Damage caused by liver fluke results in lost production, sometimes causes the death of animals and costs the UK agriculture industry up to £23m per year.

Exploring the issue at the National Beef Association’s Beef Expo NI in Dungannon on Monday, Maura Langan from Norbrook Laboratories said that one in five bovine livers in UK abattoirs are contaminated with liver fluke.

The veterinary adviser said that the major financial cost of liver fluke did not come from losses with fifth-quarter products in meat processing, but rather production losses on farms. Langan pointed out that the liver is the main organ needed for metabolism in cattle, so damage to it from burrowing by fluke affects metabolic processes.

“For beef farmers, chronic liver fluke (adult fluke infections) can cost up to £90 a head by delaying finishing by up to 27 days, reducing carcase weight by up to 10kg and reducing carcase conformation,” she said.

Feed intakes

Langan maintained that it can also reduce feed intakes by up to 15%, reduce body condition, lower milk yield in dairy cows by 8%, delay oestrus in breeding animals and leave all cattle more prone to infections.

Acute fluke differs from chronic fluke as it is caused by a heavy burden of early immature fluke and can cause sudden death in sheep. Langan said that cattle are less prone to acute fluke because their livers are larger and more fibrous.

“Treatments for fluke during the grazing season are not as well implemented as treatments during the housing period when cattle are not picking up any more fluke,” she said.

Langan advised that a treatment midsummer in cattle can lower fluke burdens the following winter as it reduces the number of fluke eggs going into the mud snail which acts as an intermediate host.

“Treatment regimes need to be tailored to your own farm. Resistance issues mainly relate to triclabendazole-based products as these products can cover all three lifecycle stages of fluke.

‘‘We should be preserving triclabendazole for sheep treatments as you are less likely to have losses from early immature (acute) fluke in cattle,” she said.

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