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Horse Stereotypies Vary by Discipline, Researchers Say
by: Christa Lesté-Lasserre
March 04 2010, Article # 15919

Some horses crib, some weave, some chew wood. Some have many in-stall habits, while others have practically none. But these equine stereotypies are not as random as they might seem. According to recent findings from an equine behavior research group in northwestern France, they point to the kind of work those horses are doing outside their stalls.

Because of the different kinds of stress horses experience in different disciplines, their "bad habits," or stereotypies, will also vary, said Martine Hausberger, PhD, director of the Laboratory of Animal and Human Ethology, a branch of the French national research center (CNRS) and of the University of Rennes 1. Her group studied 77 French saddle horses at the Ecole Nationale d'Equitation at Saumur over a one-month period to observe their in-stall behavior. All of the horses included in the study worked one hour per day and spent the other 23 stalled.

In their study, the most serious kinds of stereotypies--cribbing, wind-sucking, and head shaking--occurred with dressage mounts and horses of the haute école (classical dressage, including airs above ground). Some of these horses performed a combination of stereotypies, and they performed them more frequently than the other horses. "These horses are under immense pressure to control their movements and restrict their emotions," Hausberger said.

Jumping and eventing horses had a greater tendency to lick or bite their surroundings, which are minor stereotypies, the authors reported. "They're under pressure when working," said Hausberger, "but they have more freedom of movement and expression during their workouts." They might also be seeking more nutrients from their environment due to the amount of energy they expend, she added.

Vaulting horses, which pass their working time longed while supporting the acrobatic movements of humans on their backs, generally only showed tongue play habits. These stereotypies were considered the least serious of all, Hausberger said, and were likely a reaction to being tightly reined in during their longeing sessions.

"These results strongly suggest that work stressors are one of the sources of stereotypic behaviors," Hausberger said. "Unfavorable housing conditions--the tight confinement of stalls, separation from other horses--probably make the problems worse."