Changes

==Description==

==Description==

Summer Pasture-Associated Recurrent Airway Obstruction (SPA-RAO) is an inflammatory condition of the lower airways affecting pasture-kept horses. This is in contrast to Recurrent Airway Obstruction that affects horses that are kept in a stabled environment. SPA-RAO is characterised by airway inflammation, increased airway mucus production, reduced mucociliary clearance and bronchoconstriction in response to allergen exposure. The pathogenesis of the disease is largely unknown but suggested hypotheses include inhaled pollens or outdoor moulds, or ingestion of a pasture-derived pneumotoxin. It occurs most commonly in the southern states of America but has also been reported in the United Kingdom.

Summer Pasture-Associated Recurrent Airway Obstruction (SPA-RAO) is an inflammatory condition of the lower airways affecting pasture-kept horses. This is in contrast to Recurrent Airway Obstruction that affects horses kept in a stabled environment. SPA-RAO is characterised by airway inflammation, increased airway mucus production, reduced mucociliary clearance and bronchoconstriction in response to allergen exposure. The pathogenesis of the disease is largely unknown but suggested hypotheses include inhaled pollens or outdoor moulds, or ingestion of a pasture-derived pneumotoxin. It occurs most commonly in the southern states of America but has also been reported in the United Kingdom.

==Signalment==

==Signalment==