The liver fluke is a highly pathogenic flatworm parasite that causes significant disease and production losses in grazing animals. Because it has a mud snail intermediate host, liver fluke is typically found on low-lying, boggy or ‘fluky’ ground. Some agri-environment schemes promote the introduction or retention of wetland areas on-farm for a variety of environmental benefits associated with these habitats. There is, understandably, a perception amongst farmers that this might increase the liver fluke risk to their livestock, but there is very little evidence as to whether this is a good or bad idea.
To investigate this, we have been evaluating the fluke risk to livestock under two different agri-environment scheme scenarios. Firstly, on the Caerlaverock Estate, Solway Firth, where livestock grazing is required to provide the optimum habitat for natterjack toads, a protected species in Scotland and, secondly, at SRUC’s Hill and Mountain Research Centre, Kirkton and Auchtertyre Farms near Crianlarich, Perthshire, where we have been monitoring wader scrapes established to encourage wetland birds, such as snipe, curlew, oystercatcher, which are in serious decline in Scotland.
Under both scenarios, we determined the liver fluke infection status of sentinel animals grazing these areas, based on faecal egg counting (FEC) and determined the presence, species identification and fluke infection status of mud snails collected on-site using a PCR/sequencing approach. Results would indicate that the fluke risk to grazing livestock under these specific grazing scenarios was actually relatively low, but requires ongoing monitoring and management. We now hope to extend this study to investigate fluke risk under other environmental schemes, such as woodland and peatland habitats.
This study illustrates that it is possible to promote biodiversity benefits through conservation grazing, and not at the expense of animal health, but this requires evidence and informed decision-making. Both scenarios now feature as case studies, along with key information on sustainable fluke control and other environmental considerations, in our new Moredun Foundation ‘Fluke risk and conservation grazing – a guide to good practice’, which was published in November.
For more information, please contact Philip Skuce philip.skuce@moredun.ac.uk