Thysanosoma actinoides: Fringed tapeworm

General Description: Adults are up to 15 to 30cm long and 8mm wide with an unarmed scolex of 1.5 mm maximum width. Proglottides are 5 to 6 times wider than long and have a conspicuous fringe on their posterior surface.

Life Cycle: Unknown.

Location: Bile ducts, pancreatic ducts and small intestine.

Geographical Distribution: South America, southern and western United States.

Significance: Condemnation of livers at slaughter makes the fringed tapeworm an economic problem.

Effect on Host: Not well understood. Adults may block the flow of bile and pancreatic juice, thus distributing digestion and causing decreased gains in animals. Decreased weight gain may be the only sign of infection.

Diagnostic Information: Small, fringed proglottides containing thick-shelled circular eggs appear in faeces.

Control: Anthelmintic treatment of sheep to rid them of adults is the only method at present.

Adult tapeworms displaying fringe surface		Thysanoma – fringe of proglottids