When I was young, we had a male English Shepherd which was very fast, with tremendous stamina, a cattle herder ( we had 300 head ). It could run about 50 mph for sustained half mile, so it would run down or marauding feral dog. In a big field, it would get between them and the woods, and cut them off, then close the circle until they had then in the middle of the field and totally tuckered out, then kill them. As you all know, different breeds of dogs are just wired up to do things, like a bird knowing how to build a nest.