what causes a horse to have a runny nose
Runny Nose: Should You Call the Vet?By Kentucky Equine Research Staff Â· March 10, 2011. A little bit of clear nasal discharge is not uncommon after healthy horses exercise or play energetically. Owners might also see this type of discharge if a horse has been eating hay, and most of the time this runny nose is simply a harmless result of slight irritation from fast breathing or exposure to low levels of dust.