Suppose you’re an average wild horse, a herd animal that spends eight to ten hours a day grazing. You play and frolic with other horses, groom each other, perhaps compete with another horse to establish hierarchy.

Now you’re taken out of your natural environment, confined in a stall, given two feedings a day and prevented from the activities that instinct and evolution compel you to do. This condition leads to stress and the chance you will engage in abnormal compulsive behavior.

Compulsive behavior in horses is called stereotypy, a type of repetitive behavior similar to the human diagnosis of obsessive-compulsive disorder. These activities have no apparent purpose and consume much of the animal’s time. About 15 percent of stabled horses perform some type of stereotypy.

Types of compulsive behavior

Cribbing – A common behavior in which a horse braces his upper teeth on a surface, arches his neck, inhales a large gulp of air and then releases it in a sort of belch.

Wood-chewing – The nibbling of wooden parts of a horse’s stall or fence.

Lip flapping and tonguing – Smacking lips together or constantly licking, and the moving of the tongue from back to front.

Stall-walking – Pacing the stall either from side to side or in a circular motion around the interior of the stall.

Weaving – Rocking back and forth in place from one foot to another in the stall or against the walls.

Head bobbing – Bobbing or nodding the head up and down, or weaving side to side.

Self-mutilation – Repeatedly biting the hind quarters, a leg or sides, or kicking itself.

Causes of compulsive behavior

Confinement and isolation – Being kept from the company of other horses is very stressful. Horses like the company of their human companions, too. Some compulsive behavior occurs when people are present because the horse wants attention or when people are absent because the horse experiences separation anxiety.

Inactivity and boredom – Along with isolation, lack of activity or exercise can create boredom; the horse will then perform compulsive actions to pass the time. Behaviors such as cribbing, stall-walking and weaving release endorphins that stimulate the pleasure centers in the brain.

Quality of food – High-concentrate feed may contribute to cribbing activity because it increases production of stomach acid. In addition, low fiber feed may enhance compulsive activities.

Genetics – The probability of a horse developing compulsive behaviors increases in certain genetic lines.

Relieving or preventing compulsive behavior

With horses, as with people, you can prevent the behavior with confinement or restraints (such as a cribbing collar), but you are not curing the underlying need to perform the compulsive behavior. It is more efficient to determine the cause and then eliminate it.

Pasture time and socialization – Give the horse more grazing time in a pasture of sufficient size with other horses so he can socialize, perform the natural act of grazing and increase the amount of forage in his diet.

Feedings – Because twice-a-day feedings are not a natural schedule for horses, try feeding smaller portions of various types of hay along with carrots up to six times daily. Ensure the horse’s diet has adequate fiber.

Exercise – Provide the horse structured and stimulating exercise, training and riding. But don’t overdo it, as training that is too strenuous or complicated may lead to frustration and stress.

Never punish – Punishing a horse is not effective because the horse does not associate punishment with behavior, and punishment may exacerbate the behavior.