Dietary effects on the fatty acid signature of whole Atlantic cod (Gadus morhua). Canadian Journal of Fisheries and Aquatic Sciences 55

• Main Authors: Penny E. Kirsch, Sara J. Iverson, W. Don Bowen, Stephen R. Kerr, Robert G. Ackman
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 1998
• Subjects: atlantic cod; Gadus morhua
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.508.3851; http://bowenlab.biology.dal.ca/data/KirschFACodCJFAS1998.pdf

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. Résumé: On doit connaître linfluence des acides gras alimentaires sur le poisson entier pour Øtablir dans quelle mesure les acides gras peuvent Œtre utilisØs pour comprendre les comportements de recherche de nourriture des poissons et des mammifŁres marins qui consomment leurs proies entiŁres. On a nourri des morues (Gadus morhua) adultes avec deux types de proie dont les teneurs en gras et les compositions en acides gras diffØraient significativement. Les morues ont dabord consommØ du calmar (Illex illecebrosus, 2,0 % de matiŁres grasses) durant 6 semaines, puis du maquereau (Scomber