Mud crab Scylla paramamosain (S. paramamosain) is an economically important marine crab species around the world. White spot syndrome virus (WSSV) and Aeromonas hydrophila (AH) are pathogens during mud crab mariculture. It has been reported that gut microbiota possessed a great impact on the host development, nutrition, immunity, and disease resistance. However, little information was known about the impacts of WSSV or AH infection on the structure, composition, and function of the gut microbiotain of mud crabs. In this study, the gut microbiota of mud crabs infected with A. hydrophila and WSSV were characterized. The results showed that the composition and bacteria correlation of the gut microbiota were significantly decreased. During A. hydrophila infection, the pathogens played a major regulatory role in host. While in the mud crabs infected with WSSV, many beneficial strains had a great impact on the host expect for the pathogens. Therefore, our study revealed the effect of pathogens infection on gut microbiota of mud crabs and clarified the difference between viral infection and bacterial infection.

泥蟹Scylla paramamosain（S. paramamosain）是全世界经济上重要的海洋蟹种。白斑综合症病毒（WSSV）和嗜水气单胞菌（AH）是泥蟹海水养殖期间的病原体。据报道，肠道菌群对宿主的发育，营养，免疫力和抗病性具有很大的影响。但是，关于WSSV或AH感染对泥蟹肠道微生物区的结构，组成和功能的影响知之甚少。在这项研究中，泥浆的肠道菌群螃蟹感染嗜水气单和WSSV被表征。结果表明，肠道菌群的组成和细菌相关性明显降低。在嗜水链球菌感染期间，病原体在宿主中起主要调节作用。在感染了WSSV的泥蟹中，许多有益菌株对寄主对病原体的期望产生了很大影响。因此，我们的研究揭示了病原体感染对泥蟹肠道菌群的影响，并阐明了病毒感染和细菌感染之间的区别。