1. From the Department of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences Brno, Czech Republic, Palackeho 1/3, CZ-612 42, Brno, Czech Republic. Dr. Kyllar is also at the Institute of Anatomy, Histology and Embryology, University of Veterinary and Pharmaceutical Sciences, Brno