How do I teach a dog to roll out on another hog

I will have to disagree, it is not genetic it is Discipline, you have to get the dog attention. I don't main beating the dog but get the dogs attention. I have said this before, I teach my dogs three commands (Get Back) (Load Up) ( And the Call to Come Here) I start this as a pup.
Training, I use to have small hog pin about 50y by 100y, I would get about 3 or 4 hogs around 125lbs and have the dogs bay, I would go in with a catch dog and catch one, the dogs or pups would see the other pigs and would rather bay them than get hit buy the a 1" PVC pipe ( PVC works good because it is flexible not like wood). When the dogs leave to go bay the other pigs then turn the pig loose and start all over again.
Hope this helps.