Changes in behavior are important to note. They might be an early indication that something is wrong with your horse. His health could be failing because of an unbalanced diet or he might have developed an allergic reaction. He might have a lameness issue that is hard to detect or brought on by certain stimuli; for instance, your saddle might be pressing on a sore spot on his back. Your mare's ovaries, located just behind where you would sit on her, might be sore, which could indicate a variety of problems. Careful attention to how and when your horse is acting poorly will help you and your vet figure out the problem and correct it. Be careful not to discipline your horse for acting badly before you know if he is suffering from an underlying problem or has just a behavior problem.