Content of Fatty Acids in Forage Objects of Juveniles of Salmonids from Rivers of the Lake Onega Basin

Resumo

The forage base of juveniles of salmonids (Atlantic salmon and brown trout) from six rivers of the Lake Onega basin has been analyzed: invertebrate organisms of 23 taxa have been identified. In the macrozoobenthos samples, the content and ratio of fatty acids (FAs) of total lipids are determined. Differences in the ratio of essential 18:3ω-3/18:2ω-6 FAs are found, and the ratio is higher in zoobenthos collected from “salmon” rivers than in those of “brown trout” rivers (within 1.68–2.83 and 0.44–1.08, respectively). The ratio of saturated FAs/polyunsaturated FAs (0.66–0.97 and 0.33–0.59, respectively) in the zoobenthos from salmon rivers is higher than in forage from the brown trout rivers. The content and ratio of physiologically important FAs in the feeding objects of young fish of salmonids have a significant effect on their growth and development.