1. Veterinarian Konrad Przywara, 40A Grudzielskiego St., 63-700 Krotoszyn, Poland
2. Department of Epizootiology, Faculty of Veterinary Medicine, University of Warmia and Mazury, Oczapowskiego 13, 10-718 Olsztyn, Poland
3. Department of Large Animal Diseases with Clinic, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, 02-797 Warsaw, Poland
4. Laboratory of the Polish Society of Breeders and Producers of Fur Animals, Pocztowa St. 5, 62-080 Tarnowo Podgórne, Poland