The combined probiotics (four different combination of Bacillus subtilis, Bacillus licheniformis and Enterococcus faecalis) were used and the growth performance, immunity, gut morphology and resistance to Streptococcus agalactiae of tilapia (Oreochromis mossambicus) were comprehensively evaluated after 42 days feeding on supplemented diets. Results showed that the growth performance of tilapia in PG2 (with B. subtilis and E. faecalis) was the best. Moreover, the strong positive association of some indices with specific probiotics was demonstrated for lipase activity, SI, LYZ, C3, T-AOC and CAT were higher in PG2, indicating that the specific probiotics, and not diversiform probiotics, were the key determinants of the results for tilapia. The better gut villi length, villi width and muscular thickness in fishes under PG2, which shows that specific probiotics can promote the good development of gut mucosal structure of tilapia. Over 76% survival rate for tilapias against S. agalactiae in the PG2 may be because the B. subtilis and E. faecalis provided a better gut micro-ecological environment. Totally, B. subtilis and E. faecalis may be specific to tilapia gut microbes.

中文翻译：

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日粮中添加枯草芽孢杆菌和粪肠球菌能有效提高罗非鱼的生长性能、免疫力和对无乳链球菌的抵抗力

使用组合益生菌（枯草芽孢杆菌、地衣芽孢杆菌和粪肠球菌四种不同组合），并在饲喂补充日粮 42 天后综合评估罗非鱼（Oreochromis mossambicus）的生长性能、免疫力、肠道形态和对无乳链球菌的抵抗力。结果表明，罗非鱼在 PG2 中的生长性能（与枯草芽孢杆菌和粪肠球菌） 是最好的。此外，脂肪酶活性的某些指标与特定益生菌呈强正相关，PG2 中的 SI、LYZ、C3、T-AOC 和 CAT 较高，表明特定益生菌而非多样化益生菌是影响脂肪酶活性的关键因素。罗非鱼的结果。PG2下鱼类的肠道绒毛长度、绒毛宽度和肌肉厚度较好，说明特定的益生菌可以促进罗非鱼肠道黏膜结构的良好发育。PG2 中罗非鱼对无乳链球菌的存活率超过 76%可能是因为枯草芽孢杆菌和粪肠球菌提供了更好的肠道微生态环境。完全，枯草芽孢杆菌和粪肠球菌 可能特定于罗非鱼肠道微生物。