Fatty acid profile of sunshine bass: I. Profile change is affected by initial composition and differs among tissues.
Fatty acid (FA) composition of fillet tissue can be tailored by transitioning fish from alternative lipid-based, low long-chain polyunsaturated fatty acid (LC-PUFA) 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 x 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 CO-based 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.
Department of Zoology, Southern Illinois University Carbondale, Carbondale, IL 62901-6511, USA. saluski@siu.edu
Jesse T
JT
Trushenski
Heidi A
HA
Lewis
Christopher C
CC
Kohler
D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D001492:Bass; D004032:Diet; D005227:Fatty Acids / Q000032:analysis*; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage / Q000032:analysis; D005398:Fisheries; D018482:Muscle, Skeletal / Q000737:chemistry*
D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated