Cribbing in Horses
Once known as a stable vice, cribbing is now considered by equine behaviorists as a stereotypical oral behavior. Cribbing behavior (sometimes referred to as crib-biting) is rarely, if ever, seen in free-living feral horses but is frequently found in domesticated horses, leading researchers to believe that such unwanted behavior is caused by the way we manage our horses. When a horse cribs he grabs onto a solid object with his teeth, arches his neck, pulls against the object, and sucks in air. Windsucking is similar to cribbing but the horse does not need to hang onto an object in order to suck in air.
What we don’t know about cribbing
Equine behaviorists are unsure why horses crib. One theory suggests that endorphins released in the brain during cribbing behavior result in a “horsey high” but research trials studying this theory have returned contradictory results. Another theory compares cribbing to obsessive compulsive behavior in humans, citing the possibility of a true neurological pathology. There is some evidence that genetic predisposition may also play a role, especially in Thoroughbreds.
What we do know about cribbing
Cribbing tends to begin around weaning time. Foals weaned onto a high-grain diet are more likely to begin cribbing than those that are weaned on pasture. Foals weaned in groups are less likely to exhibit cribbing behavior. Foals that crib have a higher incidence of gastric ulcers, but researchers are caught in the old “which came first” quandary, the ulcer or the cribbing? Several research trials have shown that foals supplemented with gastric acid neutralizers exhibit a reduced incidence of cribbing.
Contrary to popular belief, cribbing is not a learned behavior passed from horse to horse. When clusters of cribbers are found, behaviorists often see underlying management routines that contribute to the development of the behavior. Social isolation, exposure to aggressive horses, and other stressful events have been found to aggravate cribbing.
Chronic cribbing leads to other problems, such as excessive wear of the incisors that impact a horse’s ability to eat properly and an increased incidence of colic. Cribbers are often blamed for damaging fences, stalls and barns as they repeatedly grasp and pull on solid objects in front of them.
Managing the cribber
When cribbing behavior is noted, the best way to curtail it is to determine the underlying problem causing the behavior and remove it if possible. This is particularly important in young horses. In the older confirmed cribber, this can be more difficult. Reducing stress, and encouraging and providing opportunity for social interactions have been found to reduce cribbing. Feeding a high-fiber, low-grain diet and providing as much turnout on pasture as possible are also helpful. The use of cribbing collars to dissuade a horse from engaging in the behavior can be helpful; however, in some horses it only causes increased stress and frustration.