There he goes again. Your horse is pawing incessantly at his stall floor, or he's cribbing, emitting a stream of rhythmic grunts as he pulls on the door with his teeth. You've tried repeatedly to get him to stop, but the behavior persists.
Why is he doing this, and how can you get him to quit?
For years, we've called behaviors like these stall or stable "vices." The first part of the name is right with the exception of fence-walking, a horse doesn't do these things unless he's in a stall. But the "vice" part isn't correct, according to modern research, which indicates these actually aren't bad habits per se, but simply the reactions of horses that aren't getting what they need.
And what's that? A more natural environment, unavailable largely because of stable management practices that go against an equine's basic needs.
Researchers have discovered that many of these behaviors typically develop early in a horse's life, so your horse may have already had one when you bought him. But even if your horse is older, you can generally reduce and sometimes eliminate an unwanted behavior by addressing its cause, not its symptom.
I'm going to describe the behaviors in question, outline the traditional ways of treating them, then give you the latest thinking on ways of dealing with them that are more humane, and often more effective. (And even if your horse doesn't have any of the behaviors, the back-to-nature approaches to management I'll give you will assure he doesn't develop any plus improve his overall quality of life.)
Vices? No, Coping Strategies
Stall vices are more accurately called stereotypic behaviors, that is, repetitive, apparently functionless behaviors that fall into two categories. These are locomotor (which include stall- and fence-walking, weaving, pawing, stall-kicking, and head-bobbing) and oral (cribbing, wind- sucking, wood-chewing, and tongue-lolling).
Stereotypic behaviors have never been observed in horses who live as Mother Nature intended outdoors in a herd, grazing or foraging 40 to 60 percent of the time.
By contrast, five to 10 percent of domestic horses develop them.
Which ones? Studies indicate horses with limited social interaction and turnout, inadequate roughage (such as hay and/or pasture), and large, infrequent grain meals (two to three per day, rather than having roughage always available) are much more prone to develop the habits that have traditionally been called vices.
Let's take a closer look at each of the two categories of equine stereotypic behaviors.
Gotta Move: Locomotor Behaviors
In the list below, you'll learn what these behaviors look like, when they typically start, what specifically causes them, and what we used to do about them. Then, in the box "Slowing the Locomotion" (page 3), I'll give you the latest thinking on how to deal with all of these "gotta move" behaviors.
Stall- and fence-walking
What it is: Rapid walking (pacing) inside a stall or along a fence.
When it starts: At about 18 months or older.
Causes: Anticipation of a meal and/or a need for equine companionship. Feeding large, infrequent grain meals and inadequate roughage can upset a horse's digestion, and also creates long periods between meals, which can result in a hungry, lonely, and/or frustrated horse that intensely anticipates his next feeding. Because horses are herd animals, they feel most content and secure when surrounded by other, familiar horses. Enclosing them in a stall or paddock can make them feel isolated from the herd. The resulting frustration causes them to attempt "escape" by resorting to stall- and fence-walking (or weaving).
Harm to horse: Possible chronic injuries (joint wear, tendon strains, muscle damage) that can lead to lameness; fatigue (a horse can wear himself out before he's ridden or performs).
Harm to the environment: Damaged stall flooring from constant movement; trenches along fence edges.
Old "cure": Make a horse wait to be fed to "teach" him patience. (This just intensifies the behavior.) Give him stall toys. (They typically don't work because they don't address what the horse is craving. He's not bored?he wants to escape so he can be with other horses.) Tie him up. (This stops the movement, but you'll likely wind up trading one stereotypic behavior for another, as a tied horse will often begin to weave.)
What it is: Walking in place, picking up both the hind and front feet, usually at the opening to a stall.
When it starts: Usually when a horse is first confined for any length of time.
Causes: Same as for stall- and fence- walking.
Harm to horse: Chronic weavers can actually wear their bare feet down to the point that their soles bleed. Other possible effects include chronic injuries (joint wear, tendon strains, muscle damage) that can lead to lameness, and fatigue.
Harm to the environment: Damaged stall flooring.
Old "cure": Same as for stall- and fence- walking.
What it is: Repeated digging into the ground, usually at the opening to a stall.
When it starts: No common age known.
Causes: Frustration while waiting for food. When a stabled horse expects a grain meal, he may paw the ground as he would while foraging in the wild for food under snow or for water in a dried-up pond. In a stall, because he receives the food after he paws, he starts to believe that his pawing caused the food to appear. Pawing has also been associated with a need for companionship, so it may also indicate an effort to escape.
