Large-scale intensive feeding triggered reduced growth performance and nutritional value. Exogenous probiotics can promote the growth performance and nutritional value of fish through improving the intestinal microbiota. However, detailed research on the correlation between the intestinal microbiota, growth performance, and nutritional value remains to be elucidated. Therefore, we performed metagenomic and metabolomic analysis to investigate the effects of probiotic addition to basal diet (1.0 × 10⁸ CFU/g) (PF) and water (1.0 × 10⁸ CFU/g) (PW) on the growth performance, muscle nutritional value, intestinal microbiota and their metabolites, and glucolipid metabolism in Coilia nasus. The results showed that FBW, BL, and SGR were enhanced in PF and PW groups. The concentrations of EAAs, TAAs, SFAs, MUFAs, and PUFAs were increased in PF and PW groups. Metagenomic and metabolic analyses revealed that bacterial community structure and metabolism were changed in the PF and PW groups. Moreover, adding probiotics to diet and water increased SCFAs and bile acids in the intestine. The gene expression associated with lipolysis and oxidation (hsl, pparα, cpt1, and acadm) and glycolysis (gck and pfk) was upregulated, while the gene expression associated with lipid synthesis (srebp1, acc, dgat, and elovl6) and gluconeogenesis (g6pca1, g6pca2, and pck) was downregulated in the liver. Correlation analysis displayed that hepatic glucolipid metabolism was regulated through the microbiota-gut-liver axis. Mantel test analysis showed that growth performance and muscle nutritional value were improved by the gut-liver axis. Our findings offered novel insights into the mechanisms that underlie the enhancement of growth performance and nutritional value in C. nasus and other fish by adding probiotics.

Keywords: Coilia nasus; glucolipid metabolism; growth performance; gut–liver axis; nutritional value; probiotics.

大规模集约化饲养导致了生长性能和营养价值的下降。外源性益生菌可以通过改善肠道微生物群来促进鱼类的生长性能和营养价值。然而，关于肠道微生物群、生长性能和营养价值之间相关性的详细研究仍有待阐明。因此，我们进行了宏基因组学和代谢组学分析，以探究在泥鳅（Coilia nasus）中添加基础饲料（1.0 × 10⁸ CFU/g）（PF组）和水中益生菌（1.0 × 10⁸ CFU/g）（PW组）对生长性能、肌肉营养价值、肠道微生物群及其代谢物以及糖脂代谢的影响。结果显示，与对照组相比，PF组和PW组的终末体重（FBW）、体长（BL）和特定生长率（SGR）均有所提高。PF组和PW组中必需氨基酸（EAAs）、总氨基酸（TAAs）、饱和脂肪酸（SFAs）、单不饱和脂肪酸（MUFAs）和多不饱和脂肪酸（PUFAs）的浓度也有所增加。宏基因组学和代谢分析表明，细菌群落结构和PF组及PW组中的代谢发生了变化。此外，在肠道中添加益生菌增加了短链脂肪酸（SCFAs）和胆汁酸的含量。与脂解和氧化相关的基因表达（如hsl、pparα、cpt1 和 acadm）上调，而与脂质合成（如srebp1、acc、dgat 和 elovl6）以及糖异生（如g6pca1、g6pca2 和 pck）相关的基因表达下调。相关性分析显示，肝脏的糖脂代谢是通过微生物群-肠道-肝脏轴进行调节的。曼特尔检验表明，生长性能和肌肉营养价值可以通过肠道-肝脏轴得到改善。我们的研究结果为在泥鳅和其他鱼类中添加益生菌提高生长性能和营养价值的机制提供了新的见解。

关键词：Coilia nasus；糖脂代谢；生长性能；肠道-肝脏轴；营养价值；益生菌。