Effect of stoking density on the productivity parameters of young-of-the-year tench (Tinca tinca Linnaeus, 1758) grown in recirculation aquaculture system conditions

Purpose. To characterize the productive and biological features of juvenile tench [Tinca tinca Linnaeus, 1758] grown in a recirculation aquaculture system and to select the optimal stocking density for intensive cultivation technology. Methodology. The studuy was conducted at the incubation workshop of “Karpatskyi Vodogray” LLC using a recirculation aquaculture system. Two 0.96 m3 tanks were used for the study.The material for thestudy were tench juveniles obtained in hatchery conditions. The cultivation of young-of-the-year was carried out in two stages: cultivation for 28 days at stocking densities of 100 and 75 thousand ind./m3, with the repeatability for two years [Experiment I – 2021, Experiment II – 2022]. Over the next 94 days, at stocking densities of 15 and 20 thousand ind./m3 [Experiment I – 2021] and 10 and 15 thousand ind./m3 [Experiment II – 2022]. The data obtained as a result of the experiments was subjected to statistical processing in MS Excel 2016. The criteria for analyzing were their average value and standard error [M±m]. Findings. The study showed that when growing young-of-the-years in a recirculation aquaculture system, the most optimal stocking density at the first stage of cultivation was 100 thousand ind./m3.Reducing the stocking density to 75 thousand ind./m3 allowed increasing the survival rate of larvae by 2.0–2.5%, however, there was no clear effect on their growth rate. At the second stage, at a stocking density of tench juveniles of 10–20 thousand ind./m3 similar productive and biological parameters of young-of-the-years were obtained, while their yield yield yield yield