Haemonchus contortus, also known as the barber's pole worm, is very common parasite and one of the most pathogenic nematodes of ruminants. Adult worms attach to abomasal mucosa and feed on the blood. This parasite is responsible for anemia, oedema, and death of infected sheep and goats. The small purple blotches or petechiae are visible where the worms have been feeding.Photographed at the Moredun Institute.