Fatty acid signatures in seabird plasma are a complex function of diet composition: a captive feeding trial with herring gulls

Käkelä, R., Furness, R.W., Kahle, S., Becker, P. H. and Käkelä, A. (2009) Fatty acid signatures in seabird plasma are a complex function of diet composition: a captive feeding trial with herring gulls. Functional Ecology, 23(1), pp. 141-149. (doi: 10.1111/j.1365-2435.2008.01475.x)

Abstract

Tissue fatty acid signatures (FAS) can complement traditional methods of studying seabird diets. Although plasma lipid FAS are known to indicate dietary changes qualitatively, here we test whether they can be used to determine the proportions of different dietary items in a quantitative manner.2. Captive herring gulls (Larus argentatus) were fed North Atlantic plaice Pleuronectes platessa (demersal species made available to wild seabirds by fisheries) and herring Clupea harengus (pelagic fish often found naturally in their diet) with different mixing ratios (0%, 10%, 20% and 50% herring).3. Major fatty acids did not indicate diet, but several minor components in plasma, for example, 14 : 0, 18 : 3n-3, 18 : 4n-3 and C20-22 monounsaturated fatty acids (MUFA), showed good correlations with diet composition. Different fatty acids were incorporated from diet into plasma lipids with different calibration coefficients.4. Together with dose-dependent but inefficient (low calibration coefficient) transfer of 22 : 1n-11 (a major fatty acid of herring) to the plasma FAS of the gulls, the percentages of potential chain shortening products of 22 : 1n-11, that is, 20 : 1n-11, 18 : 1n-11 and 16 : 1n-11 increased with increasing proportion of herring in the diet. Notably, the dietary supply of these fatty acids itself did not change. Thus the metabolic products of certain dietary fatty acids can reflect the amount of their dietary precursors in a quantitative way.5. Despite the fact that many major fatty acids in FAS of seabird plasma are greatly modified by endogenous metabolism, several minor components of FAS (in this experiment 14 : 0, branched chain 17 : 0, 18 : 1n-7, 18 : 3n-3, 18 : 4n-3, C20-22 MUFA with their chain shortening products, and 22 : 4n-6) that can be accurately and reliably quantified by gas chromatography, vary proportionally to diet composition, allowing their use for monitoring temporal and spatial differences in seabird

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Furness, Professor Robert
• Authors: Käkelä, R., Furness, R.W., Kahle, S., Becker, P. H., and Käkelä, A.
• Subjects: Q Science > QL Zoology
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Functional Ecology
• Publisher: Blackwell
• ISSN: 0269-8463
• ISSN (Online): 1365-2435
• Published Online: 03 September 2008