Brachycephalic obstructive airway syndrome (BOAS) causes chronic breathing difficulty in flat-faced dog breeds, representing one of the most significant welfare problems caused by deliberate breeding selection.
BOAS is a welfare crisis created by human aesthetic preference for flat-faced dogs. Individual dogs with severe BOAS live in a state of chronic respiratory compromise - struggling for air during exercise, in heat, and even at rest. The normalisation of these signs ('that's just how this breed sounds') prevents many dogs from receiving the corrective surgery that would significantly improve their welfare. The most effective long-term solution is breeding away from extreme brachycephalic conformation; consumer choices that avoid the most severely affected breeds, and breed standards that penalise extreme features, drive this change.