Compositions of fatty acids in the lipids of chum salmon during spawning migration.

Abstract

The fatty acid compositions of total lipids from various tissues of chum salmon caught on the coast and upstream at the spawning site have been investigated in detail with open-tubular gasliquid chromatography. At least 100 components were detected by GLC, of which 53 components were identified. Furan fatty acids could be detected in other tissues except for the flesh.In the skin, flesh and gonad, lipid contents and fatty acid contents decreased during the migration from seawater to freshwater. The distributions of positional isomers within 20:1 and 22:1 changed in this period. Although lipid contents and fatty acid contents in the liver and viscera almost maintained at constant levels, the fatty acid compositions changed during the migration. Especially, the contents of C20 and C22 monounsaturated fatty acids increased in this period. There were sex differences of fatty acid compositions in other tissues except for the liver of chum salmon caught on the upstream.