is my mare in heat or pregnant?

Question
while grooming I discovered that one mare has more black waxy stuff between her teats than our other mare and she also has white crusty stuff on the ends of her teats.
She is almost 3 years old, and was neglected before I purchased her, so of course I'm concerned.

Answer
Dear Angel,
         Let me say i have experiance breeding horses, and sometimes you need to clean out that area. Before and after breeding. But once a week geldings, mares, and stallions need there external reproductive organs cleaned thoroughly. It is possible that she is pregnant but if she was neglected that could also be the case, but if she was it would not be crusty or as the other mare black. Clean the area with a soft sponge and gentle soap once a week, they may not take it well so be carefull.
michelyn