Abstract: Virus diseases cause serious damages to Chinese aquaculture industry, but there is no effective countermeasure yet. Recent studies have confirmed the involvement of intestinal microflora in the interaction between host and viruses. However, there are rare related studies on fish. Germ-free (GF) animal infection model is the prerequisite for investigation of intestinal microflora-related functions. Based on this, a stable and reliable GF zebrafish model for spring viraemia of carp virus (SVCV) infection was established. Further, this model was used to investigate the influence of intestinal microflora and 3 strains of representative commensal intestinal bacteria, including Cetobacterium somerae, Aeromonas veronii and Plesimonas shigelloides, on viral infection in zebrafish. The results showed that there was no significant influence of intestinal microflora or commensal bacteria on SVCV infection after bacteria colonizing the intestinal tract of fish over 24 h. The establishment of a GF zebrafish model for SVCV infection provided a new way for rapidly screening the bacterial strains which could affect virus infection. The study also provided a possibility for further identification of the antiviral effectors derived from commensal bacteria of fish.

Key words: germ-free zebrafish, virus infection model, spring viraemia of carp virus, intestinal microflora

摘要： 我国水产养殖业受病毒危害严重，但目前尚无有效的应对手段。近年来研究证实，肠道菌群是宿主和病毒互作的参与者，然而鱼类的相关研究较少。无菌动物感染模型是研究肠道菌群相关功能的前提。基于此，以模式生物斑马鱼为研究对象，建立了稳定的无菌斑马鱼鲤春病毒血症病毒（spring viraemia of carp virus，SVCV）感染模型，并利用该感染模型探究斑马鱼肠道菌群和3株代表性的肠道土著菌对病毒感染的影响，包括鲸杆菌（Cetobacterium somerae）、维氏气单胞菌（Aeromonas veronii）及类志贺邻单胞菌（Plesimonas shigelloides）。研究结果显示，经菌鱼互作24 h，未观察到肠道菌群和代表菌株对病毒感染的影响。无菌斑马鱼病毒感染模型的建立为快速筛选影响病毒感染的菌株提供了一条新的途径，并为进一步探寻和开发细菌的潜在抗病毒效应元件提供了可能。

关键词: 无菌斑马鱼, 病毒感染模型, 鲤春病毒血症病毒, 肠道菌群