Livestock farms in the wetter parts of the country will be aware of the damage liver fluke can cause. However, even where the impact on sheep flocks is visible (ie deaths from acute fluke disease), the impact on productivity for both beef and dairy herds, and the impact of subclinical disease in the sheep flock, is often under-estimated.
For example, beef animals with 10 or fewer fluke in the liver will take on average 31 days longer to finish.1 However, maintaining a high level of liver fluke control is not straightforward.
The seasonal lifecycle, the requirement for the intermediate host, the mud snail, and total dependence on weather conditions of both the mud snails and the environmental stages of the fluke, make the timing and level of fluke challenge extremely variable year to year and farm to farm. Additionally, the fact not all liver fluke products will kill all the stages of fluke in the animal, means routine treatments according to calendar dates will often miss the target, either treating too early before there are any fluke present, treating too late so the damage is already done, or simply using a product that does not kill the stages of fluke present at the time of treatment.