"مَنِ اتَّخَذَ كَلْباً, إِلَّا كَلْبَ مَاشِيَةٍ, أَوْ صَيْدٍ, أَوْ زَرْعٍ, اِنْتَقَصَ مِنْ أَجْرِهِ كُلَّ يَوْمٍ قِيرَاطٌ"
Abu Hurairah (RAA) narrated that the Messenger of Allah (ﷺ) said: 'If anyone owns a dog except a sheepdog, a hunting dog, or a farm dog, a carat of his reward will be deducted daily." Agreed upon.