Paper
Dietary effects on the fatty acid signature of whole Atlantic cod (Gadus morhua)
Published Jun 1, 1998 · Penny E. Kirsch, S. Iverson, W. Bowen
Canadian Journal of Fisheries and Aquatic Sciences
158
Citations
8
Influential Citations
Abstract
Understanding the influence of dietary fatty acids on whole fish is necessary to evaluate the degree to which fatty acids may be used for understanding foraging patterns in fish, as well as in marine mammals that consume their prey whole. Adult Atlantic cod (Gadus morhua) were fed two prey items that differed significantly in fat content and fatty acid compositions. Cod were first fed squid (Illex illecebrosus, 2.0% fat) for 6 weeks, followed by Atlantic mackerel (Scomber scombrus, 15.7% fat) for 8 weeks. Twenty whole cod were individually analyzed at each of 0, 3, 6, 11, and 14 weeks. Despite being on a low-fat squid diet, in only 3 weeks, cod fatty acid patterns changed significantly to reflect the patterns found in squid and did not further change at 6 weeks. When switched to a high-fat mackerel diet, total body fat of cod increased and the fatty acid composition of cod changed significantly in the direction of patterns found in mackerel. Despite changes in cod fatty acid signatures, cod were readily distinguished from the fatty acid signatures of their diets. Our results provide support for the use of fatty acids as indicators of diet at upper trophic levels. Resume : On doit connaOtre liinfluence des acides gras alimentaires sur le poisson entier pour Otablir dans quelle mesure les acides gras peuvent Œtre utilisOs pour comprendre les comportements de recherche de nourriture des poissons et des mammifres marins qui consomment leurs proies entires. On a nourri des morues ( Gadus morhua) adultes avec deux types de proie dont les teneurs en gras et les compositions en acides gras diffOraient significativement. Les morues ont diabord consommO du calmar (Illex illecebrosus, 2,0 % de matires grasses) durant 6 semaines, puis du maquereau ( Scomber scombrus, 15,7 % de matires grasses) durant 8 semaines. Vingt morues entires ont OtO individuellement analysOes ‡ chacune des Otapes suivantes : 0, 3, 6, 11 et 14 semaines. Bien que les morues aient OtO exposOes ‡ un rOgime de calmar faible en matires grasses, en seulement 3 semaines, les profils diacides gras des morues ont changO significativement pour reflOter ceux du calmar, et ils Otaient les mŒmes ‡ 6 semaines qui‡ 3 semaines. Quand les morues sont passOes au rOgime de maquereau riche en matires grasses, leur teneur corporelle totale en matires grasses siest accrue et leur composition en acides gras a changO significativement pour siapprocher de celle du maquereau. MalgrO les changements dans les profils diacides gras de la morue, ces derniers demeuraient nettement distincts des profils diacides gras de ses proies. Nos rOsultats indiquent quiil est possible diutiliser les acides gras comme indicateurs du rOgime alimentaire dans les niveaux trophiques supOrieurs. (Traduit par la ROdaction)
Highly CitedCod fatty acid patterns can be used to understand foraging patterns in fish and marine mammals that consume their prey whole, as they can change significantly in response to diet changes.
Full text analysis coming soon...