Heaves are a chronic respiratory condition caused by an allergic reaction to inhaled particles.

Proper feeding of horses with respiratory diseases is critical 

Most domestic horses eat hay.

Most hay contains mold and dust,which are respiratory irritants

Forage is an essential element of a horses diet.

Hay pellets and cubes are good alternatives to hay for horses with respiratory conditions.

You can still feed hay to horses with heaves, but it should first be soaked or steamed to reduce dust.