I keep getting posts on Facebook about an American company that supplies nurse mares for orphan foals. The stories are very heartwarming given the tragedy that would have unfolded before the orphan met its new mum. However, not knowing anything about the subject I keep wondering it it’s a bit like bobby calves and that the mares have to have a foal of their own each year to keep the milk supply going. I’ve tried googling the subject but still haven’t worked out how it works in practice; one thing I read said that the mare had to be returned in foal and that teasers were used to enable this. So what happens to their foals?