He removed the testes of immature male chickens (the castrated animals are called capons) and found a decrease in some secondary sex characteristics (comb, wattles) and male-typical behaviours (11). Capons did not crow, did not try to mate with females, and did not fight aggressively with other males.

Are capons illegal?

No U.S. state or federal regulations prohibit the practice of caponizing cockerels—castrating male chickens under one year of age. ... Caponizing has been banned in the United Kingdom due to animal welfare concerns and should be disallowed in the United States.

Do cockerels always Crow?

Like all birds, roosters sing – or crow – in a daily cycle. Almost all animals have daily cycles of activity known as circadian rhythms that roughly follow the cycle of day and night. Roosters anticipate sunrise to get a head start on their daily hunt for food and defense of territory.