Hou Tinglong, Tang Zhengxian, Wang Zuobo, Li Chuntao
Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Jinan University, Guangzhou, China.
College of Fisheries, Southwest University, Chongqing, China.
J Fish Biol. 2025 Feb;106(2):114-124. doi: 10.1111/jfb.15925. Epub 2024 Sep 13.
This study aimed to identify potential probiotic strains of Bacillus subtilis from healthy fish gut microbiota for application in aquaculture. The effects of dietary B. subtilis administration on growth performance, serum enzyme activity, immune gene expression, and disease resistance in darkbarbel catfish (Pelteobagrus fulvidraco) were investigated. The isolate, identified through gene sequencing and biochemical tests, demonstrated resilience to pH 3.0% and 6.0% bile, and exhibited extracellular protease, cellulose, lipase, and amylase production. Darkbarbel catfish were fed diets with varying B. subtilis concentrations (0 CFU/kg [T0], 10 CFU/kg [T1], 10 CFU/kg [T2], and 10 CFU/kg [T3]). After 8 weeks, significant increases (p < 0.05) were observed in final body weight, weight gain rate, specific growth rate, serum lysozyme, serum superoxide dismutase, alkaline phosphatase, and total antioxidant capacity, whereas malondialdehyde levels significantly decreased. Feeding darkbarbel catfish with B. subtilis diets increased immunoglobulin M (IgM) and C3 gene expression (p < 0.05), indicating a positive impact on the fish's immune system. The strain upregulated interleukin 10 (IL-10) and transforming growth factor-β (TGF-β) expression and downregulated TNF-α and IL-1β, suggesting potential anti-inflammatory effects. Following a 7-day challenge with Aeromonas hydrophila, fish fed with B. subtilis exhibited lower mortality, with higher survival rates in the T2 and T3 groups. In conclusion, supplementing darkbarbel catfish diets with B. subtilis effectively enhances growth performance, immune response, and disease resistance.
本研究旨在从健康鱼类肠道微生物群中鉴定潜在的枯草芽孢杆菌益生菌菌株，用于水产养殖。研究了饲料中添加枯草芽孢杆菌对黄颡鱼生长性能、血清酶活性、免疫基因表达和抗病能力的影响。通过基因测序和生化试验鉴定的分离株对pH 3.0%和6.0%的胆汁具有耐受性，并能产生细胞外蛋白酶、纤维素酶、脂肪酶和淀粉酶。给黄颡鱼投喂不同浓度枯草芽孢杆菌的饲料（0 CFU/kg [T0]、10 CFU/kg [T1]、10 CFU/kg [T2]和10 CFU/kg [T3]）。8周后，最终体重、增重率、特定生长率、血清溶菌酶、血清超氧化物歧化酶、碱性磷酸酶和总抗氧化能力显著增加（p < 0.05），而丙二醛水平显著降低。给黄颡鱼投喂枯草芽孢杆菌饲料可增加免疫球蛋白M（IgM）和C3基因表达（p < 0.05），表明对鱼类免疫系统有积极影响。该菌株上调白细胞介素10（IL-10）和转化生长因子-β（TGF-β）的表达，下调肿瘤坏死因子-α（TNF-α）和白细胞介素-1β（IL-1β），提示可能具有抗炎作用。在用嗜水气单胞菌进行7天攻毒后，投喂枯草芽孢杆菌的鱼死亡率较低，T2和T3组的存活率较高。总之，在黄颡鱼饲料中添加枯草芽孢杆菌可有效提高生长性能、免疫反应和抗病能力。
