The Latest Word on Cribber Management

What research tells us about cribbing

Whether cribbing results in an endorphin "high," as thought by some, is similar to obsessive-compulsive behavior in humans, or is due to other factors, researchers are beginning to address the issue with increasing confidence.

What we do know is that once a horse develops a history of cribbing, it is nearly impossible to eliminate this behavior, which can lead to worn teeth, weight loss, colic, and a general decline in body condition. In addition, cribbing leads to destruction of fence posts, stable equipment, fences, and other property and can become rather costly over time.

Horse cribbing on fence

Horses that crib develop "favorite" cribbing spots that they frequent. New window.

When a horse cribs, it grasps a surface with the incisor teeth, flexes the neck, and swallows air. As the air passes through the throat, it makes a gasping, grunting, or groaning sound.

The root causes of cribbing appear to be complex. Human management during the early weeks of a foal's life, along with genetics, personality,  the presence of ulcers, and diet are thought by many researchers to be among the reasons horses turn to cribbing behavior. Also related to high incidence of cribbing is the breed of the horse, with thoroughbreds and quarter horses being at the top of the list.

Cribbing behaviors usually begin by 20 weeks of age, which is the age when weaning takes place. Changes in the environment, with the foal being away from its mother more, introduction of new feed types and feeding routines, and increases in stress are variables that require special attention to prevent the development of cribbing behavior.

Dr. Daniel Mills, a well-known equine behaviorist who has devoted much time to studying the development of stereotypies, including cribbing, has reached the conclusion that special care in the weaning of horses, including gradual weaning, a large amount of turnout time, and the feeding of a high fiber diet of hay or oats instead of concentrates, can reduce the number of horses that become cribbers.

Dr. Mills also notes that horses that are naturally anxious and stress-prone seem to have a predisposition for cribbing behavior, while draft-breed horses and ponies with more docile natures appear to be less apt to become cribbers.

Several researchers have found an association between gastric ulcers and cribbing, which indicates that horses with a lower gastric pH may be more prone to be cribbers. Treating cribbing horses with antacids has been found to significantly reduce the behavior. Dr. Katherine A. Houpt, Director of Cornell University's Animal Behavior Clinic, is currently testing whether a nontherapeutic antibiotic, virginiamycin, which inhibits acid-producing bacteria in the horse's large intestine, works to deter horses from cribbing.

Current management practices for horses that crib include diets that are high in fat and include more forage, while using less sweet feed. Most researchers agree that regular turnouts and diets that are high in forage and oats can reduce the frequency of cribbing.

Researchers are currently in disagreement over the idea that a horse receives a physical or mental benefit from cribbing. Some researchers indicate that horses provided with a rich environment with mirrors and toys in the stall and plenty of exercise are less likely to be cribbers, but others maintain that their studies don't show boredom to be a factor in cribbing behavior.

Some horses seem to have personalities that lead to obsessive-compulsive behaviors, much like humans who constantly wash their hands.

Research into how endorphin levels in the brain relate to cribbing behavior has not yielded consistent results. These "feel-good" chemicals in the bloodstream may or may not result in a "high" for the horse. In fact, according to Dr. Houpt, endorphin levels may be affected by other factors, such as the type of feed, which in turn might be the cause of the cribbing action.

Most researchers are in agreement that horses don't learn to crib from each other. In most cases, horses that have been observed cribbing after watching other horses have been shown to have an inherited, genetic predisposition to cribbing. In fact, evidence points to a genetic link in most thoroughbreds and quarter horses that crib.

So, what are the most effective ways to prevent or discourage cribbing?

1. Management of foal weaning practices: Wean foals gradually, give plenty of turnout time, and minimize use of feed concentrates.
2. Stable management: Let the horse out of the stall and back on the pasture with other horses as much as possible.
3. Feed: Give the horse plenty of free choice hay or forage, along with oats and very little or no sweet feed. For high energy, feed more fat.
4. Antacids: If cribbing is related to colic or ulcers, provide an antacid as part of the diet.
5. Cribbing collars: These collars apply pressure to the throat so the horse can't arch his neck and suck in air. Keep in mind that they may cause lesions on the horse's neck.
6. Shock collars: Seen as cruel by many, they shock the horse when the neck is flexed.
7. Cribbing muzzles: These allow the horse to eat and drink, but don't allow the mouth to stretch around a solid object.
8. Cribbing Rings:  These rings fit around the horse's teeth, but don't stay in place long and will slow down grazing.
9. Surgery: A modified Forssell's procedure is performed by cutting the muscles and nerves in the horse's neck and removing muscle tissue, making it difficult for the horse to arch his neck and suck in air.
10. Unpalatable paint: Painting premises with pepper sauce or other obnoxious coatings works with some horses, but certainly not all.

Catching cribbing behavior early in the game is extremely important. By being observant and making sure your horse gets plenty of exercise, has companionship and sufficient foraging opportunities, and by taking steps to curtail cribbing behaviors when they do appear, you should be able to keep your horse from engaging in this destructive activity.