Application of Products of Hydrolysis of Sprait Waste in Feeding the European White in Aquaculture

Abstract

European whitefish are widely used for artificial reproduction in aquaculture. Relevant is the search for alternative solutions for protein supplements in the composition of animal feed for its cultivation. A promising source of valu-able protein is fish waste from canning industries. In the Kaliningrad region, 80% of Russian canned food "Sprats in oil" is produced. The daily amount of sprat waste is 2-10 tons. The use of protein products of hydrolysis of smoked sprat heads instead of a part of fishmeal in compound feeds for whitefish juveniles was studied in this work. Hy-drolysis was carried out by a high-temperature method in an aqueous medium to obtain two types of protein sup-plements. In the first experiments, a 5% low molecular weight peptide supplement with a protein content of 82.7% was introduced into the model feed instead of the corresponding amount of fishmeal. In the second series of exper-iments, a 10% protein-mineral supplement was introduced with a protein content of 54.5% and mineral substances of 24.0%. The experiments were carried out in a closed aquaculture system based on AtlantNIRO. After 56 days of feeding, the fish breeding, morphobiological and organosomatic parameters of the fish were comparatively studied. . The promising potential of additives as feed components has been established. The introduction of a 5% peptide additive led to an increase in the fry survival rate. The use of a 10% protein-mineral supplement resulted in higher growth rates and lower feed ratios. In both experiments, there was no negative effect on the growth and morpho-physiology of the studied fish. For more reliable results, further study of alternative amounts of inclusion of these additives in the feed is required.