. DMRT1 is considered as a crucial gene for the male sex determination. This gene is located in the Z chromosome and is expressed in the developing male gonads. However, in ovarian development, aromatase, an enzyme synthesizing estrogens, appears critical. Interestingly, in birds, the ovary and oviduct develop only at the left side, while the right gonad becomes reduced. Estrogens have an important role in the sexual development in birds. Accordingly, a modulation of aromatase activity can be used to obtain birds with sex reversal. The exact role of testosterone in testis development remains unclear. However it was shown that hormone plays an important role in the secondary sex features development. The compilation of previous findings reveals that further studies on sex determination in birds are required to fully describe this phenomenon.