I believe most of the "white" bulldogs my family had access to were of spanish decent. Lot of the spanish that settled here in Florida were cowman who brought and bred stockdogs of the alaunt "type". I believe these dogs to be more of a bulldog type than breed. Definitely believe the sheperd's mastiff/bulldog proper, to be in the mix. I believe these dogs to be completely seperate from pit bull dogs, as these dogs were bred to work, not fight.

Again, this is just my families "beliefs", but I will say this, the ones we've owned were "natural" stockdogs all by themselves.