Harm to horse: Increased hoof and shoe wear; fatigue.
Harm to environment: Damaged stall flooring.
Old "cure": Same as for stall- and fence-walking.
Head-bobbing, stall kicking
What it is: Repetitively moving head up and down or kicking at stall walls.
When it starts: At about 18 months or older, or when a horse is first confined to a stall.
Causes: Same as for stall- and fence- walking and weaving. (Note: Horses may also kick walls to threaten their neighbors. This type of wall-kicking is not considered to be a stereotypic behavior. Similarly, head-shaking under saddle is not the same as head-bobbing. Head-shaking is usually caused by a medical condition that should be checked by a vet.)
Harm to horse: Fatigue, and in stall-kicking, possible injury (joint wear, tendon strains, muscle damage) that can lead to lameness, as well as damage to hooves and shoes.
Harm to environment: Damage to stall walls (wall-kicking).
Old "cure": Same as for stall- and fence-walking.
Busy Mouths: Oral Behaviors
As their name implies, oral behaviors involve a horse's mouth, teeth, and/or tongue. In the list below, we'll discuss each of the oral behaviors, including specific causes, old-thinking "cures," and the modern approach to management.
Cribbing and wind-sucking
What it is: Cribbing occurs when a horse braces his top teeth against a fixed object, then flexes his neck as he draws air into his throat and grunts. Wind-sucking is similar, except the horse doesn't grasp any object with his teeth before sucking in air.
When it starts: At weaning, or when a horse begins to be routinely put in a stall and fed grain.
Causes: We're still not absolutely sure, apart from the basics of stall confinement, sweet feed, and lack of adequate roughage. Some researchers initially suspected that horses crib and wind-suck to reduce intestinal acidity caused by high-concentrate (sweet feed) diets. They thought these behaviors may increase the production of saliva, which could then act as a natural antacid, thus relieving digestive upsets and ulcers.
More recent research, however, has found that cribbing and wind-sucking don't promote salivation, although they do stimulate the production of stomach acid, which can lead to ulcers.
Cribbing and wind-sucking both tend to occur during or immediately after a grain meal containing molasses, and researchers have established a clear connection between cribbing and sweet feed (although feeding a horse plain oats and molasses doesn't appear to stimulate cribbing). Foals fed sweet feed at weaning are much more likely to develop a cribbing habit.
Alfalfa also seems to promote cribbing; otherwise, horses seem to crib less when eating hay only.
A longtime popular myth is that horses crib because they get a physiological "high" from the release of endorphins. In fact, studies have shown that endorphin levels in a horse's bloodstream actually drop when he begins to crib.
Harm to horse: Possible development or exacerbation of ulcers; wear to the upper front teeth; hypertrophy, or overdevelopment, of the neck muscles. Cribbing can also result in a rare form of colic called epiploeic foramen entrapment, which occurs when the cecum fills with air, floats out of position, and becomes stuck. This type of colic, though rare in all horses, is somewhat more common in cribbers.
Harm to environment: Pulling buckets and fence rails loose. (While cribbers rarely ingest wood, some do gnaw at wood surfaces.)
Old "cure": Cribbing straps or muzzles; surgery in which a nerve or muscles in the neck are cut; distasteful compounds painted on wood surfaces.
New approach: Feed plain oats and grass hay, avoiding sweet feeds and alfalfa if possible. Free-choice grass hay is ideal; it keeps your horse busy and helps neutralize the stomach acid that flows constantly to the equine stomach. Add supplements if need be to replace the vitamins and minerals your horse was getting in his concentrated feed. Check with your vet about ulcer prevention/treatment; he or she may recommend you add an equine antacid to your cribber's diet.
Provide as much turnout as possible, ideally on pasture with other equines.
Resort to a cribbing strap or muzzle only if your horse has had a previous gas colic, or is in poor condition from cribbing to the exclusion of eating. Both devices can rub away hair around the face and throat, causing pain and irritation. Because cribbing straps must be adjusted tightly to be effective, they can also cause painful tissue damage. So use either device with care, and be sure to accompany it with the other management strategies outlined above.
What it is: Gnawing at wood surfaces and breaking off pieces of wood.
When it starts: At 1 year or older; tends to occur seasonally, usually in late winter.
Causes: Wood-chewing may be less of a true stereotypic behavior because it seems to fulfill a purpose satisfying some horses' natural need to supplement their diet with "browse," vegetation such as leaves and twigs. Horses who do it seem to have a real craving for wood. (In the wild, horses may have turned to eating the tender shoots of trees to survive when grass became scarce in late winter.) When a horse doesn't have multiple sources of roughage, he may be prompted to chew on whatever wood he can find in his environment, including fences, walls, and doors. Wood-chewing may also be a learned behavior (see "Genetic or Learned?").
