Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) says: When you send your trained dog with the name of Allah, you may eat the game whether the dog has eaten from it or not.
As for the report on this from Sayyiduna Sa'd bin Abi Waqqas (may Allah be pleased with him), Malik mentioned it from him in al-Muwatta' as munqati' (with a broken chain).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيد والذبائح / 18879