COMPOSITION OF FATTY ACIDS OFTHE TOTAL LIPIDS IN PARR AND SMOLTS OF ATLANTIC SALMON SALMO SALAR L. REARED UNDER DIFFERENT LIGHTING MODESIN AQUACULTURE

Abstract

In the framework of this study, an experiment was carried out on the introduction of constant artificial lighting (24LD) into the standard technology for growing salmon juveniles under conditions of the southern region (Republic of North Ossetia-Alania) and its effect on the composition of fatty acids (FA) of total lipids in muscles and liver parr and smolts of the Atlantic salmon Salmo salar L. It has been established that the FA spectrum of fish is characterized by a change in the key FA factors, indicating the full completion of smoltification and the readiness of smolts for new habitat conditions: a significant increase in the content of polyene FAs (PUFAs) due to (n–3)PUFA, and in them FA of the “marine” type – 22:6(n–3), high values of the ratios (n–3)/(n–6)PUFA, 22:6(n–3)/18:3(n–3).The most significant changes were noticed in the muscles, and for all experimental groups it was found that a decrease in saturated fatty acids (SFA) and an increase in total lipid unsaturation occurs primarily due to PUFAs, while monoene FAs decrease along with SFAs. The data of experimental studies of the lipid and fatty acid composition of salmon youngs, as well as a higher proportion of smolts in the studied groups of fish, indicate that the most successful process of smoltification restructuring occurred in groups with constant lighting and 24 hours feeding and a natural regime of lighting and feeding.