Hadith 510580
Chapter 25: Game - كتاب الصيد
وَحَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ كَانَ يَقُولُ فِي الْكَلْبِ الْمُعَلَّمِ كُلْ مَا أَمْسَكَ عَلَيْكَ إِنْ قَتَلَ وَإِنْ لَمْ يَقْتُلْ .
Yahya related to me from Malik from Nafi that Abdullah ibn Umar said about a trained dog, "Eat whatever it catches for you whether it eats from it or not."
Reference Muwatta Malik 510580
USC-MSA web (English) reference : Book 25, Hadith 5