Comparison of dynamic and resting endoscopy of the upper portion of the respiratory tract in 57 Thoroughbred yearlings.

Authors: Kelly P G, Reardon R J M, Johnston M S, Pollock P J

Journal: Equine veterinary journal

DOI: 10.1111/evj.12061 PubMed: 23521159Log in to save

Summary

# Editorial Summary Resting endoscopy has long been the standard screening tool for upper respiratory tract (URT) pathology in Thoroughbred yearlings, yet mounting evidence suggests it may miss dynamic airway abnormalities that only manifest during exercise. Kelly and colleagues compared resting endoscopic findings with dynamic endoscopy (performed during treadmill exercise) in 57 Thoroughbred yearlings to establish whether this additional diagnostic approach could improve detection of functional respiratory disease. The researchers found that dynamic endoscopy revealed significantly more pathology than resting examination alone, particularly for conditions such as dynamic laryngeal collapse and intermittent dorsal displacement of the soft palate—abnormalities that may only become apparent when the horse is working. Given that these functional defects can substantially impact racing performance and athletic soundness, incorporating dynamic endoscopy into pre-purchase and pre-racing evaluations could provide a more complete assessment of respiratory competence, especially in young stock where early identification of significant pathology might influence training decisions or management strategies. For veterinarians and those involved in yearling selection, this study underscores the limitations of relying solely on resting assessment and suggests that dynamic evaluation may be warranted when detailed respiratory clearance is required.

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Practical Takeaways

•Resting endoscopy alone is insufficient for pre-purchase or pre-racing evaluation of yearlings; dynamic endoscopy should be considered standard protocol
•Functional respiratory pathology may only manifest during exercise, making resting examination miss clinically significant conditions
•Incorporate exercise endoscopy into yearling vetting protocols to improve accuracy of fitness assessments for racing suitability

Key Findings

•Resting endoscopic examination of Thoroughbred yearlings is inaccurate for diagnosing functional upper respiratory tract pathology
•Dynamic endoscopy during exercise revealed pathology not detected on resting examination
•Comparison demonstrated superior sensitivity of dynamic versus resting endoscopy in 57 TB yearlings

Conditions Studied

upper respiratory tract functional pathologylaryngeal dysfunctiondynamic airway obstruction

Related References

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