Halakhah for Chagigah 28:1

Not to castrate one of all of the species: To not castrate one of all of the species - not a man and not a beast and not a bird, as it is stated (Leviticus 22:24), "and in your land you shall not do [it]." After the verse mentioned, "And a crushed, and a pounded and a disconnected and a cut," which is stated about the [sexual organs], it stated, "and in your land you shall not do [it]." And the explanation came about it (Chagigah 14b), "[To] all in your land you shall not do [it]" - meaning to say this shall not be done among Israel; or its explanation is from every species in your land you shall not do [it]. And "[to] all in your land you shall not do [it]" includes man and beast and all animals. And the content of the verse is not to say that there only be a prohibition of castration in the Land. And explicitly did they, may their memory be blessed, say in Shabbat 110b in the chapter [entitled] Shmoneh Sheratsim, "We learned, 'From where [do we know] about castration of a man, that it is forbidden? [Hence] we learn to say, "and in your land you shall not do [it]" - you shall not do it in (to) you.'"