Are there still rustlers out there? I've watched some old westerns where humans steal livestock, that stuff actually happen nowadays? Beware what you ask for wanting human aggressive dogs. Most farmers can't afford big fencing, those dogs are going to leave their properties and come after innocent people (like me) out on the road. If this dog bit me, the owner would be in a lot of trouble, maybe even go to jail. Perhaps it's liability that keeps the popularity of these dogs down.