Cribbing and Wood Chewing
By: Dr. Lydia GraySmartPak strongly encourages you to consult your veterinarian regarding specific questions about your horse's health. This information is not intended to diagnose or treat any disease, and is purely educational.
Brief Description
Cribbing is one of several “stereotypies” or seemingly functionless, repetitive behaviors that also include weaving, stall-walking, pawing and head bobbing. Wood chewing, although related to cribbing and much more common, appears to be a normal behavior in horses that may be seeking more long-stem forage or “chew time.”
Cribbing is different from wood chewing. Cribbing specifically refers to when a horse grasps an object with its front teeth, pulls back, arches its neck, and appears to draw air into its esophagus, while making a characteristic grunt. Research has shown a link between cribbing and a specific kind of colic called “epiploic foramen entrapment.” Other reasons to discourage cribbing are that it can lead to poor performance, weight loss and abnormal tooth wear, as well as be hard on property.
Supplements that May Lend Support
Though the cause or causes of cribbing have yet to be identified, one theory suggests cribbing may be associated with too much acid in the stomach or hindgut. If so, products that neutralize acid or maintain normal gastro-intestinal pH may be helpful. Since grain meals - which can lead to excess acid in the stomach or hindgut - have also been linked with cribbing, a diet based on forage and supplemented with a multi-vitamin/mineral instead of grain may be more appropriate for a cribber. Horses that chew wood also seem to benefit from more forage, multi-vitamin/mineral supplements, and supplements designed specifically for cribbers, such as Quitt.
Possible Diagnostic Tests
It is important to try and find out why a horse cribs and treat that specific problem or remove that cause of stress, if possible. A veterinarian can determine if excess acid in the stomach or hindgut is a factor leading to cribbing, and recommend treatment. How and where a horse is kept, as well as how and what he is fed, should also be closely examined for clues to why a horse cribs. For example, a horse kept in a stall and fed hay and grain twice a day may be more likely to crib than a horse maintained on pasture with several other horses.
Prescription Medications Available
There are no specific medications to treat cribbing. However, a recent study testing the ability of dextromethorphan to reduce the vice was very successful. Virginiamycin, an antiobiotic, is able to reduce acid in the hindgut, a potential cause of cribbing, but it has not been show to reduce actual cribbing.
Other Management Suggestions
Because of the link between the buildup of acid in the stomach and cribbing, experts recommend lots of pasture time with companions as one method to reduce cribbing. If a horse must be stalled, then a special cribbing “bar” can be constructed to allow the horse to relieve his stress without causing damage to himself or the barn. Stall toys may also be helpful. If necessary, some cribbing collars are able to reduce a horse’s ability to crib.
Questions to Ask Your Veterinarian
- Is cribbing a learned behavior that other horses will copy??
- Will my mare pass this vice onto her foals?
- Should I try GastroGard® if my cribber is found to have ulcers?
Additional Resources
Further Reading for You
From our Ask the Vet Blog:
Managing a Cribber
From The Horse Journal:
- Tell “Em To Quitt!, January 2005
- Miracle Collar Fights Cribbing Best, January 2004
- Santa Brings Toys for Horses, December 2000
Further Reading for Your Veterinarian
Archer DC, Freeman DE, Doyle AJ, et al. Association between cribbing and entrapment of the small intestine in the epiploic foramen in horses: 68 cases (1991-2002). J Am Vet Med Assoc. 2004 Feb 15;224(4):562-564.
Mills DS, Taylor KD, Cooper JJ. Weaving, Headshaking, Cribbing, and Other Stereotypies, in Proceedings. 51st Annu Conv Am Assoc Equine Pract 2005:221-230.
Rendon RA, Shuster L, Dodman NH. The effect of the NMDA receptor blocker, dextromethorphan, on cribbing in horses. Pharmcol Biochem Behav. 2001 Jan;68(1):49-51.
