LAUSR

Abstract An 8-week feeding trial with black seabream, Acanthopagrus schlegelii, was conducted to evaluate effects of dietary n-3 LC-PUFA/n-6 C18 PUFA (LC-PUFA, long-chain polyunsaturated fatty acid; C18 PUFA, PUFA with 18 atoms of carbon) ratio on growth, feed utilization, fatty acid composition and lipid related gene expression. Five isoproteic and isolipidic diets were formulated to contain different n-3 LC-PUFA/n-6 C18 PUFA ratios: 0.1, 0.4, 0.5, 0.8, 1.0. Each diet was assigned randomly to feed triplicate net cage of 90 fish (30 fish per net cage) of initial weight 3.0 ± 0.0 g. As a result, final weight (FW), weight gain (WG), specific growth rate (SGR), feed efficiency (FE) and protein efficiency ratio (PER) were all significantly affected by dietary n-3 LC-PUFA/n-6 C18 PUFA ratio (P   0.05). Likewise,The moisture contents, crude protein, crude lipid and ash contents in the whole body and muscle were all not affected by experimental diets (P > 0.05). Tissue fatty acid profiles reflected the diets. The highest concentration of triacylglycerol (TG) was observed in fish fed the lowest ratio (0.1) (P