Since the purpose of God’s creation is to add life to the world, it is forbidden to castrate animals. Castrating male animals is biblically prohibited. There is a disagreement about female castration, but the consensus is that it is rabbinically prohibited. When there is a need to contain the animal population, it is permitted, but only indirectly through hormonal treatments. If truly necessary, female animals may be rendered infertile, through shots or tubal ligation. However, direct removal of their reproductive organs should be avoided.
