Obsessive compulsive disorders in horses

Hey there, time traveller!
This article was published 03/10/2016 (3504 days ago), so information in it may no longer be current.

Horses, like people, can develop obsessive behaviours which can dramatically affect their quality of life.

The most common compulsions, otherwise known as stereotypies, include cribbing, weaving, stall walking, pawing, head bobbing or compulsive head movements, biting/oral fixation, wall kicking or aggressive lunging.

Some of these behaviours are associated with boredom and some with pain avoidance.
Obsessive yawning or tongue movements can be associated with gastric or hind gut ulcers or other abdominal pain. Most stereotypic behaviours are functionless, repetitive actions a horse makes without any known cause. Genetics is thought to play a role in their development but environment around can also play a significant role.

Horses that crib (also known as wind-sucking, wood-biting or breath-holding) repeatedly place their upper incisors over a solid object, then bite or pull down while contracting the muscles in the neck responsible for flexing the head and/or swallowing. It was once thought such horses were intentionally swallowing air, but research has shown they suck air into the esophagus and then expel it again. Occasionally though, some air will get trapped and sucked into the stomach which can result in various types of colic; the worst-case scenario being an epiploic foramen entrapment of the small intestine which can be deadly.

Various methods are used to attempt to correct this behaviour including medication, alternative medicine modalities, aversion devices and surgical augmentation. However, a definitive therapy has yet to be devised.

Weaving and stall-walking/circling are also common compulsions. These horses will obsessively weave back and forth in front of a stall door or circle around their stalls repeatedly. Some methods used to control this behaviour involve modifying the way these horses are fed to provide them with more time to eat (slow feeding hay bags), various pheromones, medications, placement of mirrors in front of the stall, play balls in the stall and cross-tying the horse. Again, a definitive therapy has yet to be devised.

If you have a horse that has developed one of these stereotypies and would like further information, contact your equine veterinarian.

Chris Bell is an equine veterinarian and surgical specialist who operates Elders Equine Veterinary Service, with clinics in Cartier and Winnipeg. See www.eldersequineclinic.com.