The relatively low and later incidence of liver fluke in recent years should not make cattle and sheep farmers complacent this autumn and winter, say the Control of Worms Sustainably (COWS) and Sustainable Control of Parasites of Sheep (SCOPS) groups.
Speaking on behalf of COWS and SCOPS, Dr Philip Skuce of Moredun says: “A run of very dry springs and quite hot, dry summers since approximately 2018 has resulted in liver fluke incidence being relatively low and late across most of the country. This has maybe lulled us into a false sense of security, with relatively few clinical cases and production impacts as a result.
“This year is shaping up to be quite different, as it was very wet in places this summer, with rainfall well above average (not to mention what has happened since we’ve gone into autumn). This has varied hugely across the country and across the year, as has temperatures which, although relatively cool, have mostly still been warm enough to allow fluke stages to develop.”
Fluke risk is driven largely, but not exclusively, by prevailing weather conditions, most notably temperature and rainfall. This is encapsulated in the NADIS Liver Fluke Forecast
John Graham Brown of NADIS sits on both the COWS and SCOPS groups. He says the provisional autumn risk forecast from NADIS is predicting a medium to high risk on the west coast from North Wales up to northern Scotland, but relatively low risk everywhere else.
But he adds a word of warning: “With the weather patterns being as unpredictable as they are it is difficult to say with much certainty how this will translate to on-farm risk. It has been relatively wet and mild this year so it is likely snail habitats, and therefore liver fluke, is going to be more widespread on farms than in previous dry summers. The mantra of ‘test don’t guess’ is going to be key.”
Dr Skuce supports this view: “Although liver fluke incidence will be starting from a relatively low level on many farms, there is potential for the level to build up at this time of year, in what was the traditional peak fluke season. Indeed, veterinary surveillance services at the Animal & Plant Health Agency (APHA) have been reporting clinical cases of acute fluke since September.
“Testing remains the best option to understand the fluke risk on any given farm, especially when the fluke risk has been so unpredictable. There is a COWS and SCOPS guide to the liver fluke tests available and how best to deploy them. Routine testing will help you make informed decisions around the need to treat, the best product to use and also how well that treatment has worked, all of which will help in the sustainable control of liver fluke on-farm.”
Find the COWS-SCOPS Guide to Test-Based Liver Fluke Control: https://www.cattleparasites.org.uk/app/uploads/2022/12/FINAL-Fluke-Diagnostics-Treatment.pdf
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