I'm a little late on this one, but oh well.
Hogs, especially western or plains, will soak occasionally. My femals 100%het albino does it all the time, not to retain moisture, but she does it for fun. I can always tell when she wants to come out and play because she'll climb, move around alot, torment my bearded dragons (which are in a cage next to her. They think she's a gian mealworm), or soak. It happens, it's normal, as long as they don't drown!

Peanut Butter Jelly Time!