Effect of temperament on cortisol response to a single exercise bout in Thoroughbred racehorses – short communication.

This research article investigates how the temperament of Thoroughbred racehorses affects their cortisol levels in response to exercise. It concludes that horses with a more excitable temperament showed a higher cortisol response, suggesting that temperament can influence a horse’s physiological response to exercise.

Research Context

• The authors address a gap in previous research, which did not consider temperament when studying the stress responses of horses to exercise. The authors argue that a horse’s personality could potentially play a role in how the animal reacts to physical activity.

Objective and Methodology

• The study aimed to investigate how a horse’s temperament might affect their cortisol response to a single exercise bout. Cortisol is a hormone that rises in response to stress, so examining cortisol responses can offer insights into how stressful a horse finds exercise.
• Twenty healthy Thoroughbred racehorses were selected for the study. Their temperaments were characterized using a 25-item rating questionnaire survey. This survey divided the horses into “temperamental” and “calm” groups, with eight falling into the first category and twelve in the second.
• The horses’ exercise routine consisted of a warm-up trot followed by a gallop on a rounded sand track. Blood samples were collected four times from each horse for cortisol analysis.

Findings

• The results showed that horses with more excitable temperaments produced a higher cortisol response to exercise compared to their calmer counterparts. This demonstrates that a horse’s basic personality can have a physiological effect, in this case influencing the stress response to physical activity (P = 0.036).

Conclusion

• The study concluded that temperament does affect cortisol levels in response to mild intensive exercise in horses. Essentially, more temperamental horses find exercise more stressful, according to their cortisol responses.
• The research also suggests that serum cortisol levels might serve as a potential marker to quantify individual temperamental differences in racehorses, providing a possible tool for trainers and veterinarians to better understand and manage the needs of individual horses.