1. 1 Department of Morphological Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences , 02-776 Warszawa , Poland
2. 2 Department of Animal Physiology and Biostructure, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences , 51-631 Wrocław , Poland
3. 3 Division of Veterinary Epidemiology and Economics, Institute of Veterinary Medicine, Warsaw University of Life Sciences , 02-776 Warszawa , Poland
4. 4 Department of Preclinical Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences , 02-786 Warszawa , Poland
5. 5 Department of Normal and Clinical Anatomy, Medical University of Lodz , 90-752 Łódź , Poland