Печёночная двуустка, или обыкновенная фасциола (лат. Fasciola hepatica) — вид плоских червей из классатрематод (Trematoda). Паразиты со сложным жизненным циклом, включающим партеногенетические игермафродитное поколения. В качестве хозяина для партеногенетических поколений печёночной двуустки обычно выступают малые прудовики (Galba truncatula). Гермафродитное поколение (мариты) обитает в печени, жёлчном пузыре и его протоке у млекопитающих, как правило, домашних копытных (коров и овец), иногда происходит заражение человека. Вызываемое маритами заболевание — фасциолёз

The following table states how many times the liver fluke fasciola hepatica have been identified during official post mortem inspection and prevented from entering the food chain by officials working for and on behalf of the Food Standards Agency (FSA) since April 2012:

The data for sheep, goats, deer and horses is from April 2012 to December 2013 all other species is April 2012 to March 2014.

Liver fluke is a common parasitic disease of both cattle and sheep in the United Kingdom, caused by the parasite Fasciola hepatica, and is estimated to cost the cattle industry £23 million annually (source: National Animal Disease Information Service). In cattle, infection is more commonly encountered in beef cows grazing poor wet pasture but disease can be seen in dairy cattle especially after summering cattle, most likely bulling heifers, away from home on infested pastures.

Where this condition is seen in liver from cattle or sheep presented for slaughter, results are fed back to the farmers as part of the FSA's collection and communication of inspection results, allowing farmers to organise treatment of their herds against liver fluke, and improve future yield. The figure for April 2010 to April 2012 has been included for reference.