Otitis externa in eight horses - clinical signs, treatment and prognosis.

Abstract

BACKGROUND: Otitis externa is rare in horses and the condition is poorly described in the literature. OBJECTIVE: To describe clinical signs, treatment regimens and prognosis of otitis externa in horses. ANIMALS: Eight horses diagnosed with otitis externa during 2011-2018. METHODS: Retrospective review of medical records and follow-up contact with owners. RESULTS: Common clinical signs seen in affected horses were pruritus, ear discharge and ear droop of affected ears. The most common cytological findings were neutrophils, bacteria and yeast. All horses responded well to treatment; two horses were reported to have recurrent problems. CONCLUSION AND CLINICAL IMPORTANCE: Otitis externa in horses is a rare and treatable condition. The condition may be present for prolonged periods before owners become aware, compromising the welfare of affected horses. Untreated otitis externa is a suggested cause of otitis media and temporohyoid osteoarthropathy, emphasizing the importance of identifying and treating this condition at an early stage. For this reason, clinicians should include a brief inspection of the pinnae and external ear canal in the clinical examination of horses.