Article: A veterinarian or horse feed seller may be able to advise you on a healthier brand of bagged grain, and/or a less fattening hay. If your horse is overweight, or if its ribs are showing, consult a veterinarian for advice on the horse's feeding schedule.  Keep in mind that a working (or exercising) horse needs more food than one that stays in a stall or pasture all day. Do not give the horse diet or medical supplements without the advice of a veterinarian. If you feed your horse treats, cut back or switch to healthy alternatives. Carrots are healthy treats, while sugar cubes are not. Let the horse into a pasture for at least three hours a day, and preferably for six hours or longer. Roaming and grazing in an open space may boost the horse's energy level, reduce negative attitude, and even help its digestion and injury recovery speed.

What is a summary?
Adjust the food type and amount. Minimize unhealthy treats. Let the horse out of its stall.