Lower airway disease

What are symptoms

Symptoms are the signs, or abnormalities observed by the pet or owner, in a diseased person or animal.   A sign of lower airway disease may include extra sounds heard through the stephoscope when a dog breathes.  Symptoms may include coughing or turning blue or finding it difficult to exercise, shallow breathing or laboured breathing.  Some dogs with lower airway disease show no signs at all that the owner has noticed.  I can't help but think that we're coming at this question from an unusual angle - usually we'd start with a dog showing some signs and then pinpoint a place in the body (such as the lower airways) to investigate further and then try to work out what specific disease or process we're looking at.  Is there a story behind this question?