It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever keeps a dog other than for hunting, guarding or farming, two qirats will be deducted from his reward every day." (b) Likewise Ibn Umar (may Allah be pleased with them both) narrates from the Prophet (peace and blessings be upon him): "(Two qirats)", but in most narrations he did not mention the guard dog.
Sayyiduna Abu Hurayrah (may Allah be pleased with him) and Sufyan bin Abi Zuhayr (may Allah be pleased with him) narrate it from the Prophet (peace and blessings be upon him), but Sufyan did not mention the hunting dog, and said: "One qirat."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 1184