[4] The species is yellow-white in color, with adults having a long body and a broad anterior end that has three shamrock-like lips.
[6] A protein layer surrounding most of the eggs enables them to stick to vertical surfaces and even to the hair and udder or a mare.
Adult P. univalens may live in the small intestine for many months and lay eggs anywhere from 90 –110 days after the initial infection.
Some signs and symptoms that the foals are infected with P. univalens include a lack of energy, coughing and nasal discharge.
[2] Some cases include impaired growth of foals and worm impaction can cause the small intestine to rupture.
[7] Standard treatment for Parascarsis involves using drugs that induce paralysis in the worms, this makes them detach from the intestines and allow the horse to pass them.
[2] A recent study on ascarids in Europe has discovered that P. univalens have started becoming resistant to a standard antihelmintic medication, pyrantel, whereas fenbendazole is still proven to be effective at removing the worms.