Sayyiduna Adi (may Allah be pleased with him) asked the Messenger of Allah (peace and blessings be upon him): We are people who hunt with dogs. He (peace and blessings be upon him) said: "When you send your trained dog with the name of Allah, if the dog holds the game for you, then eat; if the dog kills the game and eats something from it, then do not eat the game, for it may have hunted for itself; and if other dogs join it, then too do not eat."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيد والذبائح / 18876