Atlas of livestock parasites
digitized collection of microscopical preparations

Atlas of Parasites Contents Information sources Glossary Administration

Cysticercus ovis



Untitled document

Cysticercus ovis
(adult tapeworm is Taenia ovis)
Sheep tapeworm of dogs, sheep measles.

General Description:
The principal host of this parasite is dog. Sheep serve as the intermediate host. In sheep the parasite appears as small, fluid-filled cysts which give spotty or measles-like appearance to the sheep muscle.

Life Cycle:

Proglottids of the tapeworm leave dog in the feces and are eaten by sheep. The eggs in the proglottids hatch in the intestine. Immature forms penetrate the gut wall and are carried in the blood to muscles where they become a cysticercus which is a bladder worm with a scolex inside. Dogs are infected by eating raw measly sheep muscles containing viable cysticerci. Adults develop in man in 3 weeks or more.

Adults in small intestine of dogs. Cysticerci in striated muscles of sheep, anywhere in the body.

Geographical Distribution:

Inspection of sheep carcasses for Cysticercus ovis in order to avoid human consumption is time-consuming and expensive. Carcasses containing sheep measles are condemned. Dogs infected with Taenia tapeworms may be unaffected or have loss of appetite and diarrhea. Sheep are usually unaffected by Cysticercus ovis.

Effect on Host:

Full-grown bladder worms are 6 mm by 5.5 mm and are not harmful to sheep.

Diagnostic Information:
Infected dogs may show proglottids in feces.

Dogs with Taenia ovis shed eggs in feces. Sheep exposed to the tapeworm eggs may become infected. Water used for livestock purposes, either for drinking or pasture irrigation, should be free of fecal contamination. Dogs should receive periodic anthelmintic treatments with products effective against tapeworms.


No picture to show.

<<< Back