This study was conducted to investigate the effects of replacing fish meal (FM) with fermented soybean meal (FSM) and soybean meal (SM) on growth performance, intestinal histology and microbiota of largemouth bass (Micropterus salmoides). The basal diet contained 350 g/kg FM (CON), and then, FM was replaced with SM and FSM at the ratios of 30% and 60% (SM‐30, SM‐60, FSM‐30 and FSM‐60), respectively. The largemouth bass (4.43 ± 0.13 g) were fed for 8 weeks. The results showed that weight gain of fish fed with FSM‐60 and SM‐60 diets was significantly lower, and feed conversion ratio of SM‐30, SM‐60 and FSM‐60 groups was significantly higher than the CON group (p < .05). The intestinal villus height of SM‐60 group and the villus width of SM‐60 and FSM‐60 group were significantly lower than the CON group (p < .05). The 30% FM replacement by SM and FSM significantly increased the abundance of Cetobacterium and Mycoplasma, respectively (p < .05). In conclusion, FSM could replace 30% FM in diet without negative impacts on the growth performance of largemouth bass, while the SM should be controlled below 30%.

中文翻译：

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鱼粉代替发酵豆粕对大嘴鲈生长性能，肠道组织学和微生物区系的影响

本研究旨在研究用发酵豆粕（FSM）和豆粕（SM）代替鱼粉（FM）对大嘴鲈（Micropterus salmoides）的生长性能，肠道组织学和微生物群的影响。基础饮食含有350 g / kg FM（CON），然后以30％和60％的比例（SM-30，SM-60，FSM-30和FSM-60）将SM和FSM代替FM，分别。大口黑鲈（4.43±0.13 g）被喂食8周。结果表明，饲喂FSM-60和SM-60饲料的鱼的增重明显较低，SM-30，SM-60和FSM-60组的饲料转化率显着高于CON组（p <.05）。SM-60组的肠绒毛高度以及SM-60和FSM-60组的绒毛宽度均显着低于CON组（p  <.05）。用SM和FSM替代FM的30％分别显着增加了Cetobacterium和Mycoplasma的丰度（p  <.05）。总之，FSM可以代替日粮中30％的FM，而对大口黑鲈的生长性能没有负面影响，而SM应控制在30％以下。