Fasciolosis (Fasciola hepatica)
Introduction
Fasciolosis is a trematode (fluke) disease of the liver and bile ducts caused by Fasciola hepatica. It is an economically important parasitic disease of ruminants and also has zoonotic significance. The disease is associated with liver damage, reduced productivity, and mortality in severe infections.
Etiology
Causative Agent
- Fasciola hepatica (common liver fluke)
- Fasciola gigantica (tropical regions)
Intermediate Host
- Freshwater snail (Lymnaea spp.)
Epidemiology
Species Affected
- Cattle
- Sheep (highly susceptible)
- Goats
- Occasionally humans
Transmission
- Ingestion of metacercariae on contaminated pasture
- Requires wet, marshy environments
Pathogenesis
Migration Phase
Immature flukes migrate through liver parenchyma causing tissue destruction and hemorrhage.
Biliary Phase
- Adult flukes reside in bile ducts
- Cause cholangitis and biliary obstruction
Clinical Signs
- Weight loss
- Anemia
- Submandibular edema (“bottle jaw”)
- Reduced milk/wool production
Diagnosis
- Fecal sedimentation (eggs)
- Serology
- Liver enzymes elevation
Treatment
- Triclabendazole (effective against immature and adult flukes)
Control
- Snail control
- Pasture management
- Strategic deworming
Home