The equine respiratory system is geared for athleticism.
Principal Body System: Respiratory
Definition: The lungs and a series of associated passageways leading into and out of them.
Function: Supplies oxygen; elimintaes carbon dioxide, helps regulate the acid-base balance of the body.
With a huge lung capacity to enable air-intakes of up to 1800-litres/minute in a galloping horse, up to 300-litres of blood are pumped at high pressure at full gallop through tiny lung capillaries surrounding 10-million air-sacs, to take up and deliver over 70-litres of oxygen, per minute, to the working muscles. Phew!
As a result, any related condition that reduces efficiency of oxygen uptake from the air sacs can have a significant influence on athletic capacity. As fate would have it, in domesticity, the equine respiratory system is continually being challenged by our world, everything from stables to school surfaces, dusty bedding to feed.