Effects of dietary lipids on growth, fatty acid composition, and lipid metabolism of the green sea urchin Strongylocentrotus droebachiensis

The effects of different dietary lipids (hydrogenated coconut oil, corn oil, linseed oil, and mixtures of corn oil, linseed oil, menhaden oil and/or soy lecithin) on growth and fatty acid composition of the sea urchin Strongylocentrotus droebachiensis were investigated. The highest biomass gain expressed as relative growth rate (%g/day) was found when sea urchins were fed a diet containing corn oil, linseed oil, menhaden oil, and lecithin (CLnML) However the RGR of urchins fed CLnML was not significantly different from urchins fed corn (C), corn and linseed (CLn), and corn, linseed and menhaden (CLnM) (p ≥ 0.05). The poorest growth was obtained with an EFA deficient control diet with hydrogenated coconut oil (HCO) as the dietary lipid source. The addition of soy lecithin to the diet (CLnML) enhanced the production and incorporation of 20:4n-6 in the test and gonad. The enzymatic capabilities of sea urchins for desaturation and elongation of 18:2n-6 to 20:4n-6, and 18:3n-3 to 20:5n-3, as well NMID synthesis were determined. (Abstract shortened by UMI.)...