lungs

Common Respiratory Problems

Respiration is the process by which gas exchange between the atmosphere and the lung tissue occurs, it is driven by the mechanical process of breathing created by movement of the rib cage and diaphragm. Within the lungs the oxygen is picked up by the blood and carbon dioxide discharged into the air. The blood is circulated to the lungs by the right side of the heart, it is returned to the left side of the heart and thence pumped around the body.

The airways start with the trachea (windpipe) which runs from the larynx to the chest, in the chest it divides into two bronchi which branch off into each lung. In the dog the left lung has 2 lobes and the right lung is split into 4 lobes.

The lungs and chest cavity are lined by membranes known as the pleura. The space between these membranes is referred to as the pleural cavity.

Disorders of the respiratory system can be due to infectious causes, inflammatory or immune related disorders, cancer, or structural abnormalities. Respiratory problems can also be manifestations of disease in other body systems, for example heart problems.

Distemper: a viral disease of dogs causing acute onset respiratory, intestinal and nervous problems. Now controlled by vaccination.
Kennel Cough: highly infectious disease caused by several bacterial and viral agents. Affected dogs develop a harsh, hacking cough and fever.
Filaroides: a lungworm that can develop in the respiratory tract of dogs. Presents with coughing spasms.
Actinomycotic Infections: can develop into a pleural effusion (chest fluid build up), leading to breathing difficulty.
Allergic pulmonary disease immune system malfunctions causing chronic or recurrent coughing.
Bronchial Foreign body: inhaled objects which become lodged in the lung passages.
Bronchiectasis: this often develops as a sequel to other problems. It is a chronic end stage distension of the lung passages which disrupts their function.
Chronic Bronchitis: can be caused by infection or inhaled irritants, causes chronic cough and bronchial wheezing.
Lung neoplasia: cancer can arise as a primary tumour within the lung tissue but it is also a frequent site for spread from tumours elsewhere.
Pneumonia: inflammation of the lung, often due to bacterial or viral infection, causes an increased rate and depth of breathing and coughing. Other signs of illness such as fever or even collapse can be present if problem is severe.
Tracheal collapse: this is a structural disorder of the windpipe that causes it to fold in on itself during inspiration. Often occurs in miniature or toy breeds causing a honking cough.