Pharyngeal dysfunction during exercise

Summary Pharyngeal dysfunction in the horse during exercise has been poorly understood. Endoscopic examinations of these animals as they exercised on high-speed treadmills has allowed direct observation of many of these dysfunctions. There is still considerable variation in the interpretation of these findings. The existence and function of the oropharyngeal seal (OPS) is discussed as are several etiological bases for inappropriate pharyngeal function.