Musannaf Ibn Abi Shayba 16:34

Abu Bakr narrated to us, he said: Ma'n ibn 'Isa narrated to us, from Ibn Abi Dhi'b, from al-Zuhri, who said: I asked him about the 'aqiqah. He said: "Its bones and its head are not to be broken, and the child is not to be touched with anything of its blood."