UK - A project looking into liver fluke prevention has made progress on early detection and likely habitats of disease vectors, and will now look into the economic impact on cattle, according to AHDB Beef & Lamb Livestock Scientist Mary Vickers.
Fluke is a growing issue for farmers. The parasite thrives in wet, muddy conditions and the UK’s changing climate, with higher rainfall and milder winters, is adding to the problem. But farm-specific factors can also play an important part in whether herds are affected.
Surveys show that liver fluke is present in as much as 80 per cent of the national dairy herd, and a recent study of high-yielding dairy herds suggested that high fluke herds produce 1,100kg milk per cow per lactation less than low fluke herds. A similar negative financial impact has been demonstrated in the beef and sheep industries from this parasite.
The project work, led by the University of Liverpool, has so far centred around early detection and identifying where the parasite is most likely to be found.
Work is currently under way to provide specific details of the best, most cost-effective way to monitor herds for infection. The Moredun Research Institute has suggested that composite egg counts are the best way of identifying infected herds.
Secondly, the Centre for Ecology and Hydrology has shown that more snails, the parasite’s vector, are found in unimproved pasture, particularly where rushes and water flushes are found. The work also found that, on the test farms, cattle spend most time grazing pasture containing sparsely distributed rushes, however dung tends to be dropped in wet flush and water bodies, where snails are more prevalent.
In 2014, in order to identify factors that increase a farm’s risk of fluke infection, 200 farms in Shropshire had their cattle sampled and completed a detailed questionnaire on farm management, pasture use and other relevant information. Of the farms tested, 42.5 per cent were fluke positive by composite egg count. 2014 was considered to be a relatively low risk year for fluke, showing just how common fluke is in UK cattle herds.
The final component of the project involves estimating the economic impact of fluke on the UK cattle industry. Scotland’s Rural College (SRUC) researchers have developed herd-level models to estimate comparative losses in different management systems.
Dairy herd losses are the highest, with the loss per infected cow per year being in the range £162-£224, compared to a fluke-free cow. Spring/summer calving suckler herds have higher losses per infected cow than autumn/winter calving herds.
Higher losses are also experienced for growing heifers originating from suckler herds than from dairy herds. These models will be used later to evaluate potential control measures and the net benefits of improved control of fluke.TheCattleSite News Desk