title: Stable isotope variability in tissues of the Eurasian perch Perca fluviatilis.
abstract: Stable isotope analysis is frequently used as a complementary method of dietary analysis, to describe trophic relationships and assess food-web structure. These studies allow a precise determination, based on the calculation of a diet-tissue fractionation factor. The fractionation factor, determined for whole organisms or specific tissues, may vary substantially in natura. In the present study, delta13C and delta15N were assessed in lipid-free tissues (spleen, liver, viscera, scales, gills, spine, white muscle, brain) and in available energy reserves (proteins, glycogen, lipids) of Eurasian perch (Perca fluviatilis) reared under controlled conditions and fed for 4 months with the same artificial diet. Some discrepancies in delta15N and delta13C data were observed among tissues, respectively up to 3.43 per thousand and 2.54 per thousand for delta15N and delta13C. The 15N signature in organs depends on their metabolic activity. Despite a significant delta13C enrichment from feed to tissues, the lipids in spine, liver and viscera exhibit a certain stability.
authors: Univ Paris-Sud, Laboratoire Ecologie Systématique et Evolution, UMR8079, Orsay, France.
authors: Yan
authors: Y
authors: Vollaire
authors: Damien
authors: D
authors: Banas
authors: Marielle
authors: M
authors: Thomas
authors: Hélène
authors: H
authors: Roche
mesh_terms: D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001923:Brain Chemistry; D002247:Carbon Isotopes; D004734:Energy Metabolism; D005880:Gills / Q000737:chemistry; D006003:Glycogen / Q000032:analysis; D008055:Lipids / Q000032:analysis; D008099:Liver / Q000737:chemistry; D018656:Muscle Fibers, Fast-Twitch / Q000737:chemistry; D009587:Nitrogen Isotopes; D010471:Perches / Q000378:metabolism*; D011506:Proteins / Q000032:analysis; D013131:Spine / Q000737:chemistry; D013154:Spleen / Q000737:chemistry; D014781:Viscera / Q000737:chemistry
chemical_list: D002247:Carbon Isotopes; D008055:Lipids; D009587:Nitrogen Isotopes; D011506:Proteins; D006003:Glycogen