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This thesis deals with an issue of Zander (Sander lucioperca) production in a recirculating aquaculture system RAS in different oxygen rates (50-80% O-, 80-110% Os and O+ 110-150%). Zander weighted W=22,98?15g was planted into two identical recirculating systems with different water temperature. SGR, FCR and FC of survival and general health condition of kept fish in hematology, biochemistry as well as stress indicators were evaluated. The results proved a negative influence of hypoxia (50-80%) on the food reception, growth and general survival of experimental fish kept in this environment in both the recirculating systems with water temperature 20 and 23°C. In the group O- kept in RAS 20°C, higher coefficient of FCR=1,11 was proved in comparison with group O (normoxia) and group O+ (hyperoxia), where no significant difference (p0,05) was recorded. The health condition showed a significant difference (p0,05) of O group in comparison with group O+ and O in RAS 20°C during the TBARS evaluation (brain, gills, muscle), assessing SOD in liver, and GPx (brain and muscle). By determining the HSI, SSI and VSI indexes, the significant differences (p0,05) of HSI and VSI for O+ and O groups in comparison with O- were proved. |
