I have two boars, Butterscotch and Espresso. A couple of times a day they will run around rumbling, chasing, humping (Butterscotch mainly), and butt sniffing. I know that this is normal behavior, but while they are doing this stuff they are popcorning and wheeking, just like they do when it's time for food. Is this how they play? It confuses me LOL. I am just a worried piggy mom, that doesn't want anybody to get hurt. Thanks!