1. National Marine Fisheries Research Institute, Kołłątaja 1, 81-332 Gdynia, Poland
2. Department of Preclinic Sciences and Infectious Diseases, Poznan University of Life Sciences in Poznan, Wołyńska 35, 60-637 Poznań, Poland
3. Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland
4. Department of Fish Diseases, National Veterinary Research Institute, Aleja Partyzantów 57, 24-100 Puławy, Poland