Harm to horse: Excessive tooth wear and, rarely, splinters in the gums.
Harm to environment: Destruction of wooden structures.
Old "cure": Painting distasteful compounds on wood surfaces. New approach: Greater access to pasture, and adding more types of roughage to the diet. Specifically, try offering your horse nontoxic branches and twigs (check with your vet or county agricultural extension agent first to find out which local species of trees and bushes are safe to feed). Painting "non-chew" compounds on wood surfaces may also help.
What it is: A protruding tongue, which may hang loosely or move about.
When it starts: Unknown.
Causes: Anticipation (as of feed) and a need for equine companionship, exacerbated by a low-roughage diet; large, infrequent meals; and/or limited turnout. Be sure also to have your vet rule out any medical causes, such as tooth and mouth problems.
Harm to horse: None, although it's frowned upon in most Western disciplines and may compromise a show career.
Harm to environment: None.
Old "cure": None, although nosebands and tongue ties (devices to hold the tongue in place; illegal in competition) have been used for horses that exhibit the behavior when ridden.
New approach: Greater access to pasture, more turnout and equine companionship, and adding more types of roughage to the diet.
Slowing the Locomotion
Because most locomotor behaviors result from anticipation (of a meal or turnout) and/or a need for more equine companionship, modern remedies focus on eliminating causes, rather than administering corrections. If your horse exhibits one or more of the locomotor behaviors, implement as many of the following management strategies as possible:
Increase his turnout. Ideally, place him on pasture with other horses. (Note: It doesn't seem to help if a stall-walker is turned out in a paddock that doesn't have grass, where he may switch from stall-walking to fence-walking.)
Hang mirrors on stall walls. Studies have shown that when a horse sees his reflection, he often feels less alone. For safety, mirrors must be either plastic or polished metal, or protected with bars.
Increase his roughage. Provide more hay, pasture, haylage, or hay cubes, divided into as many feedings as practicable. If your horse must be stalled, divvy up his hay rations among several nets to make access harder, thereby prolonging the meal. If you feed hay on the ground (ideally on mats to avoid the ingestion of dirt or sand), divide it into several small piles so your horse must move from one pile to another, as if grazing.
Consider an animal-activated, rolling food dispenser that your horse can nose around and nibble from, to simulate grazing. (Note: Don't use a dispenser on sandy soil, which could cause your horse to ingest sand.)
Use straw bedding. Horses stabled on non-straw bedding are more likely to display stereotypic behaviors, possibly because straw can serve as roughage. (Eating straw won't make a horse fat, although he may temporarily appear larger because straw can fill up his large intestine. Rarely, a horse may eat so much straw that it causes a blockage in his digestive system, which results in colic, so watch him at first to make sure he's not gorging on it.)
Widen his vistas. Open windows or doors on as many sides of your horse's stall as possible, or add more windows. Enabling him to see outside in all directions produces the best results.
Genetic or Learned?
Studies have shown that some stereotypic behaviors are more common in horses that compete in certain disciplines. For example, stall-walking is more common in endurance horses than in racehorses and some show horses. On the other hand, endurance horses seem more likely to crib than horses that race or show.
This suggests there may be a genetic tendency for stall-walking in Arabians (because most endurance horses are Arabians or Arabian crosses), although differences in stable-management techniques used in endurance and race or show barns may also play a role.
A recent study suggests that the three groups of horses at greatest risk for cribbing are Quarter Horses, Thoroughbreds, and a group that is a mixture of American breeds (Appaloosas, Tennessee Walking Horses, Morgans, and American Saddlebreds).
It's unlikely that horses learn stereotypic behaviors from each other. If several horses in the same barn develop the same behavior, they're probably reacting to that barn's stable management?and possibly to a genetic tendency for the behavior?than imitating each other. The one exception is wood-chewing, which research suggests may be learned.
Dr. Katherine Houpt
Dr. Katherine Houpt, VMD, PhD, DIPL, ACVB is the James Law Professor of Animal Behavior at Cornell University's College of Veterinary Medicine. She also oversees the school's Animal Behavior Clinic, where she treats a wide variety of problems, including cribbing and aggression. Board-certified by the American College of Veterinary Behaviorists, Dr. Houpt is the author of numerous scientific articles and the textbook, Domestic Animal Behavior.