The relatively low and later incidence of liver fluke in recent years shouldn’t make sheep farmers complacent this autumn and winter, say the Sustainable Control of Parasites of Sheep (SCOPS) and Control of Cattle Parasites Sustainably (COWS) groups.
Speaking on behalf of SCOPS and COWS, Dr Philip Skuce of Moredun said: “Since 2018, a run of very dry springs and quite hot, dry summers has resulted in relatively low levels of liver fluke across most of the country. The low numbers of clinical cases and production losses in recent years could have lulled us into a false sense of security.
“This year is shaping up to be quite different. It was very wet in some places this summer and autumn has seen rainfall well above average. Although temperatures have been quite cool, they have generally been high enough to allow fluke stages to develop across the country.”
John Graham Brown of NADIS sits on both the SCOPS and COWS groups. He said the NADIS Liver Fluke Forecast encapsulates the main drivers of fluke risk, namely temperature and rainfall. The NADIS provisional autumn forecast is predicting a medium to high risk on the west coast, all the way from North Wales up to northern Scotland.
While elsewhere the risk is relatively low, he added a warning: “With the unpredictable weather patterns, it is difficult to say with certainty how this will translate into individual on-farm risk. It has been relatively wet and mild this year, so it is likely snail habitats, and therefore liver fluke, will 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 will be starting from a relatively low level, there is potential for the fluke population to build up this autumn into what is the traditional peak fluke season. Veterinary surveillance at the Animal & Plant Health Agency (APHA) supports this with reports of clinical cases of acute fluke since September.
“Testing remains the best option to cope with the unpredictability of fluke risk on an individual farm, avoiding treatments that are unnecessary or too early, while also making sure animals are treated in time to minimise any production losses. There is a SCOPS and COWS 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 SCOPS-COWS Guide to Test-Based Liver Fluke Control from SCOPS and COWS.