With rare exceptions I don’t think foals should be weaned earlier than 5 months. If the mare is pregnant again, or unusually stressed then the foal may be weaned early. Otherwise I’d wait until 6 or 7 months. I have seen mustangs nursing yearlings and once I saw a mustang mare nursing both a new foal and a 2 year old.

I don’t believe in sudden complete separation of mare and foal. Keep them side-by-side in adjacent enclosures. Then, gradually separate them. On large farms with many foals, one mare may be removed each day. It is less stressful on the foal to have the company of other foals and their dams that way.

Once weaned the foal will need a properly compounded feed additive plus, of course, free choice forage. Ask your veterinarian to recommend the foal’s diet. Also ask when to vaccinate and worm in your area. Special supplements may also be recommended in some areas. It varies with the climate, available forage, and soil conditions.

Question: Should colts be started in a snaffle bit?
Answer: Skilled horsemen can do this, but it isn’t necessary. Any colt can be started in a halter or a hackamore, or, what I prefer, a side-pull. Then, later, a transition can be made to a bit.

Question: Is biotin necessary for a healthy hoof?
Answer: Yes, and the diet may provide enough, but it does no harm to supplement biotin and I have often observed improved hoof wall as a result of such supplementation.