Kolářová Jitka author Křišťan Jiří author Malinovskyi Oleksandr author Velíšek Josef author Stará Alžběta author Rahimnejad Samad author Policar Tomáš author text journal article 2021 The aim of this study was to examine the effects of ozonation on the water quality, and growth, blood biochemistry, antioxidant capacity and survival of pikeperch (Sander lucioperca) reared in a recirculation aquaculture system for 30 weeks. A group without ozone treatment was used as a control. The ozone application led to a significant reduction of the water chemical oxygen demand, biological oxygen demand and unsuspended solids concentration. The results revealed that an ozone treatment as a water treatment method has a positive influence on the intensive culture of pikeperch ensuring a higher survival rate (77%) compared to the non-treated control group (67.2%). Moreover, the ozonation prevented fin damage to a large extent and reduced the prevalence of an Ichthyophthirius multifiliis infection. Furthermore, the ozone application led to a reduction in the thiobarbituric acid reactive substance level and enhanced the superoxide dismutase activity in the fish gills. However, the effect of ozonation was null on the plasma biochemical parameters. Overall, these findings suggest that an ozone treatment, using adequate technological equipment to destroy the residual ozone, improves the water quality and protects pikeperch against any possible infection and fin damage in a recirculation aquaculture system. blood biochemistry; oxidative stress; survival; body condition; health condition 10.17221/54/2021-CJAS https://cjas.agriculturejournals.cz/artkey/cjs-202109-0005.php https://cjas.agriculturejournals.cz/artkey/cjs-202109-0005.php continuing 66 9 381 390 2021 12121819 periodical academic journal