(3) باب اقْتِنَاءِ الْكَلْبِ لِلْحَرْثِ
Narrated Abu Huraira:
Allah's Messenger (ﷺ) said, "Whoever keeps a dog, one Qirat of the reward of his good deeds is deducted daily, unless the dog is used for guarding a farm or cattle." Abu Huraira (in another narration) said from the Prophet, "unless it is used for guarding sheep or farms, or for hunting." Narrated Abu Hazim from Abu Huraira: The Prophet (ﷺ) said, "A dog for guarding cattle or for hunting."
Reference: Sahih al-Bukhari 2322
In-book reference: Book 41, Hadith 3
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 3, Book 39, Hadith 515