Sayyiduna Adi bin Hatim (may Allah be pleased with him) asked the Prophet (peace and blessings be upon him) about hunting. He (peace and blessings be upon him) said: "When you send your dog, mention the name of Allah; then if you find that it has killed and has not eaten anything, then eat, for it held it back for you. And if you find that it has killed and eaten of it, then do not eat anything of it, for it held it back for itself. And if another dog joins your dog, and it kills (the game) and does not eat of it, still do not eat anything of it, for you only mentioned the name over your own dog; you did not mention the name over the other. And when you shoot an arrow, mention the name of Allah; then if you find that it fell into water and died, do not eat it, for you do not know whether the water killed it or your arrow. And if you find it after one or two nights and see no mark on it other than the mark of your arrow, then eat it if you wish."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14227