Replacement of fishmeal by fermented soybean meal could enhance the growth performance but not significantly influence the intestinal microbiota of white shrimp Litopenaeus vannamei

Intestinal microbiota plays a vital role in nutrient metabolism, pathogen resistance and development of immune system. Here, an Illumina-based method was employed to investigate the intestinal microbiota in white shrimp fed diets with five replacement levels (0, 10, 20, 30 and 40%) of fishmeal by fermented soybean meal (FSM). The results of growth trail revealed that shrimp fed a diet with 20% replacement of fishmeal by FSM (FSM20) had significantly better growth performance. Based on the sequence analysis, we got a total of 2535 OTUs from all of samples. These OTUs were identified into 22 phyla, among which Proteobacteria was the most abundant one. The richness and diversity of intestinal microbiota were not changed by dietary different levels of FSM (P > .05). Results of functional prediction showed that membrane transport was the most abundant function matching in KEGG database at level 2. In terms of nutrition-related metabolism functions, there was no significant difference in all of dietary groups (P > .05). All the results above showed that dietary appropriate level of FSM (20%) could enhance the growth performance, but not affect intestinal microbiota of shrimp.