Fibroscopic evaluation of the upper airways in thoroughbreds, post Competition at the La Plata racetrack, Buenos Aires, Argentina. Between 2019 – 2022.

Introduction: The horse is an obligate nasal breather, so upper airway obstructions (UAO) cause poor performance. Pharynx and larynx affections are the most frequent and present with clinical signs such as choking, respiratory noises and poor performance.

Objective: to evaluate the prevalence of static UAO in Thoroughbred horses that competed and requested a post-competition endoscopy at the La Plata racetrack.

Materials and methods: The post-race endoscopic examination was performed at the racetrack in the city of La Plata, Argentina, to all those horses that requested the study. A total of 898 Thoroughbred horses were endoscopically evaluated immediately after the end of the competition using an Olympus GIF fiberscope.

Results: Out of the total number of equines evaluated, 792 did not show alterations, 106 presented one or more alterations, of which 100 had only one condition and 6 more than one. The UAO observed were Dorsal Displacement of the Soft Palate (DDSP) (n=74), Epiglottic Entrapment (EE) (n=19), Recurrent Laryngeal Neuropathy (RLN) (n=12) and others (n=4). The presentation between females and males was 53 animals per category. Regarding the age of the horses, 2 years (n=11), 3 years (n=22), 4 years (n=36) and 5 years and older (n=37).

Discussion/Conclusion: We can conclude that 11.8% of the horses that requested endoscopies presented alterations in the upper airways, of which 94.3% presented a single UAO condition and 5.6% more than one. The prevalence of the disorders in the upper airways was 69.8% DDSP, 17.9% EE, 11.3% RLN, and the others were of very low incidence. In this study, there was no difference between sexes. And it was determined that the affections of the upper airways occurred to a greater extent when the age was higher.

References

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