Lower Respiratory

The lower respiratory system is comprised of the trachea, bronchi, and lungs. The lungs of the rat, like in humans, lie on each side of the heart in the chest cavity, but rat lungs differ from humans in the division of lobes. The left lung of the rat contains one lobe while the right contains 4 lobes. In humans the right lung contains three lobes while the left contains two.

While there may be some structural differences and variation of nerve innervation of the lungs between humans and rats, for the most part, respiration remains the same.

In newborn rats the lungs are not yet mature. The alveoli and alveolar ducts do not develop until the 7th day following birth. Up to that point the gas exchange of breathing occurs by way of smooth-walled channels and saccules. By day 13 the restructuring of lung parenchyma is complete.

Respiratory disease is among the most common health issue in rats. Learning to recognize your rat’s normal healthy behavior can alert you to early signs of illness. In addition, seeking treatment at the earliest signs of illness (e.g., upper respiratory issues or porphyrin staining) can often increase life span and comfort for your rat.