title: Influence of the marine feeding area on the muscle and egg fatty-acid composition of Atlantic salmon Salmo salar spawners estimated from the scale stable isotopes.
abstract: Fatty acids in muscle tissue and eggs of female Atlantic salmon Salmo salar spawners were analysed to evaluate the dietary quality of their final feeding areas in the Baltic Sea. The final likely feeding area was identified by comparing stable carbon and nitrogen isotope composition of the outermost growth region (final annulus) of scales of returned S. salar with that of reference S. salar caught from different feeding areas. Some overlap of stable-isotope reference values among the three areas, in addition to prespawning fasting, decreased the ability of muscle tri-acylglycerols to discriminate the final likely feeding area and the area's dietary quality. Among three long-chained polyunsaturated fatty acids, docosahexaenoic acid (DHA; 22:6n-3), eicosapentaenoic acid (EPA; 20:5n-3) and arachidonic acid (ARA; 20:4n-6), the proportions of ARA in total lipids of spawning S. salar muscle and eggs showed a significant negative correlation with increasing probability of S. salar having returned from the Baltic Sea main basin (i.e. the Baltic Sea proper). The results suggest that ARA in muscle and eggs is the best dietary indicator for dietary characteristics of final marine feeding area dietary characteristics among S. salar in the Baltic Sea.
authors.affiliation: University of Jyvaskyla, Department of Biological and Environmental Science, P. O. Box 35, FI-40014, Jyvaskyla, Finland.|University of Jyvaskyla, Natural History Museum, P. O. Box 35, FI-40014, Jyvaskyla, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Torniainen
authors.affiliation: WasserCluster - Biologische Station Lunz, A-3293, Lunz am See, Austria.
authors.forename: M J
authors.initials: MJ
authors.lastname: Kainz
authors.affiliation: University of Jyvaskyla, Department of Biological and Environmental Science, P. O. Box 35, FI-40014, Jyvaskyla, Finland.
authors.forename: R I
authors.initials: RI
authors.lastname: Jones
authors.affiliation: Natural Resources Institute Finland (Luke), P. O. Box 2, FI-00791, Helsinki, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Keinänen
authors.affiliation: Natural Resources Institute Finland (Luke), P. O. Box 2, FI-00791, Helsinki, Finland.
authors.forename: P J
authors.initials: PJ
authors.lastname: Vuorinen
authors.affiliation: University of Jyvaskyla, Department of Biological and Environmental Science, P. O. Box 35, FI-40014, Jyvaskyla, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Kiljunen
mesh_terms: D063147:Animal Distribution; D000818:Animals; D004032:Diet; D005227:Fatty Acids / Q000737:chemistry* / Q000378:metabolism; D005260:Female; D009584:Nitrogen / Q000737:chemistry*; D009587:Nitrogen Isotopes; D010063:Ovum / Q000737:chemistry* / Q000378:metabolism; D020317:Salmo salar / Q000502:physiology*
chemical_list: D005227:Fatty Acids; D009587:Nitrogen Isotopes; D009584:Nitrogen
keywords: Baltic Sea; M74 syndrome; fasting; lipids; thin layer chromatography