question #3 Sahih al-Bukhari 3325, Book 59, Hadith 131 : What are the permissible reasons for keeping a dog in Islam?

That he heard Allah’s Messenger (ﷺ) saying, “If somebody keeps a dog that is neither used for farm work nor
for guarding the livestock, he will lose one Qirat (of the reward) of his good deeds everyday.”