Changes

[[Image:Dicrocoelium dendriticum.jpg|thumb|right|150px|''Dicrocoelium dendriticum'' - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]

[[Image:Dicrocoelium dendriticum.jpg|thumb|right|150px|''Dicrocoelium dendriticum'' - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]

[[Image:Dicrocoelium dendriticum adult.jpg|thumb|right|150px|''Dicrocoelium dendriticum'' adult from horse faeces - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]

[[Image:Dicrocoelium dendriticum adult.jpg|thumb|right|150px|''Dicrocoelium dendriticum'' adult from horse faeces - Joaquim Castellà Veterinary Parasitology Universitat Autònoma de Barcelona]]

*This is a small fluke (less than 1.5cm) found in the bile ducts of ruminants and some other herbivores.

*This is a small fluke (<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).

*The flukes migrate directly up the common bile duct to reach the bile ducts within the liver

*''Dicrocoelium'' is rare in Britain, occurring mainly in the Hebrides, but is common in Europe.

**They are therefore much less pathogenic than ''Fasciola'' (which burrow through the liver parenchyma)

*Small dark-brown eggs are shed in faeces.

*''Dicrocoelium'' is rare in Britain, occurring mainly in the Hebrides, but is common in Europe

*These contain a miracidium.

**Small dark-brown eggs are shed in faeces

*If ingested by a land snail, the flukes develop, forming cercariae.

**These contain a miracidium

*These are excreted by the snails in slime-balls, which are collected and eaten by wood-ants.

**If ingested by a land snail, the flukes develop, forming cercariae

*Metacercariae form inside the ants.

**These are excreted by the snails in slime-balls, which are collected and eaten by wood-ants

*The final host is infected when ants are eaten with grass.

**Metacercariae form inside the ants

*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.

**The final host is infected when ants are eaten at grazing

*This enhances the likelihood of being eaten by grazing animals.

**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