It is narrated from Hazrat Abu Saeed Khudri (may Allah be pleased with him) that once I bought a ram for sacrifice. Coincidentally, a wolf came and bit off and ate a part of its haunch. I asked the Prophet (peace and blessings of Allah be upon him) (whether it could still be sacrificed or not?). The Prophet (peace and blessings of Allah be upon him) said: Sacrifice it as it is.