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The relevance of studying the biopotential of shrimp waste and their hydrolysates is due to the need for complex processing of secondary raw materials of aquatic organisms to obtain useful products. At the fish processing plant Vichyunai-Rus LLC when manufacturing food products from white-legged shrimp, up to 60 % of the mass of waste (cephalothorax, shell) remains. This raw material contains valuable organic components, but is not processed. The paper proposes its complex processing with the production of hydrolysates in two ways – high-temperature and enzymatic. During thermohydrolysis in the aquatic environment, three fractions are formed from shrimp waste (fatty, water-soluble and water-insoluble). After separation, the water-soluble fraction was sublimated, and the water-insoluble fraction was dried by convection. The fat fraction was further purified by washing in warm water. The general chemical composition of shrimp waste and hydrolysis products has been studied. It has been shown that water-soluble hydrolysates are a good source of protein components (66.6–71.6 %). In comparative studies of the amino acid composition of water-soluble hydrolysates, the presence of all essential amino acids is established with minor differences between the samples. Both hydrolysates are dominated by alanine, arginine, glycine, isoleucine, lysine, aspartic acid, tyrosine, valine (3.3–6.4 g/100 g of protein). In terms of formol-titratable nitrogen in fermentolisates, alkalase ferments shrimp waste more actively than collagenase. The fatty acid composition of lipids isolated by thermohydrolysis from shrimp waste has been analyzed. Shrimp oil is characterized by a high content of polyunsaturated fatty acids (44.7 %) with a relatively low content of omega-3 family acids (10.7 %) and a high content of omega-6 (33.9 %) at a ratio of 1 : 3.2 (close to the physiologically recommended). The organoleptic characteristics of water-soluble and water-insoluble shrimp hydrolysates have been studied. Due to the content of valuable biologically active components in hydrolyzates, their use as food and feed additives – sources of active peptides, high-molecular proteins, minerals and chitinous components – is recommended.

The averaged indicators of the weight growth of four generations of trout at different temperatures in the time interval of the life cycle from the transfer of larvae to cultivation until the fish reaches a portioned commercial weight of 400 g when the first withdrawal of products for sale takes place have been analyzed. It has been shown that fish of different generations passes into the weight category "goods" sequentially, but after reaching different ages, while there is no direct correlation between the terms "generation formation" – "first withdrawal for sale". According to our data the most intensive weight growth of fish has been noted in the temperature range equal to 8–13 °C. An increase in the water temperature in the cages to 15–18 °C has led to a slowdown, and then to the suspension of the accumulation of fish biomass. In cages operating in the area of Kola NPP heated water trout of April generation gains the commercial weight of 400 g in 7–8 months after landing of larvae for cultivation, November trout – after 15 months. Trout of October and January generation reaches commercial weight at 11 and 9 months, respectively. The stretching of timing of biomass accumulation is most pronounced in the autumn generation of trout. It has been found that the greatest increase in weight per unit body (145.1 mg per day) is provided by the trout of the January biological group, the smallest – by the November trout (75.8 mg per day). The energy reserve of heat allowing for differently derived individuals to reach a commodity weight of 400 g, is in the range from 3 320 to 5 300 degree-day.

The study presents the development of a biosafety system in aquaculture activities on the territory of the Murmansk region, accounting for the existing scientific developments and recommendations. The authors’ scientific and practical experience in cultivating the hydrobionts in the conditions of the Polar region is the core of the study. The materials for the development of the regional biosafety program of salmon cages farms were the longstanding epizootic and ichthiopathological studies of the department of fish physiology and diseases, aquaculture objects of the Murmansk Regional Animal Disease Control Center (2013–2019). The most significant risks for salmon net farms of the Murmansk region are: carrying out activities in the zone of risky fish farming; lack (or scarcity) of high-quality nursery material of domestic origin, absence of the center for research and prevention of fish diseases; the absence of the specialized enterprise for aquaculture waste disposal. The developed system of practical safety of aquaculture enterprises in the region will allow managing the risks through certain efforts and events. The principles of biosafety system development in accordance with the environmental requirements and associated conditions for maintaining the epizootic and ichthyopathological safety in the commercial cultivation of fish are considered. Preventive measures to maintain epizootic safety in fish farms have been developed. Suggestions and recommendations are formulated to conduct safe aquaculture activities in the conditions of the Murmansk region. A integrated approach to biosafety through certain risk management activities is aimed at solving the problems of preserving the health of cultivated objects resulting in the maximal feasibility of the enterprise and maintaining the biodiversity of natural communities and environmental sustainability in the region.