We gelded a horse at age 14 that had
been used sparingly for live cover breeding. He is very easy to handle and ride
with other horses. He has turned out to be the alpha gelding in our pasture,
even at age 19, but he doesn't bite or kick the other geldings. We have also
pastured him with mares (recently). He does tease mares in heat, but he has not
tried to mount or become aggressive and has never been a problem riding with
mares.
