I don't own a horse, but I've heard that Simply Equine supplements are amazing! Its a hair analysis, so you send off some hair from your horse, and the Simply Equine company analyses it, works out what areas your horse needs extra help in and sends back bags of supplements that assist in behaviour, appearance and others depending on what your horse needs :) Good luck!

We feed all our horses EquiShine Mineral, which great for overall health. Keeps their hair coat really nice and healthy, and is good for developing younger horses, as well as up keep for aging horses. We also have them all on Fastrack, which is just a digestive supplement. Keeps their guts happy, and we seem to have less colics since putting everyone on it. Then we give MSM and/or Cosequin to our older horses who need that extra attention for their joints and stuff (our old stud has Arthritis, ringbone and a blown out knee), as well as our show horses who have pretty heavy workout programs. Then we have an old stud who gets NUImage, which is really good for keeping hair coats sleek and seems to keep his energy levels up. And our younger stud is also on Remission, which is for horses who are prone to founder/have foundered (he foundered last year). Both studs get MSM and Cosequin. We occasionally give Rice Bran to our older horses when we want to put more weight on them as well.