Liver fluke (Fasciola hepatica L.) in dairy cows in North-East Poland

Investigations were carried out on 993 cows in 14 breeding farms in 1998-19 99. In 871 cows feces from rectum were collected and examined in the labora tory; eggs of Fasciola hepatica were detected in 36, that is 4.13%. The mos t extensive invasion of fasciolosis was observed in dairy cows from the Mys zyniec area (20%) and in farms in the north-east Olsztyn area (8.7-16.7%); the lowest prevalence was observed in the west of the Olsztyn area (2.2-3.3 %), In 6 (42.8%) out of 14 investigated farms liver fluke was not observed. The research showed that the significantly decreased extensive invasion of Fasciola hepatica in dairy cows in North-East Poland was not caused by syst ematic treatment, but was influenced by environmental indicators, mostly fr om acidity of water, where miracidiums die and snails - intermediate hosts of Fasciola hepatica - do not develop.