Abstract:The jumbo squid (Dosidicus gigas) is a pelagic cephalopod endemic to the eastern Pacific Ocean with a valuable commercial role. In this study, fatty acid profiles were identified in jumbo squid muscle tissues from three harvest locations. Comparative analysis was used to evaluate spatial variation in fatty acid profiles of different geographic origins. Results showed significant differences in fatty acid profiles among squid muscle tissues from different sampling locations. The number of fatty acid types from the squid off Peru (28) was high compared with that from squid in the waters of the equatorial central eastern Pacific (27) and those off Chile (24). Nonetheless, among all three geographic origins, the dominant fatty acids were polyunsaturated fatty acids (PUFA), which accounted for 59.68%~69.28% of the total amount of all fatty acids, followed by saturated fatty acids (SFA, 20.71%~27.28%) and monounsaturated fatty acids (MUFA, 10.01%~13.04%). C16:0, C18:0, C20:1n9, C18:2n6, C20:5n3 (eicosapentaenoic acid, EPA), and C22:6n3 (docosahexaenoic acid, DHA) were the primary fatty acids in jumbo squid muscle tissues, which accounted for more than 81% among all areas. The results of analysis of similarity (ANOSIM) and similarities of variance (SIMPER) showed that the spatial heterogeneity of fatty acid profiles was mainly influenced by C16:0, C18:2n6, C20:4n6, and DHA. We propose that the observed variations could be the result of differences in oceanographic conditions, food sources, and energy demands of squid among varied regions. Overall, these results demonstrated the feasibility of using fatty acid analysis to study the feeding ecology of jumbo squid. Novel information on the heterogeneity of fatty acid profiles among harvest locations may have important implications for their nutrition studies and for better utilizing this important resource.
