1. Department of Reproduction, Obstetrics, and Herd Health; Faculty of Veterinary Medicine, Ghent University; B-9820 Merelbeke Belgium
2. Animal Sciences Unit; Institute for Agricultural and Fisheries Research (ILVO); B-9090 Melle Belgium
3. Department of Reproductive Medicine; University Hospital, Ghent University; B-9000 Ghent Belgium
4. Laboratory for Pharmaceutical Biotechnology; Ghent University; B-9000 Ghent Belgium
5. Laboratory of Animal Genetics; Faculty of Veterinary Medicine, Ghent University; B-9820 Merelbeke Belgium