Sheep and cattle in some areas of the UK may face an earlier risk of acute liver fluke this winter than in previous years, with APHA already reporting cases.
Persistent wet weather this year has accelerated the emergence of acute fluke cases in certain regions, according to a leading sheep expert.
Independent sheep consultant Nerys Wright has emphasised the importance for farmers to regularly monitor for fluke to assess the specific risk to their farms.
She said this year's fluke season would be longer, and the risk would likely differ compared to previous years due to the weather.
This made monitoring for clinical signs, like poor performance and weight loss, as well as testing, even more critical.
"Sheep don’t develop immunity to fluke and no treatment has a persistent effect, so she stresses that if a farm has previously been affected by fluke, managing fluke risk is essential," Ms Wright said.
“You don’t want to treat too early if the risk isn’t present on your farm, as you may have to treat again later in the season.
"Similarly, you don’t want to treat too late and have production losses or even death. It’s important to monitor and test regularly during the risk period."
Mrs Wright outlines several testing options for fluke, including asking vets to post mortem ewes or lambs that die at this time of the year.
And a blood antibody ELISA test shows whether a sheep has been exposed to liver fluke and is most effective for first-grazing season animals, such as ewe lambs.
However, using faecal fluke egg count can only detect liver fluke when egg-laying adults are present.
Mrs Wright said: “Speak to your vet or animal health advisor who knows your farm about testing and treatment options, as it is difficult for advisers to know what to do or when to act without understanding what is happening on your farm.”
Zoetis vet Patricia van Veen added that that treatment choice would depend on whether the disease risk was caused by adult fluke, immature or early immature fluke migrating through the liver.
"Flukicides have varying efficacy for early/ late immature and mature fluke, so it’s essential to understand what you’re dealing with and consult your animal health advisor for the best treatment option.
"Oral triclabendazole formulation has the highest efficacy in the early immature fluke stages," she explained.
"In addition to treatments, managing ongoing risk by avoiding high-fluke risk fields, or even areas within fields, is essential to minimise production losses from acute fluke in autumn."
What are the testing options for fluke?
Nerys Wright has outlined several testing options for fluke:
• Post Mortem: Asking your vet to post mortem ewes or lambs that die at this time of the year, is an opportunity to look at the livers and bile ducts for evidence of acute or historical fluke.
• Blood Antibody ELISA Test: This shows whether a sheep has been exposed to liver fluke and is most effective for first-grazing season animals, such as ewe lambs.
• Coproantigen ELISA Test: Conducted on dung samples, this test is useful in late autumn/winter to detect mid- to late-stage infections. It generally provides two to three weeks warning compared to a faecal egg test.
• Faecal Fluke Egg Count: This can only detect liver fluke when egg-laying adults are present.
• Abattoir feedback: If you send lambs or cull ewes direct to slaughter, asking for feedback on the livers is valuable information about historic infections, highlighting how well fluke is managed on your farm.
