Reproductive performance and vitellogenin mRNA transcript abundance in the hepatopancreas of female Litopenaeus vannamei fed diets with different soy lecithin content.

A 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. 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). In addition, there was a larger content of long chain polyunsaturated fatty acids (LC-PUFA) in the hepatopancreas of brooding specimens fed with the 20 and 40 SL/kg diets compared to the other treatments. Furthermore, brooding specimens fed with the 40 g SL/kg diet had the greatest hemolymph cholesterol and high density lipoprotein concentrations. The abundance of vitellogenin mRNA transcript was greater in the hepatopancreas of brooding specimens fed with the 40 and 60 g SL/kg diets compared with the other groups. 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.