Dang, now one of her front ones is affected. Hosing didn't seem to do anything. The hind ones have heat, the front one does not, but it's not as bad as the hinds. They feel fluid filled and she pulls away when I apply pressure to the swollen areas. I've never seen anything like this before and although she doesn't limp or noticably favor any one leg, her movement is definitely affected. Ugh, I'm not going to sleep well tonight.
FehrGround, no scratches.
Macabre, the two horses are on about 3 acres of pasture (two equally divided pastures) normally, but since Wednesday they've been confined to one side as we're having work done in the other pasture. I don't know if an acre and a half is considered a small space. Very little dirt and no mud. Now, I did look in my equine veterinary manual and found a condition simply called "fluid filled legs" brought on by lack of exercise. It's only been a week since I've ridden her and there have been longer periods of time so I just don't know.
Thanks for the replies!