'Sting in the tail' warning as liver fluke threat lingers this winter
Livestock farmers are being urged to stay alert for liver fluke this winter, as experts warn there could still be a late-season surge despite low disease levels so far.
Specialists from Sustainable Control of Parasites in Sheep (SCOPS) and Control of Worms Sustainably (COWS) say recent cold weather may have slowed infections, but the risk has not disappeared and could increase as conditions turn milder.
The warning follows a review of laboratory test results, post-mortems and on-farm feedback from across the UK. While current losses linked to liver fluke remain low, advisers caution there may still be a “sting in the tail” later in the winter or early spring.
Dr Philip Skuce, of Moredun, said infection could still be present on higher-risk ground and escalate quickly if temperatures rise. He warned there may be “active infection on flukey areas which could quickly ramp up if we have a mild spell”.
Farmers were urged not to rely on earlier treatments, as protection does not carry through the season. “A treatment given in the autumn or early winter offers no protection against further infection,” Dr Skuce said, adding: “There is no such thing as an insurance policy”.
Post-mortem evidence this winter has shown little sign of liver fluke so far, but advisers stress this should not lead to complacency.
Ben Strugnell, of Farm Post Mortems, said: “I have seen very little evidence of liver fluke in post mortems so far this winter, but there is still plenty of time for the challenge to build and pose a threat.”
He said examining livestock deaths remained crucial, noting: “We will always check for evidence of liver fluke, so never waste a dead sheep”.
Further warnings came from advisers monitoring disease levels nationally, who said the lack of cases so far could be misleading.
“Our concern is that this lulls people into a false sense of security,” said Heather Stevenson of SAC. “We don’t want to see cases in late winter, or even early spring, because we’ve taken our eye off things.”
Rebecca Mearns, of APHA, said risk could increase when stock are moved onto different grazing, particularly land with a history of fluke.
“Even if stock have been treated previously, flukicides have no residual effect, so stock are vulnerable and should be monitored using the tests available,” she said.
The advice applies across grazing livestock, including sheep and cattle, especially on farms operating mixed systems or using wetter ground.
SCOPS and COWS continue to urge farmers to base treatment decisions on evidence rather than routine dosing. As January progresses, faecal testing methods such as coproantigen testing or fluke egg detection are considered most appropriate in many cases.
Advisers recommend discussing testing strategies with a vet or animal health adviser to ensure results are interpreted correctly and treatments are used only when needed.
Experts warn that it is late winter complacency, rather than early-season infection, that poses the greatest risk, with undetected fluke capable of causing problems well into early spring.
