A genus of small, slender nematodes (family Trichostrongylidae) inhabiting the small intestine, rarely the abomasum, of ruminants; when fresh they are a bright pink color; they produce serious effects only when present in large numbers. In partly immune animals, these worms become enclosed in nodules in the wall of the intestine; they are less pathogenic in sheep and goats than the trichostrongyles Haemonchus, Ostertagia, and Trichostrongylus. Abbreviated taxonomy: Nematoda, Chromadorea, Rhabditida, Strongylida, Trichostrongyloidea, Cooperiidae
a genus of intestinal nematodes in the family Trichostrongylidae. Principal infestations in sheep and goats, C. punctata, C. oncophora, C. curticei; in cattle, C. oncophora, C. pectinata, C. punctata; miscellaneous infections with other species in ruminants generally are C. bisonis, C. spatulata, C. surnabada (syn. C. mcmasteri). The worms inhabit the small intestine. See also cooperiasis.