Food Biotechnology Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Phahonyothin Rd., Pathumthani, 12120, Thailand.
Food Biotechnology Laboratory, National Center for Genetic Engineering and Biotechnology (BIOTEC), 113 Phahonyothin Rd., Pathumthani, 12120, Thailand.
Fish Shellfish Immunol. 2019 Mar;86:4-13. doi: 10.1016/j.fsi.2018.11.010. Epub 2018 Nov 10.
The use of probiotics in aquaculture is a practical alternative to promote animal health and disease prevention. Meanwhile, this practice can also reduce the use of prophylactic antibiotics. The purpose of this study was to identify candidate probiotics that could control pathogen populations in host's gastrointestinal (GI) tract and stimulate host immunity in shrimp aquaculture. Bacillus aryabhattai TBRC8450, a bacterial strain isolated from the environment in a shrimp farm, has an antimicrobial activity against many pathogenic strains of Vibrio harveyi and V. parahaemolyticus. Supplementation of B. aryabhattai to Pacific white shrimp (Litopenaeus vannamei) not only decreased the abundance of Vibrio populations, but also shifted the bacterial community in the shrimp GI tract. We found that supplementation of B. aryabhattai triggered shrimp innate immunity and antioxidant activities. mRNA expression of genes encoding microbial peptides and antioxidant enzymes, including C-type lectin, penaeidin-3, heat shock protein 60, thioredoxin, and ferritin, was significantly upregulated in the hepatopancreas of shrimp fed B. aryabhattai. Furthermore, phenoloxidase activity in the hemocytes and the total antioxidant activity in the plasma were increased, indicating enhanced immune and antioxidant responses at the systemic level. In contrast, supplementation of B. aryabhattai had no effect on the total hemocyte count and superoxide dismutase activity in the plasma and hepatopancreas. Importantly, a pathogen challenge test using V. harveyi 1562 showed a significant increase in survival rates of shrimp fed B. aryabhattai compared to the control group. Our findings suggest that B. aryabhattai TBRC8450 can likely be used as a probiotic to reduce the population of V. harveyi in the shrimp GI tract and to enhance shrimp innate immunity and antioxidant capacity for vibriosis resistance in shrimp aquaculture.
在水产养殖中使用益生菌是一种促进动物健康和预防疾病的实用方法。同时，这种做法还可以减少预防性抗生素的使用。本研究的目的是鉴定能够控制宿主胃肠道（GI）中病原体种群并刺激虾类水产养殖中宿主免疫力的候选益生菌。从虾养殖场环境中分离的细菌菌株芽孢杆菌（Bacillus aryabhattai）TBRC8450 对许多致病性哈维氏弧菌（Vibrio harveyi）和副溶血弧菌（V. parahaemolyticus）菌株具有抗菌活性。向凡纳滨对虾（Litopenaeus vannamei）补充芽孢杆菌不仅降低了弧菌种群的丰度，还改变了虾 GI 道中的细菌群落。我们发现，补充芽孢杆菌触发了虾的先天免疫和抗氧化活性。在虾肝胰腺中，编码微生物肽和抗氧化酶的基因的 mRNA 表达，包括 C 型凝集素、对虾肽-3、热休克蛋白 60、硫氧还蛋白和铁蛋白，显著上调。此外，血细胞酚氧化酶活性和血浆总抗氧化活性增加，表明系统水平的免疫和抗氧化反应增强。相比之下，补充芽孢杆菌对血浆和肝胰腺中的总血细胞计数和超氧化物歧化酶活性没有影响。重要的是，用哈维氏弧菌 1562 进行的病原体攻毒试验表明，与对照组相比，饲喂芽孢杆菌的虾的存活率显著提高。我们的研究结果表明，芽孢杆菌 TBRC8450 可能可用作益生菌，以减少虾 GI 道中哈维氏弧菌的种群，并增强虾的先天免疫和抗氧化能力，以抵抗虾类水产养殖中的弧菌病。
