The impact of liver fluke infection on the welfare of horses
Norman Hayward Fund
Area of study
Investigator(s): Professor Diana Williams
Liver disease has severe implications for the welfare of horses and the underlying causes are often difficult to diagnose. The University of Liverpool is recognised internationally for its fluke research; having received enquiries about fluke infection in horses and, using a prototype diagnostic ELISA, seen a diagnostic rate of 16%. Undiagnosed liver disease is associated with deterioration of a horse’s condition over time, extensive diagnostic intervention including liver biopsies and frequently euthanasia when cause cannot be found and treated. Because so little is known about fluke in horses it is not normally considered as a cause of liver disease and there is a lack of advice on its diagnosis, treatment and prevention. This project aimed to raise awareness of liver fluke as a differential in cases of chronic liver disease and improve advice available to vets and horse owners, reducing the suffering and early euthanasia of affected horses.
This project also hoped to ascertain how common liver fluke infection is as a cause of unexplained liver disease in horses, define the clinical syndrome associated with liver fluke infection to help improve diagnosis, provide advice to vets and horse owners and generally raise awareness of liver fluke as a diagnostic differential in cases of chronic liver disease. This would allow earlier diagnosis and treatment making a significant contribution to reducing the suffering and early euthanasia of affected horses.
Their results show that liver fluke is a cause of liver disease and should be diagnosed differently in horses exhibiting clinical signs or blood test abnormalities consistent with liver disease. Furthermore 64% of infected horses had a history of co-grazing with ruminants, and so should be considered a risk factor. The study also showed fluke was an important parasite and is responsible for a proportion of cases of liver disease of an unknown cause. This supports the need for diagnostic testing of 'at risk' horses.