You put a lot of time, money, and care into your mares and foals, so as a horse breeder, you really want to do all you can to ensure your mares' and foals' health. In addition to a good diet and proper vet care, one thing you may want to consider is adding various herbal supplements to your mares' routines. Here are a few specific herbal supplements that tend to work well for broodmares and their foals.