No coughing or poor performance Poor performance cough Poor performance and cough Total
Number of horses 63 297 435 225 604
Age 9.4 (±4.2) 10.7 (±4.4) 10.8 (±4.7) 11.0 (±4.5) 10.5 (±4.5)
Normal BAL cytology 24 60 83 43 122
MEA 46 141 186 96 283
SEA 24 93 165 83 199