Liver Flukes
Fasciola hepaticaIntroduction
Fasciola hepatica, also known as the common liver fluke or sheep liver fluke.Is a parasitic flatworm of the class Trematoda, phylum Platyhelminthes that infects liver of various mammals, including humans.
The disease caused by the fluke is called fascioliasis (also known as fasciolosis).
F. hepatica is world-wide distributed and causes great economic losses in sheep and cattle.
Fasciola hepatica
Fasciola hepatica lives in the liver of man.Intermediate host: Snail.
• Definitive host: Sheep & Humans (Accidental)
Infective stage (human): Metacercaria.
Diagnostic stage: egg in stool.
Human infected by ingestion metacercaria from infected sheep.
Diagnosis:
Stool analysis to find Fasciola egg.
General stage Trematoda
• Egg miracidium sporocyst
• (in snails )
• metacercaria cercariae Rediae
• (on water plants)
stages from Fasciola hepatica life cycle
Rediae
sporocystsMiracidium
Cercaria
Metacercaria
Morphology
Adult worms are large leaf-like, 20 to 30 mm in length.
At the anterior end, distinct conical projection is observed.
The ceca and testes are highly branched.
The eggs measure about 140 by 80 µm.
Morphology
Egg :eggs of fasciola hepatica, large, operculated, ovoid in shape contains a large un segmented ovum in amass of yolk cells, 130 – 150 X 63 – 90 µm, light brown to yellow ( bile stained ) from stool smear, duodenal aspirates.