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No matter how closely you observe your miniature horse, some indoor accidents will occur during this training process. If you simply can't cope with cleaning up feces or urine inside your home, don't attempt to keep a miniature horse as an indoor pet.
You may be tempted to bring your miniature horse with you into public places once he is house-trained. This is acceptable in some places, such as most chain pet stores and many public parks, but you always should call ahead for permission when planning a day trip with your miniature horse.
Once your miniature horse has learned to relieve himself only outdoors, try teaching him to ring a bell when he needs to go out. This can be accomplished by hanging a bell by the door and ringing it as you pass through the doorway each time you take him outdoors for a break. Your horse will soon learn that the bell signifies a break and will ring it to summon you.
If you can't get up during the night to take your miniature horse outside, consider keeping him outdoors at night and bringing him in only during the day.
When using treats for training, prevent obesity by reducing your miniature horse's daily hay and grain ration by approximately as many calories as he consumes in treats each day.
Miniature horses can be house-trained with positive reinforcement and dedication. Potty training a miniature horse is a project best suited to experienced trainers who don't mind cleaning up a few messes along the way. A fully house-trained miniature horse can delay elimination for up to six hours, according to the Guide Horse Foundation.
Potty Training a Miniature Horse
Teach your miniature horse to expect a treat when he hears a click from your clicker. This can be accomplished by clicking the clicker and offering a treat immediately after the click. Repeat this until your horse immediately looks for a treat when he hears a click.
Click and give a treat to your miniature horse each time he relieves himself. During this part of the training process, you will need to observe your horse for as many hours as possible each day. Most miniature horses will eliminate only once every three to four hours, giving you few opportunities to reinforce this behavior. You may need an assistant to watch your miniature horse when you can't be present and reinforce him for eliminating.
Introduce a cue. Each time your miniature horse eliminates, use a distinctive signal to acknowledge the behavior before clicking and treating your horse. The cue can be a whistle, a word, a hand gesture or anything else the horse can easily differentiate from normal sights and sounds.
Reward your miniature horse for relieving himself only after you've given your chosen cue. This is called "tightening your criteria for reinforcement." Set your miniature horse up for success by giving your elimination cue at times and in situations where he usually relieves himself.
Bring your miniature horse indoors. At this stage, your miniature horse should never be out of a human's sight. You will need an assistant to help you watch the horse constantly. If he shows any signs of needing to eliminate, like raising his tail or stretching to urinate, he should be taken outside, given his elimination cue and rewarded for eliminating outdoors.
Reinforce outdoor elimination on cue and ignore any indoor elimination behavior. Continue to take your miniature horse outdoors immediately if he shows signs of eliminating in the house. Over a period of several weeks, your horse will learn to wait to relieve himself until you take him out for a bathroom break. Remember, he can't "hold it" for longer than five to six hours.