I had noticed that my new mare's hooves were growing in junky looking. I was a little concerned about it, but I figured different care, plus I had to pull her off grain. I put her on a hoof supplement. But today I noticed my other mare is having the same issue. I've had her for years without this problem. I haven't changed her feed in maybe 2 or 3 years. They both get different hays. And my stallion's feet are the same as they always were. The new mare gets regular work, the other mare does not. Any ideas what I can do to fix it?