EN
The aim of the study was to determine the prevalence of infection with gastrointestinal parasites in Polish Konik horses from Poland and those imported from the Netherlands. The prevalence and rate of infection was determined based on coproscopic examination using Willis-Schlaf and Mc-Master methods. Faecal samples were tested for the presence of Cryptosporidium sp. using a modified Ziehl-Neelsen staining method. Mean prevalence of infection with gastrointestinal parasites in Polish Koniks imported from the Netherlands and those from Poland was 100%. Imported horses were found to harbour nematodes of the family Strongylidae (89.47%) and Cyathostominae (94.74%) as well as Parascaris equorum (5.26%) roundworms. Domestic Polish Koniks were found to harbour Strongylidae (100%) and Cyathostominae (100%) nematodes as well as Cryptosporidium sp. protozoa (2.27%). Domestic horses were more infected with Cyathostominae (865 EPG) and Strongylidae (731 EPG) than horses imported from the Netherlands (739 and 600 EPG, respectively). The study demonstrated that Polish Koniks from Poland and those imported from the Netherlands should be monitored parasitologically because endoparasites may create a major epizootiological problem when these animals are kept in an organic production system.