The pig wolfs her food down. Is that where the pig/wolf connection comes from? Do wolves wolf pigs down? Or do they pig out on them? Anyway, the pig pigs out/wolfs down the food, so she has a piggy snack ball. It's a bit like a hamster exercise ball except that it's not filled with hamsters.
As Nala rolls the ball, snacks fall out of small holes and she snaffles them up. It keeps the wolf from the door between meals. Or maybe it entices the wolf, with the sounds of pig snuffling.