Известия ТИНРО (Dec 2017)
Comparative evaluation of starting traditional and fermented mixed fodders for juveniles of pacific salmon
Abstract
Needs for artificial food for salmons considerably increase recently because of foundation of new salmon hatcheries and reconstruction of existing hatcheries in Sakhalin, Kamchatka, Primorye, and Khabarovsk and Magadan regions. In conditions of shortage of Russian-made mixed fodders of high quality and urges toward substitution of imported fodders by domestic ones, highly productive fodders for salmons should be developed using modern scientific knowledge and industrial technologies. Fermented pastas on the base of raw pollock and wastes of other fish processing (chum salmon, saury, herring) are presented as components of mixed fodders for juvenile salmons corresponding by their quality and safety to nutritional requirements of juveniles. Recipes of starting fodders for farming of salmons are proposed with 6 % and 10 % of dry fermentolyzate of these raw materials. These experimental fodders are successfully tested in conditions of salmon hatcheries. The mixed fodder B-1-6 % has lower content of protein (38.5 %) but higher content of lipids (14.5 %) and carbohydrates (37.5 %), as compared with the B-1-10 %, its amino acid composition corresponds to the needs of chum salmon. In the experiments, the feeding coefficients of the experimental fodders (0.64-0.86) were better than those of the fodders Aller Aqua (Denmark) and Dalkorm (Russia) with feeding coefficients 1.00 and 1.44, respectively. The fodders Aller Aqua and Dalkorm caused some pathomorphological changes in digestive system of juvenile chum salmon that reduced quality of juveniles and impeded their growth; the experimental fodder with 6 % of dry fermentolyzate caused mild lipoidal degeneration of liver in reversible form for 15 % of the examined juveniles, but this pathology had no significant effect on quality of the released juveniles. Introduction of high-protein dry fermentolyzate to mixed fodders allows to reduce the portion of fish flour without reducing quality of their protein component, herewith the juveniles vitality increasing.
Keywords
