2,195. Castration

Hilchos Issurei Biah 16:9

Whenever we say that a man may not marry in because of a genital issue, the implication is that his injury was not congenital, such as if his male member was injured by a person or a dog, or he was struck by something sharp, etc. However, if he was born with crushed testes or a severed organ, or without testes, or if he got sick and these organs stopped functioning, or if an ulcer in these organs caused them to wither or to be amputated, then he may join the general marriage pool because all of these were caused by Heaven.

Hilchos Issurei Biah 16:10

It is prohibited to castrate any male, among humans, domesticated animals, wild animals and birds, be they kosher or non-kosher. This prohibition applies both in Israel and elsewhere. While Leviticus 22:24 says, “Do not do this in your land,” our oral tradition teaches that it applies everywhere. The meaning of that verse is that one may not act this way with Jews, not with one’s own body nor with others. Whoever castrates a human or an animal anywhere is subject to the penalty of lashes under Torah law. Even if one castrates a person who was already castrated, he is subject to lashes.