New batch test aids detection of liver fluke

A much cheaper means of checking whether herds are infected with the liver fluke parasite Fasciola hepatica has been evaluated by the NSW Department of Primary Industries.

Graziers spend an estimated $20 million a year on chemical treatments to control liver fluke, a parasite which is endemic in pastures grazed by up to 40 million sheep and 6 million cattle nationally.

NSW DPI researchers at the Elizabeth Macarthur Agricultural Institute recently determined a reliable way of using the commercial Fluke ELISA test on pooled blood samples.

Instead of having to test individual animals, five samples are pooled. The cost of the pooled test is $24.05 ($19.05 for a single sample plus $5 pooling fee), a saving of about $53 on the cost of testing five animals from individual blood samples.

According to the manager of NSW DPI’s Diagnostic and Analytical Laboratory, Mr Greg Stevens, the test is sufficiently accurate to detect infected herds, even if just one animal in the pool carries antibodies to the infection.

Liver fluke is estimated to result in 5 percent average loss of production in cattle and sheep. Other significant losses in sheep include: reduced production and quality of wool, reduced lambing percentages, poor growth rate of lambs and increased costs for replacement stock

In cattle, the losses include: reduced production and quality of milk, lower growth rates and lower feed conversion rates in fattening cattle.

Fasciola hepatica infection is widespread across eastern New South Wales in areas where the annual mean rainfall is about 600 mm or more. Infected areas include the Tablelands and nearby slopes.