Sayyiduna Salman al-Farisi (may Allah be pleased with him) says: When you send your trained dog after game, and it eats two-thirds of the game and only one-third remains, you may eat what remains. (b) Qatadah narrates from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that he disliked this and used to say: If the dog were trained, it would not have eaten. And the permissibility of eating it has been narrated from the Prophet (peace and blessings be upon him), if the hadith is authentic.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيد والذبائح / 18882