Wet weather during the summer months has resulted in an increased risk of liver fluke and the Liver Fluke Advisory Group this week advised farmers to be vigilant in relation to the disease. Where cattle are routinely housed on farms in late autumn, the timing of the administration of the fluke dose after the animals are housed depends on the type of flukicide used. However, on farms where cattle are kept outdoors on pasture for the winter, treatment should be carried out immediately and these animals may also need a further treatment in the new year. Treatment of dairy cows for liver fluke is best carried out after drying off and not during lactation. As regards sheep, the advice is that they should be dosed now especially on those farms with a history of liver fluke. In general, further treatments, usually in January and April, are necessary for sheep that are out-wintered. All bought-in cattle and sheep should be kept isolated and dosed with an anthelmintic and flukicide before being allowed to join the main herd or flock. The Advisory Group has also advised that farmers should submit faecal samples from a representative number of treated animals (not less than 5) to the Department’s local Regional Veterinary Laboratory at least three weeks after treatment to check efficacy of the anthelmintic used. The Department indicated that the foregoing information is based on a disease forecast model that uses weather data collected during the summer and autumn at Met Éireann weather stations across the country. Information on the liver fluke situation in Northern Ireland, contained in the Liver Fluke Forecast 2007 issued by the Agri Food and Biosciences Institute, Northern Ireland was also used.