So I have a bunny, I'm not too sure of his breed, he's a Californian mix of some sort. Anyways, the past couple of months I've noticed that he lets his bottom get very dirty. It is matted poop, and I have to carefully cut it off. It doesn't take very long for it to get matted back in. I have even trimmed his hair down there hoping that it would help but nothing has helped. He's a super laid back bunny and has never really enjoyed playing with toys unless it was throwing something. So should I take him to the vet, or change his diet? I have another bunny on addition with him. So between them they get 1/4 cup of a pellet mix and 2 tablespoons of an extra feed that's supposed to help with coats and additional health related stuff. They get the usual fresh hay. I also get them fresh greens at least once every other day or so. The other bunny hasn't had any problems cleaning and is always pristine. Any opinions on what I should do? Thanks!