Clinostomum spp

From Cow
Clinostomum adult under light microscopy

Clinostomum spp are an intestinal parasitic trematode (fluke) of cattle in tropical regions of North and South America.

These flukes normally parasitize otters, fish and birds and cattle are considered an accidental host.

Species which are pathogenic in cattle include:

  • Clinostomum tilapiae[1]
  • Clinostomum heluans

Infective metacercariae are eaten by cattle during grazing. The adult fluke usually resides in the intestine and cause mild or asymptomatic disease. Once mature, the flukes pass eggs into the feces, which are passed out and contaminate pasture.

Clinical signs are often vague in cattle. Haematological changes are often nonspecific, including eosinophilia and decreased protein levels.

Diagnosis is based on presenting clinical signs, isolation of the parasite eggs in feces, identification of adult flukes in the intestines and laboratory analysis of parasite for identification.

Control of this parasite is through use of molluscicides to control the snail (intermediate host) as well as flukicidal drugs such as triclabendazole, closantel, moxidectin plus triclabendazole and oxyclozanide[2].


  1. Asanji MF & Williams MO (1975) Studies on the excystment of trematode metacercariae in vitro. Z Parasitenkd 47(2):151-163
  2. Merck Vet Manual