Hello,

For a mare that's been used as a surrogate, you are able to put them up for breeding again on the barn/pasture mass public breeding page. Even though they've had a surrogate foal during the current game year they're still showing up in the search as unbred. Other users will get an error when trying to breed with them.

I've just been able to put a mare up for breeding that was used as a surrogate earlier this month. I did it from the "public brood" view in barns, and all surrogate mares showed up and now show as available for breeding to other stables