White line disease (also known as seedy toe) is a fungal infection of the horse's hoof.
[2] White line disease may not be noticed by the horse owner and is most often diagnosed by a farrier during routine hoof trims or shoeing.
[citation needed] White line disease is most often seen in moist, humid areas with large annual rainfall totals.
[citation needed] Hoof infections are often attributed to poor management, but with white line disease this is often not the case, as it is seen even in horses kept in very clean stables and facilities.
White line disease is sometimes treated by applying borax or bleach solution to the affected area of the hoof, but this is not often successful.