Dietary Solid-state-fermentation product of Bacillus velezensis T23 alleviate hepatic steatosis, oxidative stress, gut barrier damage, and microbiota dysbiosis in juvenile genetically improved farmed tilapia (GIFT, Oreochromis niloticus)

作者：Qiang Hao, Rolf Erik Olsen, Einar Ringø, Qianwen Ding, Tsegay Teame, Yuanyuan Yao, Chao Ran, Yalin Yang, Zhen Zhang, Zhigang Zhou · 发表于：Aquaculture Reports · 年份：2024 · DOI：10.1016/j.aqrep.2024.102523 · 被引用次数：8 · 研究领域：Aquaculture Nutrition and Growth、GABA and Rice Research、Animal Nutrition and Physiology

The application of commensal probiotic bacteria is one of the preferable green feed additives for antibiotic substitution in aquaculture, while the application methods and detailed action mechanisms of commensal bacteria isolated from aquatic animals are not consistent with normal mammalian-derived probiotics. The purpose of this study was to evaluate the effects of solid-state fermentation product of autochthonous Bacillus velezensis T23 on improving hepatic steatosis, liver antioxidation capacity, gut injury and gut microbiota profile of genetically improved farmed tilapia (GIFT, Oreochromis niloticus ). The T23 probiotic was added to the basal diet at a level of 0.00, 0.05, 0.1, 0.2 and 0.3 g/kg to develop five experimental diets, respectively. After 4 weeks of the feeding trial, the results showed that T23 supplementation notably reduced the hepatocytes vacuolization and the content of liver TAGs by downregulated the mRNA expression of the lipogenesis gene ( fas ), while upregulated the mRNA expression of lipid degradation genes ( cpt1 and pparα ) ( p < 0.05). Compared with the control, the 0.3T23 group showed significantly upregulated expression levels of anti-inflammatory cytokine genes ( tgf-β and il-10 ) in the liver of the fish ( p < 0.05). Besides, the activities of antioxidase SOD and CAT were significantly upregulated in T23 treatment groups, compared with the control ( p < 0.05). Fish groups fed with 0.2 g/kg and 0.3 g/kg T23 supplemented diet also exhibited sign...