Also, Brother Justwanttolearn,
As to your concern about your black dog. I once spent quite a bit of time researching this issue.
It seems no one actually knows why black dogs were singled out. But many people believe that it was referring to black hyenas that lived on the outskirts of the village during that time period. While others suggest the culprit was the wild African dog. Either one of these animal would have neen a danger to both humans and livestock.
Another possibility for the ban on dogs was the fear of rabies infected dogs wandering throughout the town. Thus by listing what dogs could be owned based of their usefulness to the owners and the community. Which in effect, de facto mandated that all dogs must have a responsible and identifiable owner.
Thus all stray dogs that obviously threatened the citizens safety could be disposed of.