Wat zijn de mogelijkheden om een leverbotinfectie bij melkvee te voorkomen?

The analysis of risk factors and prevalence of liver fluke took place in the Netherlands, Denmark, Germany, and Lithuania. This is the report on the findings in the Netherlands. In the Netherlands, the liver fluke surveys are performed on 26 farms; 13 pairs of neighbouring positive and negative cattle farms have been identified based on liver fluke antibodies in bulk milk samples. It was stated that the outcomes of blood antibodies were not in line with bulk milk samples. Using bulk milk samples only to identify liver fluke farms will underestimate the prevalence of liver fluke. Blood sampling on all present on farm groups of animals is necessary for a good estimate of the prevalence of liver fluke. Therefore the risk factor analysis is performed with the remaining 8 pairs of neighbouring positive and negative cattle farms. (Economic) losses from liver fluke may consist of a lower milk yield, less and / or a delayed development of young stock, rejected livers, reduced fertility and resistance. In this research, no differences were found in average milk yield and the number required inseminations between positive and negative companies. However, there are more health problems (such as claw diseases) on the positive farms. Average knowledge about liver fluke (expressed in a score) showed no difference between positive and negative farms. However, at all negative farms, the farmers were aware of the liver fluke prognosis in their area and the risk factors. They also apply more preventative measures than positive farms, such as summer stable feeding, avoiding contaminated plots , increasing resistance of livestock, adapted ditch management and active dewatering. In this study the infected young stock was found to be treated incorrectly. As a result, they contribute to the infection build-up in the following grassland season. In short, clearly identified risk factors for liver fluke are wrong treatment of cattle and sheep including not being allowed to treat lactating animals grazing on parcels at risk. Preventative measures such as summer feeding and drainage provides a lower risk on liver fluke. A remarkable finding is that the salmonellosis prevalence is not higher on positive liver fluke farms. Promising preventative measures have been investigated, of which summer milling of trenches in order to decimate the Galba truncatula population and evasive grazing had both a positive influence on preventing/lowering the risk of liver fluke infection.