Conditions when likely to occur: Previous history on property but there are many farms where infection is not recognised and is causing production losses. A blood test is required to detect antibodies in combination with faecal egg counts.
Presence of fluke snail (L. tomentosa) on property.
Cattle and sheep have grazing access to springs, swampy areas, water courses and irrigation.
Acute fluke disease: Usually from early summer to late autumn.
Chronic fluke: Any time, but typically late summer to winter.
If no effective control program in place, clinical disease is more likely, especially in cattle less than 18 months of age. Animals suffering from liver fluke disease may not show any obvious symptoms and deaths account for only part of lost production in cattle. Other symptoms are associated with ill thrift and include reduced production and quality of milk, lower growth rates and lower feed conversion rates in growing cattle. History on property, individual paddock.
Clinical signs: Bottle jaw, scouring weight loss.
Management strategy to treat and prevent disease:
- Strategic: Drenching with Triclabendazole in late autumn and early winter to kill all fluke picked up over summer and autumn. Early spring treatment to remove adult infections missed by the autumn/winter treatment. This will prevent contamination of snail habitats for the next year. Other cheaper chemicals can be used for this treatment including injectable products. Late summer drench may also be required in high-risk situations or where monitoring indicates the presence of infection, particularly with animal less than 15 months.
- Early drenching with triclabendazole may be required.
Drench with triclabendazole if risk assessment indicates likely infection.
Faecal egg counts indicate presence of adult fluke – most valuable in young animals.
See the MLA catte parasite atlas (a regional guide to cattle parasite control in Australia) for more information on liver fluke and other typical parasites affecting cattle, including advice on selecting a worm drench and safe pastures.
More information on liver fluke including causes, prevention and treatment can be found on the primefacts factsheet provided by the NSW Department of Primary Industries.