Liver Fluke Diagnostics

Fasciola hepatica - liver fluke diagnostics

Liver Fluke Diagnostics

A significant cost for farmers

Liver fluke (Fasciola hepatica) are trematode parasites responsible for the disease fasciolosis, mainly seen in sheep and cattle. They use snails as an intermediate host, so are usually more prevalent on land that doesn’t drain well and during wet summers. Infective larvae can survive on pasture for several months.

Prevalence of the disease is increasing, possibly due to changes in climate and farming practises, an increase in animal movement around the UK and the increase of AR in fluke.

Infection is caused by immature fluke migrating through the liver, by adult worms present in the bile duct, or both. The disease causes considerable economic loss to farmers in the UK and worldwide.

Liver fluke can also affect the susceptibility to and diagnosis of other diseases, including bovine tuberculosis. It is estimated that one third of cases of bovine tuberculosis in England and Wales go undiagnosed due to the decreased sensitivity of tests used in infected cattle.

For this reason, along with the economic implications of fluke infections, control of this parasite is of utmost importance.

The impact of liver fluke

Symptoms associated with liver fluke infection are related to the stage of disease:


  • Gradual weight loss
  • Loss of appetite
  • Anaemia
  • Ascites (build-up of fluid between the two layers of the peritoneum)
  • Submandibular swelling (“bottle jaw”)
  • Diarrhoea
  • Reduced milk yield (cattle)


  • Rapid weight loss
  • Jaundice
  • Depression
  • Submandibular swelling
  • Ascites
  • Anaemia
  • Poor fleece quality (sheep)


  • Ascites
  • Abdominal pain
  • Dullness and lethargy
  • Sudden death
  • Difficulty breathing
  • Anaemia

How to control liver fluke

The best control strategy is a two-pronged approach that combines the use of flukicides with effective grazing and herd management. Any control strategy should always be carried out under the guidance of your veterinarian.

How to diagnose liver fluke

Methods to diagnose liver fluke infections in livestock include:

  • Worm egg counts (WEC)
  • Faecal antigen test

We provide WECs to identify the specific fluke parasite and help you accurately target treatment.

We also carry out in vitro ELISA tests to assess the effectiveness of a treatment and determine the correct dose. You can book a test and find more information here.