Both an acute and chronic form of larval cyathostomosis occur in horses. The acute form occurs due to the re-emergence of 'encysted' (hypobiotic) thrid stage larvae from the intestinal wall, and horses with this type of disease are usually affected during late winter or early spring. | Both an acute and chronic form of larval cyathostomosis occur in horses. The acute form occurs due to the re-emergence of 'encysted' (hypobiotic) thrid stage larvae from the intestinal wall, and horses with this type of disease are usually affected during late winter or early spring. |