Horses tower over dogs. They are large animals, so it's natural for dogs to feel dominated or intimidated. They express their fear through barking -- a natural form of communication. Dogs pick up their owner's emotions as well. If the owner feels frustrated or irritated because of the constant barking, the dog interprets the owner's emotions as trouble. In other words, the dog desires to protect its owner from danger or -- in this case -- the horse.
Set boundaries. Use a five-foot leash and a secure collar -- such as a prong collar -- to establish boundaries. Walk your dog about 20 feet away from the horse, as if you were on a routine stroll. Tug the leash calmly, but firmly when the dog begins to show any sign of anxiety.
Close the boundary to 10 feet once your dog shows proper leash etiquette. Lead the dog; make sure it does not lead you.
Let go of the leash. Use commands such as "sit" and "stay." Remain close to your dog in the event it tries to run toward the horse. Step on the leash if your dog makes any sudden movements. Maintain a calm and assertive demeanour.
Correct the behaviour. Remain within the 20-foot boundary. Jerk the leash to the side at the first sign of whining or anxiousness around the horse. Do not allow your dog to begin barking.
Stay calm. Do not yell at your dog or visibly show frustration. Maintain a calm stance and dominant demeanour.
Give sharp commands. Speak an assertive "No" or "Stop." Decide on a vocal command and consistently use it. Do not say "stop" one day and "no" another.
Run laps. Run your dog around with the leash while maintaining the 20-foot boundary. Tire your dog out to more easily control it during the training process. Start using the 10-foot boundary to test your dog's behaviour when closer to the horse once the dog calms down and no longer pays attention to it.
Get a professional trainer. Both the horse and the dog intimidate each other. The horse, however, can do more damage. It can injure you or your dog when spooked. If barking becomes a major problem, seek professional help to avoid dangerous situations with your horse. Use caution with prong or pinch collars. Make sure you know how to properly use them before making them part of your training sessions. While barking signals fear, it could also mean your dog has a lot of unused energy. Find ways to tire it out, which helps to alleviate anxious or excited behaviour. Spend a week or two working on proper leash etiquette with your dog. This will help you to gain control. Leash etiquette means your dog knows how to heel, walk on your left side and not pull you during walks.
A barking dog could spook or scare a horse, causing unpredictable behaviour such as kicking. A fearful horse poses a serious threat to everyone in close contact with it. A horse can injure or even kill an out-of-control dog. Use the leash at all times until your dog can be trusted. Keep in mind that this training requires weeks -- possibly months -- of consistency and patience.