While I would agree that Border Collies and other herding breeds can make good dogs for farm animal protection, remember also that the herding instinct is basically just a variation of their prey drive. I would definitely start with very young dogs and raise them around the animals you want them to protect. The Pyrs on the other hand are bred to guard and protect livestock that they are raised with. Yes some of them will roam, but there are lots of ways to limit that too.