One pup on the ground at the time.
I agree if you're in the woods on a real hunt... But we run mock hunts with all the pups and no vet dogs around. Do some drags and ties, and after they start using their nose pretty good just cut the pig loose and give it a little head start. They will figure it out after a few times, and if they don't start turning on then you may have some culls on your hands.
But the main thing that I have figured out being around and seeing pups turn on is that you have to wait long enough for them to mature enough to do so. JMO
