Comparative Characteristics of the Fatty-Acid Composition of Lipids in Factory and Wild Juveniles of Atlantic Salmon Salmo salar L.

Differences between factory and wild juvenile salmons (fingerlings at the 0+ age and 1+ parrs) in the content of physiologically significant fatty acids and their ratios are shown. Factory juveniles (age 0+ and 1+) have a very low content of physiologically significant 18:3n-3 and 20:4n-6 fatty acids when compared with wild individuals, whereas relatively high amounts of 22:6n-3 (age 0+) and 18:2n-6 fatty acids (age 1+) were noted. Simultaneously, the factory juveniles (age 0+ and 1+) differ from wild juveniles in a lower ratio of 18:3n-3/18:2n-6 essential fatty acids (by 7.9 and 6.4 times, respectively). The ratio of total polyunsaturated n-3/n-6 fatty acids is reliably equal in wild and factory fingerlings (age 0+), whereas it is 2 times lower in parrs than in factory fish. A relatively high content of oleic 18:1n-9 fatty acid and minor 20:1n-9, 22:1n-11 fatty acids are found in the factory juveniles, but the level of saturated fatty acids decreases due to 16:0 and 18:0. The high metabolic rate of fatty-acid metabolism in wild juveniles is evidenced by a higher ratio of 16:0/18:1n-9 compared to that in the factory fish (1.50 and 1.47 vs 0.84 and 0.46 for fingerlings (age 0+) and parrs (age 1+), respectively). The lower metabolic rate of fatty acid metabolism in factory juveniles, especially for parrs (age 1+), is accompanied by a high accumulation of their body mass (in fourfold) when compared with wild individuals of the same age.