North Coast cattle producers urged to monitor for liver fluke
North Coast Local Land Services District Veterinarians are reminding cattle producers to be on alert for liver fluke, following recent testing that has revealed significant cases of the parasite causing ill thrift in local herds. Liver fluke is a costly parasite that reduces productivity and animal health, and timely treatment is critical to break the cycle and reduce pasture contamination.
Liver fluke (Fasciola hepatica) is common in eastern New South Wales where rainfall exceeds 600 mm. Untreated infestations can cause major production losses in sheep and cattle, and while the parasite can also infect goats, horses, kangaroos and even humans, clinical disease is rarely seen in these species.
The parasite relies on aquatic snails as an intermediate host. These snails inhabit swampy or slow-flowing areas such as streams, seepages and irrigation channels. Wetter conditions over the last couple of years have favoured snail populations, leading to increased pasture contamination with liver fluke cysts. Once ingested by cattle, the immature parasites migrate to the liver where they develop into adults.
Phil Carter, District Veterinarian with North Coast Local Land Services, said liver fluke distribution across the region is patchy but cases are increasing.
“Surveys from the 1970s, as well as recent testing, suggest many areas - particularly in the south of the region - remain free of liver fluke. It’s a worthwhile investment to establish the fluke status of your property, as many areas of the North Coast are unsuitable for the parasite and its snail host. Testing before treating can save producers money and help target control more effectively,” he said.
Acute liver fluke infections may cause no obvious symptoms or, in severe cases, result in haemorrhage and death. Liver fluke is also an indirect cause of Black Disease, an acute and often fatal condition of cattle that can be prevented through correct administration of the 5-in-1 vaccine.
The most significant impacts are seen with chronic infections, where cattle show progressive weight loss, weakness and anaemia caused by blood-feeding adult flukes in the bile ducts. Clinical signs include pale mucous membranes and, in some cases, the classic “bottle jaw” swelling beneath the jawline. In dairy herds, liver fluke can reduce both milk yield and quality, while in beef herds infestations may exacerbate the demands of late pregnancy and result in weak calves from undernourished cows.
Phil said producers should take an integrated approach to management. “If you have confirmed infestations, combining chemical treatments with grazing and management strategies will reduce the risk of production losses, save money, and limit resistance pressure on drenches,” he said.
For more information on testing and control options, contact your North Coast Local Land Services District Veterinarian on 1300 795 299.
Media Contact
For more information, please contact Michelle Gapes, Regional Communications Advisor, North Coast/Hunter via email michelle.gapes@lls.nsw.gov.au or 0467 291 890