Question

I have a pair of sows, one of them is long haired and she has a porcupine like tuft of fluff that sticks out of her back end that I call her butt fluffs. The other, she's smooth coated. I've noticed that my smooth coated piggy loses a lot of fluff from her butt area, it releases super easy like I just have to touch it and it comes out in tufts, but this doesn't happen to my fluff ball. My fluffy ball is the more dominant pig. My question is, or rather questions are - is this normal? Could it be hormonal because they've just turned 5 months? Or should I get her checked out for it?