UPPER AIRWAY EVALUATIONS OF THOROUGHBRED RACEHORSES IN A PRIVATE CLINIC IN CURITIBA, BRAZIL – RESTING ENDOSCOPIC FINDINGS IN 587 HORSES

Abstract

Obstructive upper airway diseases are an important cause of poor performance in athletic horses. The present study aimed to determine the prevalence of common URT abnormalities (pharyngeal lymphoid hyperplasia - PLH, dorsal displacement of the soft palate - DDSP and recurrent laryngeal neuropathy - RLN) in a population of Thoroughbred racehorses in training submitted to resting endoscopy in a private clinic in Curitiba, Paraná, Brazil. 587 URT resting endoscopies, 385 2-year-old and 202 3-year-old-plus horses, were performed during the period of the study and the clinical records of all the examinations were reviewed and analysed. 340 (57.9 %) horses were evaluated for routine athletic follow up, 15 (2.6%) were pre-purchase examinations, 83 (14.1%) were examined as an investigation for cough, 58 (9.9%) horses had poor performance, 48 (8.2%) had abnormal respiratory noise, 35 (6.0%) had epistaxis and 8 (1.4%) had nasal discharge. Pharyngitis (Grades III, IV PLH) was diagnosed in 198 (33.7%) horses and was more prevalent in the 2-year-old group than in the older horses (40.5% vs. 20.8%, P<0.05). DDSP was identified in 185 (31.5%) horses, Grade III RLN in 13 (2.2%) and Grade IV was seen in 21 (3.6%) horses. The present study gives a prevalence of upper airway abnormalities in resting endoscopic evaluation in a racehorse population in Brazil.