1. Department of Epizootiology and Clinic of Bird and Exotic Animals, the Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Wroclaw, Poland.
2. Sovon Dutch Centre for Field Ornithology, Nijmegen, the Netherlands.
3. Institute of Genetics and Microbiology, the Faculty of Biological Sciences, the University of Wroclaw, Wroclaw, Poland.