1. Department of Animal Molecular Biology , National Research Institute of Animal Production , 32-083 Balice n. Kraków , Poland
2. Department of Cattle Breeding , National Research Institute of Animal Production , Balice n. Kraków , Poland
3. Faculty of Biology and Environmental Protection , Nicolaus Copernicus University , Toruń , Poland
4. Department of Pig Breeding , National Research Institute of Animal Production , 32-083 Balice n. Kraków , Poland