New Research Reveals Role of Androgen Receptors in Sexual Development in Birds

• A study by the Max Planck Institute of Biological Intelligence and Technical University, Munich, suggests that androgen receptors are as crucial for sexual development and fertility in females as in males.

• Both male and female chickens devoid of androgen receptors were found to be infertile, but the males developed testicles and females ovaries, and produced gonadal hormones.

• Female chickens lacking androgen receptors failed to develop and lay eggs.

• Despite sex-specific peculiarities like tail feathers, spurs, and differences in body size and weight, their sexual behaviors failed to develop.

• The study suggests that androgen hormones, a steroid hormone, are a key player in avian sexual development, and that testosterone action via androgen signaling is critical in both male and female birds.

• The study also found that the bursa of Fabricius, a chestnut-shaped lymphoid organ in birds, is involved in sexual growth and maturation.

• The study found that male chickens without androgen receptors didn’t crow even when exposed to testosterone a week after hatching.

• The neural circuits responsible for crowing behaviour couldn’t fully develop in the absence of the receptors.

• The study also found that comb development, an important sign of sexual maturation among chickens, didn’t occur in male or female chickens birds without androgen receptors, even after they were exposed to testosterone.

• The study suggests that androgen signalling plays a crucial role in the development, fertility, physiology, and appearance of both sexes as well as sex-specific crowing behavior in males.