If the anatomy of the horse (and seems to happen alot with TBs - and frequently with really skinny horses) is such that the anus is "sunk in" and the vaginal opening is underneath and at such an angle that when the horse poops, it consistantly gets into the vagina and can cause problems .. pg or not.
A mare can do most anything with Caslicks in place EXCEPT natural cover and foaling... would be a bad deal either way.
If she has no udder development, then there shouldn't be an urgency, but I would have to know. I'm not really sure how they would be able to tell, unless they removed the sutures and palpated .. hmmmmmmmm.
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