1. Department of Histology and Embryology, Poznan University of Medical Sciences, 6 Święcickiego St., 60-781 Poznań, Poland
2. Department of Anatomy, Poznan University of Medical Sciences, 6 Święcickiego St., 60-781 Poznań, Poland
3. Department of Obstetrics and Gynecology, University Hospital and Masaryk University, Obilni trh 11, 602 00 Brno, Czech Republic
4. Department of Anatomy and Histology, Faculty of Medicine and Health Sciences, University of Zielona Gora, Ul. Zyty 28, 65-046 Zielona Gora, Poland
5. Institute of Veterinary and Animal Science, Poznan University of Life Sciences, 52 Wojska Polskiego St., 60-628 Poznań, Poland