Overview of the feline airway and lungs — nasal passages, trachea, and alveolar lungs that carry out gas exchange in an obligate nasal breather.
General educational reference only — not clinical or veterinary advice. Anatomy varies between individual animals; consult a licensed veterinarian for any health concern.
Upper airway
Air enters through the nostrils and nasal cavity, which warm, humidify, and filter it before it reaches the lungs. Cats are predominantly nose breathers under normal conditions. Air then moves through the pharynx and the larynx, which also produces vocalizations and protects the airway during swallowing.
Lower airway and lungs
The trachea branches into bronchi and then into finer bronchioles that end in alveoli, the tiny sacs where oxygen and carbon dioxide are exchanged with the blood. The lungs are divided into lobes within the chest. The cat's airway is comparatively narrow.
Breathing mechanics
Breathing is driven by the diaphragm and the muscles between the ribs, which change the volume of the chest cavity. At rest, a cat's breathing is smooth and shallow. The purring vibration involves rapid movement of the laryngeal muscles.
Sources
Veterinary anatomy and physiology texts; Merck Veterinary Manual (general reference)
