1. Department of Anatomy, Poznan University of Medical Sciences , Poznan , Poland
2. Veterinary Centre, Nicolaus Copernicus University in Torun , Torun , Poland
3. Department of Histology and Embryology, Poznan University of Medical Sciences , Poznan , Poland
4. Department of Obstetrics and Gynecology, University Hospital and Masaryk University , Brno , Czech Republic
5. Department of Toxicology, Poznan University of Medical Sciences , Poznan , Poland
6. Department of Histology and Embryology, Wroclaw Medical University , Wroclaw , Poland
7. Division of Anatomy and Histology, University of Zielona Gora , Zielona Góra , Poland