We had a Appaloosa filly sewed up like that. When she came in heat for the first time, her bladder stuck out the vulva. They left just enough of a gap for urinating. Yes, it is more common in Thorougbreds mares. We did not keep this "gappy Appy".
Is the fact that it is more common on Throughbreds have to do with racing? do you know. I was just wondering because alot of barrel horses are sewed up. I wondered if the more then normal amount of running they do has to do with why they develop the problem that causes them to have to be sewed.
Becky