كتاب الصيد والذبائح
Read the English translation first, with the original Arabic directly underneath.
It was narrated from 'Abdullah bin Mughaffal that the Messenger of Allah said:
"Were it not that dogs form one of the communities (or nations - of creatures), I would have commanded that they be killed. But kill those that are all black. Any people who keep a dog, except for dogs used for farming, hunting or herding livestock, one Qirat will be deducted from their reward each day."
لَوْلاَ أَنَّ الْكِلاَبَ أُمَّةٌ مِنَ الأُمَمِ لأَمَرْتُ بِقَتْلِهَا فَاقْتُلُوا مِنْهَا الأَسْوَدَ الْبَهِيمَ وَأَيُّمَا قَوْمٍ اتَّخَذُوا كَلْبًا لَيْسَ بِكَلْبِ حَرْثٍ أَوْ صَيْدٍ أَوْ مَاشِيَةٍ فَإِنَّهُ يَنْقُصُ مِنْ أَجْرِهِ كُلَّ يَوْمٍ قِيرَاطٌ