Matvienko N. Biological properties of RNA viruses of fish in freshwater aquaculture of Ukraine.

The thesis research is devoted to the study of the biological properties of fish RNA viruses circulating on the territory of Ukraine. For the first time in Ukraine, the occurence of the most dangerous viruses, which affect major fish species of freshwater aquaculture, has been studied in different regions using modern virological and molecular-biological methods. For the first time in Ukraine, IPNV isolates were isolated from rainbow trout in aquaculture facilities of different forms of property in Western regions of Ukraine (Volyn, Lviv, Zakarpattya, Chernivtsy regions). These isolates have high pathogenicity to rainbow trout fry. The performed studies found that FHM, RTG-2, BF-2 cell cultures are suitable for reproduction and accumulation of infectious pancreatic necrosis virus. The virus is actively reproduced in these systems resulting in typical CPD. At the same time, viral infectious titer was 106.8-7.2 TCD50/cm3. Experiments showed that optimal culture for the accumulation of trout hemorrhagic septicemia virus is the passaged cell culture RTG-2. Contamination of this cell culture with the virus at a dose of 0.1 TCD50 ensures VHS accumulation on the 2nd-4th day in the titers of lgTCD50/cm3.