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Dicrocoelium dendriticum (view source)
Revision as of 14:26, 22 December 2008
, 14:26, 22 December 2008New page: == ''Dicrocoelium dendriticum'' == *This is a small fluke (less than 1.5cm) found in the bile ducts of ruminants and some other herbivores. *The flukes migrate directly up the common bile...
== ''Dicrocoelium dendriticum'' ==
*This is a small fluke (less than 1.5cm) found in the bile ducts of ruminants and some other herbivores.
*The flukes migrate directly up the common bile duct to reach the bile ducts within the liver - they are therefore much less pathogenic than ''Fasciola'' (which burrow through the liver parenchyma).
*''Dicrocoelium'' is rare in Britain, occurring mainly in the Hebrides, but is common in Europe.
*Small dark-brown eggs are shed in faeces.
*These contain a miracidium.
*If ingested by a land snail, the flukes develop, forming cercariae.
*These are excreted by the snails in slime-balls, which are collected and eaten by wood-ants.
*Metacercariae form inside the ants.
*The final host is infected when ants are eaten with grass.
*The presence of metacercariae in the nerve ganglia of the ants makes them revert to a primitive behaviour pattern, whereby they cling onto herbage overnight instead of retreating to the nest.
*This enhances the likelihood of being eaten by grazing animals.