Musa bin Talhah (may Allah have mercy on him) says that Sayyiduna Umar (may Allah be pleased with him) said to Abu Dharr, Ammar and Abu al-Darda' (may Allah be pleased with them): Do you remember when, at such-and-such a place, a Bedouin came to the Prophet (peace and blessings be upon him) with a hare and said: O Messenger of Allah, I have seen blood on it; and he (peace and blessings be upon him) ordered us to eat it and did not eat it himself? They answered in the affirmative. Then he (peace and blessings be upon him) said to the Bedouin: "Come close and eat." He said: I am fasting.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الضحايا / 19402