From Sahih Muslim (Hadith 4026):
Salim b. 'Abdullah reported on the authority of his father that Allah's Messenger (ﷺ) said:He who kept a dog other than one meant for watching the herd or for hunting would lose every day two qirat of his good deeds. 'Abdullah and Abu Huraira also said: Or dog meant for watching the field
Reference: Muslim 4026