Open AccessDummy regression analysis for modelling the nutritionally tailored fillet fatty acid composition of turbot and sole using gilthead sea bream as a reference subgroup category
Author(s) -
BallesterLozano G.F.,
BeneditoPalos L.,
Riaza A.,
Navarro J.C.,
Rosel J.,
PérezSánchez J.
Publication year - 2014
Publication title -
aquaculture nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.941
H-Index - 79
eISSN - 1365-2095
pISSN - 1353-5773
DOI - 10.1111/anu.12095
Subject(s) - turbot , fillet (mechanics) , polyunsaturated fatty acid , biology , food science , fatty acid , fish oil , linear regression , analysis of variance , zoology , rapeseed , fishery , statistics , biochemistry , fish <actinopterygii> , mathematics , materials science , composite material
Abstract Farmed turbot and sole were sampled at different stages of the production cycle for analysis of fillet lipid content and fatty acid ( FA ) composition. The entire data set along with our own published data on gilthead sea bream were fitted to dummy regression equations with turbot and sole as dummy variables, gilthead sea bream as a reference subgroup category, and diet FA composition and fillet lipid content as independent variables. The relative contribution of each independent variable to the total variance was found to vary within and among FA s and fish species, but strong correlation coefficients (0.76 < r 2 > 0.99) were found for almost all of the FA equations, including saturated FA s, monoenes and long‐chain polyunsaturated fatty acids ( PUFA ) of n‐3 and n‐6 series. Given the differences in lipogenic activities of the fish species, major interaction effects between fillet lipid content and dummy variables were found for monoenes and saturated FA s. The proposed equations (hosted at www.nutrigroup-iats.org/aquafat ) were able to fit different proportions of EPA , DPA and DHA underlying the fish species differences in FA desaturation/elongation pathways. The robustness of the model was proven with extra data from the three fish species, allowing a close linear association near to equality for the scatter plot of observed and predicted values.