Pig dogs can be bred from breeds as diverse as Deerhounds and Greyhounds, Dalmatians, Pointers, Great Danes, not to mention Mastiffs, Staffords and APBTs etc etc. The list is vast. Yet I can't think of anyone that would look at a German Shorthaired Pointer and automatically think of it as a killer dog. But this thought is common with a Pit??
Dogs become killers bacause they are treated and trained and even bred to it. It is irrespective of breed or type.
Lets not forget that all dogs are carnivores. They are hunters. Even Chihuahuas, even Poodles.