Affiliation: | 1. Department of Epizootiology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, St. Oczapowskiego 01/29, 10-718 Olsztyn, Poland;2. Boehringer Ingelheim Sp. z o.o., St. Wolska 5, 02-675 Warszawa, Poland;3. Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 13/29, 10-718 Olsztyn, Poland |