Equine lung inflammation in Alberta: evaluation of clinical signs, risk-screen questionnaire, and bronchoalveolar lavage in recurrent airway obstruction and inflammatory airway disease

Abstract

Non-infectious equine respiratory diseases consist of recurrent airway obstruction (RAO) and inflammatory airway disease (IAD). Recurrent airway obstruction has similarities with human asthma, whereas horses with IAD have a milder airway inflammation and do not exhibit respiratory clinical signs at rest. This thesis presents a review on RAO and IAD, followed by a manuscript on the evaluation of a risk-screening questionnaire (RSQ) to detect equine lung inflammation measured by a bronchoalveolar lavage (BAL) in a large field study. The RSQ had a high sensitivity to detect severe lower airway inflammation and would be a good screening tool in practice. Furthermore, there was a high prevalence of moderate airway inflammation in this population, but the RSQ did not differentiate between moderate airway inflammation and normal horses. Finally feeding round hay bales was a risk factor for severe airway inflammation.