How to diagnose liver fluke in cows.
Liver fluke is estimated to cost the UK cattle industry around £23 million annually and with many herds being turned out onto fresh pasture over the coming weeks it’s important to assess the risk of liver fluke in your area1.
Vet Iain McCormick, of Galedin Vets, shares his advice for preventing liver fluke at turnout.
“We are seeing the incidence of liver fluke increase and following a particularly wet and mild winter it’s essential you know how to spot it and prevent it.
“Liver fluke eggs hatch in damp, warm conditions so cattle grazing in wet areas with soil temperatures above 10 degrees are at higher risk.
“The infective stages pass through tiny mud snails, emerging to climb up the grass ready to infect grazing cattle. Cattle grazing near snail habitats such as the edge of streams and rivers, and even muddy tractor ruts, are therefore at highest risk.
“If your cattle are at risk, you should test your herd by using faecal egg counts or ELISA tests in conjunction with abattoir feedback to spot any signs of liver fluke being present.
“If liver fluke is found, cattle should be treated appropriately and moved to less risky pasture,” says Iain.
Iain explains symptoms of liver fluke are often not recognised as easily in cattle as they are in sheep.
“Symptoms of liver fluke in cattle can often be misdiagnosed and neither cattle nor sheep
develop immunity to liver fluke, so it’s important to control infection in all ages of stock.
“To do this effectively you should discuss treatment options with your vet and develop an integrated farm approach to parasite control as part of your wider herd health plan,” says
Due to concerns over anthelmintic resistance Iain stresses that you should consider using triclabendazole-containing products on a case-by- case basis and always take into account the following factors when developing a parasite control plan with your vet:
For more information about liver fluke and to view the NADIS parasite forecast visit: www.nadis.org.uk/parasite-forecast
|Abattoir feedback||Requesting feedback when an animal is sent to slaughter can help identify if liver fluke is present in the liver and if any damage has been caused even if liver fluke is no longer present|
|Faecal samples||Dung samples can be used to detect liver fluke eggs and a minimum 50g sample is required. Be aware that liver fluke eggs are shed intermittently so dung samples can give false negative results|
|ELISA tests||Serum or milk samples can be used to detect antibodies using an ELISA test, usually detected two to three weeks after infection. Antibodies can persist for a period after treatment, therefore the test
does not prove liver fluke infection is currently present, just that the cow has been infected in the past
www.nadis.org.uk/bulletins/liver-fluke- control-in- cattle.aspx