Amin Oujifard

30-day nutritional study was conducted for determining the effects of supplementing soy lecithin (SL) in the diet of female Litopenaeus vannamei. Four isonitrogenous and isoenergetic diets were supplemented with graded amounts of SL including 0 (control), 20, 40 and 60 g Kg?1. The brooding specimens fed the 40 g SL/kg diet had the greatest gonadosomatic index (3.4 ± 0.2 %) and the shortest latency period from eyestalk ablation to the first spawning (5 days).Results indicate that supplementing diets with 40 g SL/kg can improve growth and reproductive performance in L. vannamei female brooding specimens probably by enhancing LC-PUFA deposition and enhancing vitellogenin gene expression, as indicated by a greater abundance of mRNA transcript for vitellogenin, in the hepatopancreas