If your horse is mannered enough to chew the food before swallowing it, a whole apple is fine. However, due to the risk of choking, it is recommended that you chop it in some way. You can also slice an apple, cut it into cubes, or grate it. Apple sauce is another option. If you’ve got extra time on your hands, add molasses and oats to grated apples to serve as a delicious treat.