1. Institute of Marine Research (IMR) Reproduction and Developmental Biology, , Matre Research Station, 5984 Matredal, Norway
2. Institute of Marine Research (IMR) Pathogens and disease transfer, , PO Box 1870, Nordnes, 5817 Bergen, Norway
3. Institute of Marine Research (IMR) Reproduction and Developmental Biology, , PO Box 1870, Nordnes, 5817 Bergen, Norway