1. Department of Histology and Embryology, Faculty of Veterinary Medicine; Wrocław University of Environmental and Life Sciences; ul. Norwida 25/27; 50-375; Wrocław; Poland
2. Department of Epizootiology and Clinic of Bird and Exotic Animals, Faculty of Veterinary Medicine; Wrocław University of Environmental and Life Sciences; pl. Grunwaldzki 45; 50-366; Wrocław; Poland