Dust causes coughing?

Most often, tiny dust particles, which are airborne or reside in the horse feed cause a horse to cough. The debris particles settle in the lung, resulting in infected alveoli being evident as the horse shows a runny nose, coughs or breathes heavily. We recommend watering the ground in the arena regularly, as well as the hay – and sweep the barn aisle after wetting it first, when horses are in their stalls. If hay as well as straw is cut too low to the ground, more dirt is trapped – high quality hay contains distinctly less dust. Ideally a horse is kept in an open door stable with plenty of fresh air around.