Prevalence of pharyngeal, laryngeal and tracheal disorders in thoroughbred racehorses, and effect on performance.
Authors: Saulez M N, Gummow B
Journal: The Veterinary record
Summary
# Editorial Summary Saulez and Gummow conducted post-race endoscopic examinations on 1,005 South African thoroughbreds within 24 minutes of racing to establish the prevalence of upper airway disorders and their relationship to competitive performance metrics. Whilst structural abnormalities such as laryngeal dysfunction, epiglottic entrapment and subepiglottic cysts were relatively uncommon (affecting fewer than 3% of horses), inflammatory and mucus-related findings dominated the sample: pharyngeal lymphoid hyperplasia occurred in 63% of horses, laryngeal debris in 43.5%, and virtually all horses (99.5%) exhibited tracheal mucus post-exercise. Importantly, horses with grade 2 and 3 pharyngeal lymphoid hyperplasia showed measurably reduced performance in terms of race wins and placed finishes, whilst notably, tracheal cartilaginous nodules—present in 6.8% of the population—were associated with *improved* performance outcomes, particularly in male racehorses. These findings challenge the assumption that all post-exercise upper airway findings are performance-limiting; they suggest that veterinary and coaching teams should prioritise investigation and management of pharyngeal lymphoid hyperplasia as a potential performance constraint, whilst reconsidering the clinical significance of incidental findings such as tracheal nodules that may reflect physiological adaptation rather than pathology.
Read the full abstract on PubMed
Practical Takeaways
- •Endoscopic findings of moderate pharyngeal lymphoid hyperplasia warrant attention as they correlate with reduced racing performance, particularly in younger horses
- •Common post-race findings like laryngeal and tracheal debris should not be assumed to impair performance; severe laryngeal dysfunction is rare and not performance-limiting in this population
- •Tracheal cartilaginous nodules, though more prevalent in males, do not indicate poor prognosis and may even be associated with competitive success
Key Findings
- •Grade 2-4 pharyngeal lymphoid hyperplasia had high prevalence (63%) and impaired performance in horses with grade 2-3 PLH
- •Low prevalence of severe laryngeal dysfunction (2.2% grade 2-3, 0.6% grade 4) with no measurable effect on performance
- •Tracheal cartilaginous nodules (6.8% prevalence) were more common in males and associated with better performance
- •Laryngeal debris (43.5%) and tracheal debris (21.9%) were common but did not affect racing performance