1. 1 Department of Gamete and Embryo Biology , Institute of Animal Reproduction and Food Research, Polish Academy of Sciences , Olsztyn , Poland
2. 2 Private veterinary practice Arkadiusz Nowicki , Olsztyn , Poland
3. 3 Department of Obstetrics and Gynecology Nursing , Medical University of Gdansk , Gdańsk , Poland
4. 4 Invicta Research and Development Center , Sopot , Poland