The Key Laboratory of Aquaculture Nutrition and Feeds (Ministry of Agriculture and Rural Affairs), The Key Laboratory of Mariculture (Ministry of Education), Fisheries College, Ocean University of China, Qingdao, 266003, China.
The Key Laboratory of Aquaculture Nutrition and Feeds (Ministry of Agriculture and Rural Affairs), The Key Laboratory of Mariculture (Ministry of Education), Fisheries College, Ocean University of China, Qingdao, 266003, China.
Fish Shellfish Immunol. 2023 Nov;142:109114. doi: 10.1016/j.fsi.2023.109114. Epub 2023 Sep 26.
Abalone Haliotis discus hannai (initial weight: 38.79 ± 0.70 g) was used as the experimental animal in a 105-day feeding trial to investigate the influence of dietary bile acids levels on the growth, anti-oxidation, immune response and intestinal microbiota. Six isonitrogenous and isolipidic diets were prepared by adding 0 (control group), 15, 30, 60, 120 and 240 mg/kg of bile acids, respectively (named BA0, BA15, BA30, BA60, BA120 and BA240, respectively). It was found that survival of abalone between groups had no significant difference (P > 0.05). Compared to the control, significant improvements in weight gain rate (WGR) were observed in the groups of BA30 and BA60 (P < 0.05). Based on WGR, the broken line regression model analysis showed that the optimum demand for dietary bile acids for abalone was 35.47 mg/kg. Dietary bile acids increased the total anti-oxidative capacity and activities of catalase, superoxide dismutase, lysozyme and alkaline phosphatase, meanwhile decreased the content of malondialdehyde, alanine aminotransferase and aspartate aminotransferase activities in the cell-free hemolymph (P < 0.05). When bile acids were added to the diets, mRNA levels of genes related to pro-inflammatory factors and apoptosis in the digestive gland were down-regulated (P < 0.05). In contrast, the expression of genes related to anti-oxidation was significantly up-regulated (P < 0.05). The Firmicutes, Actinobacteriota and Proteobacteria were the most abundant phyla in intestine. And dietary bile acids significantly decreased the abundance of Actinobacteria and increased the abundance of Firmicutes (P < 0.05). In conclusion, supplementation of dietary bile acids within 120 mg/kg significantly increased the growth of abalone. The 34.62 mg/kg of dietary bile acids significantly increased the anti-oxidative capacity of abalone. Appropriate levels of dietary bile acids (34.62-61.75 mg/kg) promote the immunity of abalone. Application of appropriate levels of bile acids in diets (34.62 mg/kg) changed the intestinal microbiota and promoted the intestinal health of abalone.
鲍（初始体重：38.79±0.70g）被用作为期 105 天的饲养试验中的实验动物，以研究膳食胆汁酸水平对生长、抗氧化、免疫反应和肠道微生物群的影响。通过添加 0（对照组）、15、30、60、120 和 240mg/kg 胆汁酸，分别制备了六种等氮和等脂的饲料（分别命名为 BA0、BA15、BA30、BA60、BA120 和 BA240）。结果发现，各组鲍的存活率无显著差异（P＞0.05）。与对照组相比，BA30 和 BA60 组的增重率（WGR）显著提高（P＜0.05）。基于 WGR，折线回归模型分析表明，鲍对膳食胆汁酸的最佳需求为 35.47mg/kg。膳食胆汁酸增加了总抗氧化能力和过氧化氢酶、超氧化物歧化酶、溶菌酶和碱性磷酸酶的活性，同时降低了无细胞血淋巴中丙二醛、丙氨酸转氨酶和天冬氨酸转氨酶活性的含量（P＜0.05）。当饲料中添加胆汁酸时，消化腺中与促炎因子和细胞凋亡相关的基因的 mRNA 水平下调（P＜0.05）。相反，与抗氧化相关的基因表达显著上调（P＜0.05）。厚壁菌门、放线菌门和变形菌门是肠道中最丰富的门。膳食胆汁酸显著降低了放线菌门的丰度，增加了厚壁菌门的丰度（P＜0.05）。总之，饲料中添加 120mg/kg 以内的胆汁酸可显著提高鲍的生长速度。饲料中 34.62mg/kg 的胆汁酸可显著提高鲍的抗氧化能力。适当水平的膳食胆汁酸（34.62-61.75mg/kg）可促进鲍的免疫力。饲料中添加适当水平的胆汁酸（34.62mg/kg）可改变肠道微生物群，促进鲍的肠道健康。
