Many Events Increase Equine Stress

Cortisol has been identified as a hormone indicating stress level in horses. When cortisol was measured in equine saliva before and after various events, researchers found that stress increased during presentation for sale, various types of schooling, and at competitions (show jumping and dressage). Cortisol levels dropped quickly after all events and were back to normal within an hour for some events.
Following the competitions, cortisol was still somewhat elevated after two hours. The highest levels were found in young horses being introduced to mounted work; horses being transported; and horses undergoing castration or colic surgery. Older horses showed less stress than younger horses in situations like horse shows, probably because of familiarity with the events. Horses also seemed to anticipate stressful events, as cortisol levels rose while horses were being prepared for events such as riding and showing.