1. Department of Preclinical Sciences and Infectious Diseases , Poznan University of Life Sciences , Poznań , Poland
2. Department of Histology and Embryology , Poznan University of Medical Sciences , Poznań , Poland
3. Department of Anatomy , Poznan University of Medical Sciences , Poznań , Poland
4. Department of Obstetrics and Gynecology , University Hospital and Masaryk University , Czech Republic
5. Veterinary Center , Nicolaus Copernicus University in Torun , Toruń , Poland
6. Division of Histology and Embryology, Department of Human Morphology and Embryology , Wroclaw Medical University , Wrocław , Poland
7. Division of Anatomy and Histology , University of Zielona Gora , Zielona Góra , Poland