The effects of lysolecithin on gonadal development and growth performance of giant river prawn, Macrobrachium rosenbergii

This study investigated the effects of lysolecithin (LL) on reproductive performance of Macrobrachium rosenbergii broodstock. Prawns with an average initial weight of 9.96 ± 0.48 g (960 individuals in total) were fed with six isonitrogenous diets formulated with three levels of LL (0 %, 0.2 %, 0.4 %) and two levels of soybean lecithin (SL, 0 % and 2 %), as a 3 × 2 experimental design. These prawns were randomized into 6 groups, with 4 replicates per group (30 females and 10 males in each replicate), for a 56-day trial. The results of two-way ANOVA showed the following：In the 0.2 % LL group, the hormones levels of E2, PROG, and VTG in hemolymph were significantly increased ( P < 0.05). Gonadal vgr , pgrmc 1 and hepatopancreatic ldlr , pkc , plc gene expressions were also significantly upregulated ( P < 0.05). In the 0.4 % LL group, the GSI was significantly higher ( P < 0.05), and oocyte maturity was relatively high. Meanwhile, the expressions of vgr and pgrmc 1 were downregulated with increased maturity, and the expression of hl was upregulated ( P < 0.05). Furthermore, a significant interaction between LL and SL was observed ( P < 0.05). The results of one-way ANOVA showed that: both WG and SGR in the experimental groups were significantly higher than those in the control group. In the LL400 group, the contents of C18:2n6 and total n-6 fatty acids in hepatopancreas were increased, while the content of saturated fatty acids was decreased ( P < 0.05). In summary, 0.2 % LL enhanced lipid uptake, by which vitellogenesis and gonadal development were promoted; 0.4 % LL optimized fatty acid composition in the hepatopancreas, regulated maturity-related genes, and thus gonadal development was facilitated. Furthermore, a synergistic interaction was observed between LL and SL. Gonadal development of M. rosenbergii was promoted by LL via regulating steroidogenesis and lipid metabolism. • Dietary lysolecithin can promote the gonadal development of Macrobrachium rosenbergii . • Dietary LL enhances estrogen levels in Macrobrachium rosenbergii . • Soybean lecithin and LL synergistically upregulate steroidogenic signaling pathway-related genes.