The destruction of microbial communities within the gut of farmed tilapia (Oreochromis mossambicus) by Streptococcus agalactiae infection can result in considerable impacts to the health of the host. It is necessary to find a more effective treatment to improve the gut biome of farmed tilapia. We applied a tilapia culture method incorporating microorganisms in the diet and tracked gut bacteria over a 15-week period. A model of S. agalactiae infected individuals was constructed by detecting blood parameters and actual observation. Good’s coverage index (> 0.98) and < 1 % of reads was indicated by rarefaction curves. Healthy fish with no inclusion of microorganisms in the diet as reference group (RG), we assessed the effects of microorganisms on gut bacterial profiles and described changes in microbial richness and diversity via a comparison of the gut microbiota profiles of infected tilapia with (PD) and without (CG) the addition of microorganisms. An abnormal gut bacterial profile was associated with higher prevalence of infection by S. agalactiae, the lower Vibrio in PDs compared to the CGs, Spongiimonas spp. was present in all PDs and in the 3- and 6-week CGs, Photobacterium spp. appeared in all CGs and in the PDs at 3 and 6 weeks, Synechococcus, Shewanella, Spirochaeta, Psychromonas, Psychrilyobacter, Kiloniella, Allofrancisella, Candidatus Hepatoplasma, and Aliivibrio genera were only observed in the PDs, but Carboxylicivirga and Arcobacter were only detected in the CGs. Infected fish cultured using the combined microorganisms displayed significantly greater gut microbial species richness and diversity (Chao1; p-value < 0.001. Shannon’s; p-value < 0.001). The survival ratio of PDs (> 60 %) were higher than CGs. The application of the combined microorganisms within the diet of cultured O. mossambicus may therefore benefit their health by promoting a gut microbiome of greater diversity and increasing their resistance to disease.

无乳链球菌感染破坏了养殖罗非鱼（莫桑比克罗非鱼）肠道内的微生物群落，可能对寄主的健康产生重大影响。有必要找到一种更有效的方法来改善养殖罗非鱼的肠道生物群系。我们应用了罗非鱼培养方法，在15周内将微生物掺入了饮食中并追踪了肠道细菌。无乳链球菌的模型通过检测血液参数和实际观察来构造感染的个体。稀疏度曲线表明Good's的覆盖指数（> 0.98）和<1％的读数。饮食中未包含微生物的健康鱼作为参考组（RG），我们通过比较感染的罗非鱼和（PD）的肠道微生物区系，评估了微生物对肠道细菌谱的影响并描述了微生物丰富度和多样性的变化。且不添加（CG）微生物。肠道细菌的异常分布与无乳链球菌感染的发生率较高，PDs的弧菌水平低于CGs，海绵状菌的水平有关。存在于所有PD和在3-和6周的羧基，发光杆菌spp。出现在所有的羧基和在3周和6周，将PD聚球蓝细菌，希瓦氏菌属，螺旋体，Psychromonas，Psychrilyobacter，Kiloniella，Allofrancisella，暂定Hepatoplasma和Aliivibrio属只在PDS观察到，但Carboxylicivirga和弓形杆菌在只检测到CG。使用合并的微生物培养的受感染鱼显示出明显更大的肠道微生物物种丰富度和多样性（Chao1；p值<0.001。Shannon's；p-值<0.001）。PD的存活率（> 60％）高于CG。因此，通过培养具有更大多样性的肠道微生物组并增加其对疾病的抵抗力，将合并的微生物应用于培养的莫桑比克罗非鱼的饮食中可能有益于它们的健康。