The common name for strongylus vulgaris is the large stronglydes. It’s commonly found in horses, and unfortunately for horses, this parasitic worm is often found in many horses year-round. This parasitic worm is basically a worm with a bite. They have large pincers on one end, with the other end acting as a butt.
If one were to be seen, it’d be a very deep red in color. This is because they drink a ton of blood from their host.
This particular strain of parasitic worm lives in one of two places: the horse’s intestines, or the grass it is about to eat. When the worm is an egg or early stage larva, it can live outside of a host.