Sweat and salts left on the skin can cause irritation and inflammation. Always use a thick sponge soaked in warm water and an anti-fungal/anti-bacterial shampoo designed for horses to get into all those hard-to-reach areas. After washing, make sure you dry thoroughly and don’t allow water to run down his legs or belly. You might also like to try a cortisone ointment which is a steroidal treatment that often decreases inflammation. However, never use a cortisone on an open wound as this may slow healing.