What is the ruling on castrating animals for meat production, and what is the ruling on tattooing animal skin for tagging and identification?

The jurists differed on the ruling regarding castrating animals for meat. Some permitted it, citing the hadith of Aisha (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) sacrificed two castrated rams. Others disliked it or differentiated between young and old animals. Still others prohibited it absolutely, citing the hadith of Ibn Abbas that the Prophet (peace and blessings be upon him) severely prohibited castrating animals, and Allah's saying: (And I will surely command them, and they will alter the creation of Allah).

As for branding an animal to distinguish some from others, if it is on the face, it is forbidden because the Prophet (peace and blessings be upon him) forbade striking the face and branding it. If it is not on the face, it is permissible for a legitimate purpose, and it is recommended that the branding be in places that minimize pain and make the mark visible, such as the ears of sheep and the thighs of camels and cattle.