1. 1 Department of Ichthyology and Aquaculture, Faculty of Animal Bioengineering , University of Warmia and Mazury , Olsztyn , Poland
2. 2 Department of Ichthyology, Hydrobiology and Aquatic Ecology , National Inland Fisheries Research Institute Olsztyn , Poland
3. 3 Department of Research and Development , Chemprof, Gutkowo, 11-041 Olsztyn , Poland