Musnad Ahmad 948:0

Narrated Sufyan ibn Abi Zuhayr: I heard the Messenger of Allah (ﷺ) say: "Whoever keeps a dog, except a dog for herding livestock or a hunting dog, a qirat of his reward will be deducted every day." I said: "Did you hear this from the Messenger of Allah (ﷺ)?" He said: "Yes, by the Lord of this Mosque."