What causes BOAS?
BOAS is caused by deformities in the dog's internal structure due to the shape of his skull and nose. These deformities include nostrils that are too narrow to breathe through properly, obstructed or collapsed voice boxes, elongated soft palates and abnormally small windpipes. Not each of these will occur in every breed or every dog, but finding at least one is common.
While some symptoms of BOAS - like snoring or noisy breathing - are mild, there are larger problems, too. Dogs with BOAS can also experience difficulty eating, rapid breathing or panting, coughing, gagging and difficulties with physical activities. Particularly, these breeds easily overheat in warm temperatures because their condition doesn't allow them to cool themselves off as effectively as they should be able to.