胆汁酸和牛磺酸对大口黑鲈生长、肝脏健康及肠道屏障的影响OA北大核心CSTPCD

Micropterus salmoides is a significant species in China's aquaculture industry,offering considerable economic benefits.Diet and nutrition are crucial for addressing various issues in the aquaculture of M.salmoides,including growth,health and disease resistance.Bile acids and taurine are bioactive substances that participate in various biological and physiological processes in animals.To investigate the synergistic effects of bile acid and taurine in the M.salmoides diets,four isonitrogenous(46％)and isobaric(10％)experimental diets were designed respectively by adding 0.03％bile acid(BA),0.5％taurine(Tau),and 0.03％bile acid+0.5％taurine(BA+Tau)to the basal diet.M.salmoides,with an initial weight of(15.33±0.23)g,were reared in an indoor recirculating sys-tem for 8 weeks.The result indicated that the growth performance of M.salmoides significantly improved with the addition of bile acid and taurine,whether used separately or combined,while also reducing serum glucose(GLU),triglycerides(TG)and cholesterol(TC)levels,and activities of alanine aminotransferase(ALT)and aspartate aminotransferase(AST).Compared with the control group,the experimental group exhibited a signi-ficant increase in liver antioxidant enzyme activities—superoxide dismutase(SOD),catalase(CAT),and glutathione peroxidase(GSH-Px)—and a decreased malondialdehyde(MDA)levels.Additionally,mRNA expression of lycometabolic genes(gck,pklr,pygl,pck1)and lipid metabolism genes(cptl,acaca)in liver was regulated.Additionally,it decreased liver lipid and glycogen content and notably enhanced the hepatic histomor-phological structure.It significantly increased the activity of intestinal antioxidant enzymes(SOD,CAT,GSH-Px)and reduced the relative expression levels of intestinal pro-inflammatory cytokines(IL-1β,IL-8,and TNF-a).Fur-thermore,it elevated the relative expression level of the intestinal tight junction protein gene zo-1,and the bile acid and taurine combination notably upregulated claudin-1 and occludin-1.Moreover,the content of D-lactic acid(D-lac)and diamine oxidase(DAO)activity in serum in the bile acid group were significantly lower than those in con-trol group(basal diet).In conclusion,supplementing feed with bile acid and taurine,either individually or in com-bination,enhances liver and intestinal antioxidant capacity,modulates glycolipid metabolism,boosts immune func-tion,and fosters the growth of M.salmoides.The combination of bile acids and taurine exerts a synergistic effect on M.salmoides.