Capons did not crow, did not try to mate with females, and did not fight aggressively with other males. Importantly, Berthold also transplanted testes into capons. When a testis was transplanted, these subjects showed normal aggressive behaviour and secondary sex characteristics.

Will a capon still crow?

However, while castrated roosters, or capons, are known to be more docile than their fully equipped brothers, there is little evidence that castrating a full-grown rooster prevents it from crowing. ...

Will Caponizing a rooster stop crowing?

Caponizing minimizes crowing, but doesn't entirely stop it.

Caponizing is a type of surgery that severs or removes a cock's testicles, which are tucked inside the bird's body. ... But it doesn't stop the crowing, and fitting the collar tight enough to discourage crowing without strangling the bird can be tricky.