tiago you obviously have no knowledge of the ab the ab is a utility breed and if raised with livestock they can work them and they would defo protect against predators. heres a video of a 5 mth old ab working sheep which will progress onto cattle when older. this dog is from performance bred ab's with a high prey and fight drive so i think she would be perfect for predator eradication http://www.youtube.com/watch?v=9NLKJG6oliU