I believe dog to dog aggression to be bred for is as simple as breeding dog aggressive dogs together, but that does not mean that all those dogs will fight. (btoellner.typepad.com)
It can also cause other problems because in many cases these quick fixes are not permanent and in some cases can make dogs aggressive. (thehappypuppysite.com)
I have not said that they are not dog aggressive, because no one is talking about that aspect of them. (btoellner.typepad.com)