During that time, they inflame the artery walls and create blood clots which interfere with the flow of oxygen and nutrients to the intestines. Often referred to as cyathostomes, these parasites are perhaps the most significant cause of chronic under-performance, loss of condition, feed inefficiency and predisposition to secondary diseases. Small strongyles are extremely prolific. A single horse may harbor hundreds of thousands of worms at any given time. When small strongyle larvae emerge from the lining of the intestines, usually in large numbers, they leave behind an ulcerated gut wall.
Adult roundworms are relatively large and visible to the naked eye.
Far more dangerous to the horse, however, is the migration of roundworm larvae through the lungs and liver. Through the years Herds of wild horses have roamed the grasslands of earth for more than 70 million years, but only for the past 4,000 years have horses lived in close association with people. Instead of roaming over vast areas, most horses today are kept in small stalls and paddocks, close to other horses. A constant threat In its clinical manifestation, internal parasite damage takes the form of fever, loss of appetite, colic, even death. Your horses are exposed to the threat of parasites every day.