Any horse that is performing with its rider or driver, competitively or recreationally, is an athlete. The horse is naturally an elite athlete and in order to function as an athlete the horse needs to be sound, breathe efficiently and have a well functioning heart. Although it is relatively easy to diagnose a horse that is limping badly or coughing hard, identifying minor problems, which may cause your horse to be "off", can be a challenge.
The University of Minnesota Veterinary Hospital offers performance evaluation of the athletic horse. The use of a high speed treadmill allows us to observe the horse dynamically and is essential in diagnosing respiratory and musculoskeletal problems that arise only during extreme activity. Performance evaluations start with an in depth physical exam to make sure the horse is in shape to run on the treadmill. A thorough lameness work-up is performed to rule out the presence of a subtle lameness as an underlying cause of the poor performance. Then, the horse will undergo a resting heart examination including cardiac auscultation, an electrocardiogram (ECG) and an echocardiogram (ultrasound) to look for murmurs, dysrhythmias, heart contractility and heart valve problems.
The upper airway is also first examined at rest. An endoscopic exam allows evaluation of the nasal passages, the pharynx, larynx and trachea for any abnormalities in shape, position or movement. Some upper airway problems, such as severe left laryngeal paralysis (roarer) can be diagnosed at rest, others are better diagnosed during exercise. The horse is trained to run on the treadmill to become familiar with the sensation of the floor moving, most horses do adapt quickly. Once familiar with the treadmill, the horse is fitted with the videoendoscope camera and ECG. The upper airway is videotaped throughout the exercise to allow thorough evaluation of the airway dynamics and the horse is closely monitored for any signs of lameness, which might be evident only at higher speed. The combination of these tests give a good overview of the systems most important to the equine athlete and allows diagnosis of subtle poor performance problems, which would not be possible without observing the horse performing a controlled exercise test on the treadmill.