‘Testing over treating’ livestock for liver fluke found effective in recent study
4th April 2023
A seasonal study, carried out on Islay as part of the RHASS Presidential Initiative (PI), has demonstrated that treating livestock ‘as little as possible, but as much as necessary’ for liver fluke can deliver a multitude of benefits for both animal and environmental health.
Highland cattle grazing on Islay, Inner Hebrides, Scotland.
Treating sheep and cattle for liver fluke at set intervals has led to overuse of treatments, increased resistance to the products left in a veterinary toolkit, and greater costs to farmers and the environment which could be mitigated through testing.
The fourth in a series of ten cases studies, featuring as part of this year’s RHASS PI, will look at how a project involving Moredun Research Institute, Elanco Animal Health, RSPB and Islay farmers has come up with a plan to boost animal welfare, reduce flukicide resistance, improve soil health and help enhance local wildlife populations.
Monthly monitoring of blood and faecal samples from a select group of animals revealed that the timing of liver fluke infection has changed, in part due to changing weather patterns. Nonetheless, many farmers are still prophylactically treating their livestock with flukicides, often unnecessarily.
This practice is not only leading to increased resistance to the remaining products effective against liver fluke, but is also causing chemicals to leach into surrounding soil and dung, potentially impacting wildlife.
One farmer involved in the study, Stuart Lamont, had been routinely treating sheep on his farm, but since testing showed very low levels of fluke in the summer and autumn, he was advised not to treat until January. Seeing the benefits, he has since switched to a testing over treating programme.
“By listening to the science, we have been able to make informed decisions about when to treat our livestock, which has led to benefits for animal welfare, as well as significant chemical savings,” he said.
“I’m now not having to unnecessarily handle my sheep to run them through a race every six weeks and by treating more sparingly, it means the products are more likely to work when we need to use them.”
Moredun Parasitologist, Philip Skuce, added that there is a careful balance to be struck between responsible treatment and conserving biodiversity on farm.
“On Islay, we were looking at how we could ensure optimal treatment for livestock whilst also addressing issues around product resistance, improving soil health, and supporting local wildlife,” he said, highlighting the important role science plays in providing evidence that a practice is safe for farmers to do.
“There is increasing pressure on the agricultural industry to reduce chemical usage and the most simple and effective way to do this is to ‘test, don’t guess’ and with patterns of parasite epidemiology shifting, more than ever scientists need to be monitoring these changes and bringing farmers along with us,” he stressed.
Commenting on the work, RHASS President Ian Duncan-Miller said: “The application of science to an everyday problem on Islay has shown a quite remarkable breadth and diversity of gains, and shows how really understanding the long-standing challenges will lead to benefits across the board.
“On a wildlife reserve, the priority is obviously the naturally occurring creatures, and this research has demonstrated the importance of science around the grazing livestock to the plants and other animals.”
For more information on this year’s initiative and to access past and future case studies, visit: https://rhass.org.uk/presidential-initiative/https://rhass.org.uk/presidential-initiative/
