Liver fluke (F. hepatica) antibody (milk)

Interpretation of Fasciola hepatica Bulk Milk (ELISA) Results
</= 30% - No or very low level of seropositive animals contributing to the bulk tank
>30% to </=80% - Fewer than 20% of cows contributing to the bulk tank are seropositive
>80% to <150% - Between 20% and 50% of cows contributing to the bulk tank are seropositive.A bulked faeces sample for the detection of fluke eggs can be used to confirm current infection within the herd
>/=150% - More than 50% of cows contributing to the bulk tank are seropositive. A liver fluke control programme should be implemented as part of a herd health plan.

When interpreting the bulk tank antibody result it should be recognised that an individual animal will become positive for antibody from two weeks after exposure to the parasite and antibody will persist for up to ten months after exposure to the parasite has ceased. To confirm the presence of patent infection in the herd faecal examination for F hepatica eggs from ten animals is recommended. The samples can be combined at the laboratory and tested as a bulk sample.