Yuan Yi, Omar Amira A, Emam Wasseem, Mohamed Radi A
Department of Aquaculture, Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh University, Kafr El-Sheikh, Egypt.
Department of Fish Diseases and Management, Faculty of Veterinary Medicine, Kafrelsheikh University, Kafr El-Sheikh, Egypt.
Open Vet J. 2025 Jan;15(1):222-243. doi: 10.5455/OVJ.2025.v15.i1.21. Epub 2025 Jan 31.
Bile acids (BAs) are made from cholesterol in the liver and are then coupled with taurine or glycine before being expelled by the hepatocyte. BAs are very important for the emulsification of dietary fat for easy nutrient absorption processes.
The aim of this study is to investigate the effects of dietary BA supplementation and dietary fat percent on the growth performance, morphology of the intestine, immune-physiological responses, and transcriptomic responses of Nile tilapia ().
Using diets containing three different inclusion levels of fat (5%, 7%, and 9%) with or without BA supplementation (0.4 g/kg), fish were fed for 90 days.
BA supplementation significantly ( < 0.05) improved growth performance and feed utilization, with fish-fed BA-supplemented diets exhibiting higher final weight (FW), weight gain (WG), and feed conversion ratio. Dietary fat levels also significantly affected growth performance, with higher fat levels leading to higher FW, WG, and specific growth rate. BA supplementation also positively ( < 0.05) affected intestinal morphology, immune response, and antioxidant capacity. Fish-fed BA-supplemented diets had higher intestinal villus height, lysozyme activity, superoxide dismutase (SOD) and catalase (CAT) activities, and lower malonaldehyde concentration. Gene expression analysis revealed that BA supplementation upregulated ( < 0.05) the expression of antioxidant-related genes (SOD, glutathione peroxidase, and CAT, growth-related genes (GHr1 and insulin growth factor 1), and intestinal mucin gene (MUC2) while downregulating ( < 0.05) the expression of fatty acid synthase and pro-inflammatory genes (interleukin 1β and tumor necrosis factor alpha).
BA dietary supplementation accompanied with 7% fat can be a valuable tool for improving Nile tilapia's growth performance, feed utilization, intestinal health, immune function, and antioxidant capacity.
胆汁酸（BAs）在肝脏中由胆固醇合成，然后在被肝细胞排出之前与牛磺酸或甘氨酸结合。胆汁酸对于乳化膳食脂肪以促进营养吸收过程非常重要。
本研究旨在探讨日粮中添加胆汁酸和日粮脂肪百分比对尼罗罗非鱼生长性能、肠道形态、免疫生理反应和转录组反应的影响。
使用含有三种不同脂肪添加水平（5%、7%和9%）且添加或不添加胆汁酸（0.4 g/kg）的日粮，投喂鱼类90天。
添加胆汁酸显著（P<0.05）改善了生长性能和饲料利用率，投喂添加胆汁酸日粮的鱼表现出更高的终末体重（FW）、增重（WG）和饲料转化率。日粮脂肪水平也显著影响生长性能，较高的脂肪水平导致更高的FW、WG和特定生长率。添加胆汁酸还对肠道形态、免疫反应和抗氧化能力产生积极影响（P<0.05）。投喂添加胆汁酸日粮的鱼具有更高的肠绒毛高度、溶菌酶活性、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性，以及更低的丙二醛浓度。基因表达分析表明，添加胆汁酸上调了（P<0.05）抗氧化相关基因（SOD、谷胱甘肽过氧化物酶和CAT）、生长相关基因（GHr1和胰岛素生长因子1）以及肠道粘蛋白基因（MUC2）的表达，同时下调了（P<0.05）脂肪酸合酶和促炎基因（白细胞介素1β和肿瘤坏死因子α）的表达。
日粮中添加胆汁酸并搭配7%的脂肪可以成为提高尼罗罗非鱼生长性能、饲料利用率、肠道健康、免疫功能和抗氧化能力的有效手段。
