Fatty Acid Profile of Sunshine Bass: I. Profile Change is Affected by Initial Composition and Differs Among Tissues

Abstract

Fatty acid (FA) composition of fillet tissue can be tailored by transitioning fish from alternative lipidbased, low long-chain polyunsaturated fatty acid (LCPUFA) grow-out feeds to high LC-PUFA ‘‘finishing’’ feeds. To address whether grow-out feed composition influences the responsiveness of fillet tissue to finishing, sunshine bass (SB, Morone chrysops 9 M. saxatilis) were reared to a submarketable size on grow-out feeds containing fish oil (FO) or a 50:50 blend of FO and coconut (CO), grapeseed (GO), linseed (LO), or poultry (PO) oil. For the final 8 weeks of the trial, fish were either maintained on assigned grow-out feeds or finished with the 100% FO feed. Production performance was unaffected by dietary lipid source, but fillet FA profile generally conformed to nutritional history. Regardless of grow-out regimen, finishing had a significant restorative effect on fillet FA composition; however, complete restoration of control levels of 20:5n-3, 22:6n-3, total LC-PUFA and n- 3:n-6 FA ratio was achieved only among fish fed the CObased grow-out feed. Saturated fatty acids (SFA) appear to be preferential catabolic substrates, whereas medium-chain and long-chain PUFA are selectively deposited in tissues. Provision of SFA in grow-out feeds appears to optimize selective FA metabolism and restoration of beneficial fillet FA profile during finishing.

Description

Keywords

Fish oil, Alternative lipid, Finishing feed, Fatty acid turnover/dilution, LC-PUFA, Morone spp.

Citation

Lipids (2008) 43:629–641

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