Sub-clinical diseases affecting performance in Standardbred trotters: diagnostic methods and predictive parameters

Area of Science:

• Equine Sports Medicine
• Veterinary Internal Medicine

Background:

• Poor performance in Standardbred horses is a significant concern in equine sports.
• Identifying underlying sub-clinical diseases is crucial for effective management and performance enhancement.

Purpose of the Study:

• To determine the prevalence of sub-clinical diseases in poorly-performing Standardbred horses.
• To compare the physiological response to exercise between poorly-performing and control horses.
• To identify predictive parameters for poor performance.

Main Methods:

• Fifty horses underwent comprehensive clinical and ancillary examinations.
• Evaluations included haematology, biochemistry, Doppler echocardiography, standardized exercise tests (SETs), treadmill video-endoscopy, and respiratory fluid analysis.
• Physiological responses, including blood lactate (LA) and heart rate (HR), were measured during SETs.

Main Results:

• Most poorly-performing horses had multiple concomitant diseases, primarily affecting the respiratory and musculoskeletal systems.
• Poor-performers exhibited lower speeds at specific blood lactate (V(LA4)) and heart rate (V(200)) thresholds.
• Lower haematological parameters, plasma angiotensin-converting enzyme, and antioxidant levels were observed in poor-performers compared to controls.

Conclusions:

• Sub-clinical respiratory and musculoskeletal diseases are frequently diagnosed in poorly-performing Standardbreds.
• Standardized exercise tests and specific blood markers can serve as non-specific diagnostic tools for early disease detection.
• Early identification of these conditions can aid in improving equine athletic performance.