Musnad Ahmad 623:5

Aswad ibn Amir narrated to us, Sharik narrated to us, from Layth, from Shahr ibn Hawshab, from Amr al-Thumali, who said: The Prophet, peace and blessings of Allah be upon him, sent with my father some sacrificial animals (hady). He said: "If any of them becomes incapacitated (near death), slaughter it, then strike its hoof in its blood, then strike its side with it, and do not eat from it, neither you nor the people of your company, and leave it between it and the people."