Weight and linear parameters of juveniles of coregonids (Coregoninae) grown in conditions of recirculated aquaculture systems

Purpose. Determining the growth dynamics of whitefish juveniles in conditions of recirculated aquaculture systems to current needs of industrial aquaculture of Ukraine. Methodology. The work was performed in accordance with generally accepted guidelines used for coregonid rearing in industrial aquaculture. The study was conducted in a specialized farm for whitefish breeding - "Lavaretus" LLC. Findings. Weight and linear growth during the period of cultivation in controlled conditions of whitefish young-of-the-year were characterized by dynamics, which were generally close to that typical for coregonids. The study included four coregonid species with different feeding types. Planktivorous (peled), bentivorous (whitefish), polyphagous species that is able to feed on various food organisms (muksun) and peled/broad whitefish hybrid. Feeding regime: during the transition to the mixed feeding was carried out 48 times a day (14 hours with an interval of 15 and 30 minutes) manually; further, according to an increase in fish weight was reduced to 4 times a day using automatic feeders. The average weight and length of young-of-the-year grown in a recirculating aquaculture system was: - peled – 5.6 ± 0.4, muksun – 10.1 ± 0.6.9, Baltic whitefish – 8.6 ± 1.2 g, peled/broad whitefish hybrid – 7.9 ± 0.2 g. The coefficient of variability of weights were: peled – 40.4%, muksun – 32.2%, Baltic whitefish – 21.1%, peled/broad whitefish hybrid – 41.9%. Originality. New data on piscicultural-biological parameters and dynamics of growth of juveniles of various coregonids or cultivation in conditions of a recirculating aquaculture system were obtained. Practical value. The development of whitefish farming technology in RAS conditions, which, in contrast to salmon cultivation, is only at the initial stage of implementation, so obtained data will be the basis for the development of whitefish culture in Ukraine.