LAUSR

Abstract Males of the giant freshwater prawn (GFP), Macrobrachium rosenbergii, have been staged histologically into three morphotypes: small male (SM), orange claw (OC), and blue claw (BC). At present, the social population structure is the main limited factor of yield and profitability in commercial GFP production. The aim of this study is to investigate the relationship between the intestinal microbiota and the three male morphotypes of GFP. In this study, we quantified bacterial communities and abdominal muscle transcriptomes by parallel 16S rRNA gene amplicon sequencing and RNA-Seq in three male morphotypes of GFP. The abundance of bacteria varied significantly with three male morphotypes. Moreover, we identified 6062 differentially expressed genes and found a pattern of gene expression involved in developmental stages from the small male via the orange claw to the blue claw morphotype. Eleven signal transduction pathways classified into environmental information processing were related to the frequency of the different male morphotypes in the prawn population. Furthermore, the correlation analysis identified that p53, AMPK, MO25, and ATG1 gene expressions were positively correlated with the abundance of Candidatus Hepatoplasma and negatively correlated with the Lactococcus and Bacillus population in the giant freshwater prawn. We revealed an intimate linkage between the intestinal microbiome and morphotypic differentiation in the males of GFP. This study also provides a more effective method to manipulate the frequency of the different male morphotypes in the male prawn population.