Hypothalamic-pituitary-adrenal axis responses of horses to therapeutic riding program: effects of different riders.

This study explores how the stress levels of horses, as gauged by their hypothalamic-pituitary-adrenal (HPA) axis responses, vary when used in therapeutic riding versus recreational riding. The researchers determine that horses used in therapeutic riding display significantly lower levels of the stress hormone cortisol, and hence less HPA axis response, suggesting that they experience less stress with disabled riders compared to recreational riders.

Research Context and Method

• The research was conducted to understand if therapeutic horse riding, which is a common activity for individuals with psychomotor disabilities, caused higher levels of stress to horses than recreational riding.
• The study used six horses that had been accustomed to both therapeutic and recreational riding since 2004.
• The HPA axis responses were gauged by examining the concentrations of β-endorphin, ACTH, and cortisol in the horses. These substances are typically released in response to stress.
• Two types of 60-minute riding sessions were conducted – therapeutic sessions (session A) with six children with psychomotor disabilities, and recreational sessions (session B) with six healthy children with no prior riding experience.
• The horses performed the same exercises in each session to maintain consistency.

Findings

• Statistical analysis of the results collected over the six weeks showed that there was no significant change in the average basal levels of β-endorphin and ACTH during both sessions.
• However, the cortisol levels showed a significant difference. The one-way RM-ANOVA demonstrated that sessions with therapeutic riders (session A) impacted the horses’ cortisol levels.
• Horses showed lower cortisol levels at both 5 minutes and at 30 minutes after the therapeutic riding sessions in comparison to the recreational riding sessions.
• The finding suggests that the horses’ HPA axis was less responsive, and hence less stressed, when they were ridden by the children with disabilities than when ridden by the healthy, recreational riders.

Conclusion

• Among endocrine responses, cortisol was noted to be an indicator of an HPA axis stress response in horses.
• The research concludes that, based on the examined variables, therapeutic riding does not cause more stress to horses than recreational riding. In fact, horses seem to undergo less stress when involved in therapeutic sessions as compared to recreational sessions.