Fecal Cortisol Metabolites Indicate Increased Stress Levels in Horses During Breaking-In: A Pilot Study

Area of Science:

• Equine Science
• Animal Welfare
• Sports Science

Background:

• Sport horses face numerous stressors impacting welfare, with cortisol release as a key indicator.
• Limited research exists on stress levels in young horses during the critical breaking-in phase of their sports careers.

Purpose of the Study:

• To compare stress levels, measured by fecal cortisol metabolite (FCM) concentrations, in unridden young horses versus those undergoing breaking-in and training.
• To investigate the impact of early training stages on stress indicators in young sport horses.

Main Methods:

• Fecal samples were collected from young unridden horses (n=28) and horses in different training stages (n=13).
• Fecal cortisol metabolite (FCM) concentrations were measured to assess stress levels.

Main Results:

• Unridden horses exhibited significantly lower FCM concentrations than horses in training (p < 0.001).
• Horses in their first year of saddle work showed significantly higher FCM levels compared to unridden horses (p < 0.05).
• A trend suggested decreasing FCM levels with increased time in training, alongside greater individual variability in ridden horses.

Conclusions:

• The breaking-in period represents a significant stressor for young horses.
• Implementing careful and considerate initial training practices is essential for mitigating stress in young sport horses.
• Individual differences in coping mechanisms for training-induced stress were observed in ridden horses.