Authors

R C Hoyle¹; D J Williams¹; J S Duncan¹; J E Hodgkinson¹;  ¹ Infection, Veterinary and Ecological Sciences, University of Liverpool, UK

Discussion

In the UK liver fluke (Fasciola hepatica) infection is a serious pathogen of sheep causing significant mortality due to acute fasciolosis; whilst chronic fasciolosis in cattle is a significant cause of morbidity. This results in substantial economic losses to livestock farmers, reduces efficiency of production systems and impacts negatively on livestock health and welfare. Rumen fluke (primarily Calicophoron daubneyi species) is considered to be an emerging parasitic infection of ruminant livestock across Europe. Liver fluke is well studied in the UK, but for rumen fluke the picture is still emerging. These parasites are often present as co-infections, but the only drug that has efficacy against rumen fluke is oxyclozanide. Despite increasing prevalence, little is known about awareness of rumen fluke amongst farmers in the UK or about current control practises in sheep and cattle. From December 2019 to March 2020, 453 sheep and/or cattle farmers completed an online questionnaire, capturing awareness and current control practices for both parasites.

The majority of respondents (70.28%) were aware of rumen fluke, with 13.90% recording its presence on farm and 18.32% having previously treated. Almost all respondents (98.89%) were aware of liver fluke and higher numbers reported its presence on farm (66.44%) and having previously treated (87.85%). Respondents were concerned about rumen fluke (81.07%), although they were less concerned about rumen fluke than liver fluke (p<0.05). Increased concern from both parasites was associated with presence on farm (p<0.05) or previous treatments (p<0.05). There are only two methods to detect rumen fluke (post-mortem or faecal egg count tests), but 42.85% of respondents who recorded rumen fluke presence on farm cited other diagnostic methods, traditionally used to detect liver fluke. Respondents were more likely to treat every year for liver fluke, as oppose to rumen fluke (p<0.05). Only 37.77% of cattle treatments and 26.51% of sheep treatments for rumen fluke in 2019 involved a product containing oxyclozanide (the only drug to show efficacy against rumen fluke). The most frequently used drug for liver fluke was triclabendazole. A small proportion (0.79%) used a non-flukicide in treating sheep for liver fluke. This new evidence demonstrates the confusion amongst farmers about these two parasites and their control, highlighting the need to raise awareness of rumen fluke and work to provide best practise advice for the control of both parasites in livestock.