Effects of dietary flavone on growth performance and Omics profiles of Litopenaeus vannamei under high-temperature

This 60-day culture trial was conducted to investigate the effects of flavone on the growth performance and intestinal microbiota of Litopenaeus vannamei at high temperatures utilizing transcriptomics and metabolomics analysis. A total of 240 healthy shrimp (Average weight 2.62 ± 0.06 g) were administered diets containing four different levels of flavone: 0 g/kg (control), 5 g/kg (FLV1), 10 g/kg (FLV2) and 15 g/kg (FLV3). Intestine and hepatopancreas tissues from the control and treatment groups were analyzed for changes in microbiota, transcriptome and metabolome. Shrimps fed with an experimental diet exhibited a significant increase in growth performance indices compared to the control group. The most efficient feed conversion ratio (FCR) was recorded in the FLV2 group compared to other groups, proving the efficacy of flavone as an additive. Specifically, the thermal tolerance test revealed an increase in the survival rates of shrimps fed an enriched diet compared to the control group. The result also showed that the survival rate decreased as the temperature reached 40 °C. The intestinal microbiome composition showed a significant increase in the abundance of Firmicutes and Actinobacteria . The transcriptomic analysis highlighted the up-regulation of Glutathione S-transferase and pancreatic lipase-related protein , while the macrophage mannose receptor and Maltase-glucoamylase expression was down-regulated. Metabolomic analysis identified 4 393 significantly differing metabolites, of which 966 were upregulated and 1 279 downregulated. The integrated transcriptomic and metabolomic analysis identified upregulated genes ( gk, ar, dgk, gpat3, agpat-1, gplat1, pnpla2, and plrp2 ) in the glycerolipid metabolism pathway responsible for lipid metabolism. Dietary flavone played a significant role in growth performance, intestinal health and physiology of Litopenaeus vannamei.