Currently, the regulational effect of arginine on the energy metabolism is unknown in broodstock shrimp nutrition. Accordingly, an eight-week feeding trial was conducted to confirm it in female Litopenaeus vannamei. Six diets were formulated to contain graded levels of arginine (2.90 %, 3.58 %, 4.08 %, 4.53 %, 5.04 % and 5.55 %). A total of 540 shrimp (with an initial weight of approximately 14 g) were allocated at random to six treatments, each of which consisted of three tanks with 30 shrimp each. The results showed that with the rise in the level of dietary arginine supplementation, growth performance showed an increasing trend, reaching the highest value in the 5.55 % arginine group. The gene expression of cellular energy sensor AMP-activated protein kinase was up-regulated in muscle and hepatopancreas. Dietary arginine supplementation decreased hemolymph glucose content and hepatopancreas crude lipid content, increased muscle crude lipid content, glycogen content in muscle and hepatopancreas. Dietary arginine increased muscle crude protein content, decreased hepatopancreas crude protein content and activated the target of rapamycin 1 pathway. Above results were further confirmed by gene expression. In addition, shrimp were injected with dsGFP and dsNOS for 48 h and successfully constructed the RNA interference model. The findings showed that the levels of nos, cgmp, ampk (a, b, c), genes involved in glucose metabolism, lipid metabolism and amino acid metabolism were inhibited. In the conclusion, arginine supplementation could promote growth performance through modulating energy metabolism. Arginine–NO pathway modulated energy metabolism in hepatopancreas and muscle to promote tissue glycogen synthesis, muscle protein and lipid deposition in female L. vannamei.
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