State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China; School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo University, Ningbo, 315211, China; School of Marine Sciences, Ningbo University, Ningbo, 315211, China.
Fish Shellfish Immunol. 2022 Aug;127:758-765. doi: 10.1016/j.fsi.2022.07.016. Epub 2022 Jul 11.
Shrimp diseases frequently occur during the later farming stages, when the rearing water is eutrophic. This observation provides clue that the virulence of pathogens could be induced by elevated nutrient, whereas the underlying ecological mechanism remains limited. To address this pressing knowledge, we explored how gut microbiota responded to the infection of oligotrophic (OVp) or eutrophic (EVp) pre-cultured Vibrio parahaemolyticus, a causing pathogen of shrimp acute hepatopancreatic necrosis disease (AHPND). Resulted revealed that OVp and EVp infections caused dysbiosis in the gut microbiota and compromised shrimp immunity, while the later infection led to earlier and higher mortality. Significant associations were detected between the gut microbiota and each of the measured immune activities. Neutral community model showed that the assembly of gut microbiota was more strongly governed by deterministic processes in EVp infection, followed by EVp infected and control shrimp. Additionally, there were significantly lower temporal turnover rate and average variation degree in the gut microbiota in EVp infected shrimp compared with control individuals. Notably, we identified 22 infection-discriminatory taxa after ruling out the ontogenic effect. Using profiles of the 22 indicators as independent variables, the diagnosis model accurately distinguished (an overall 85.9% accuracy) the infected status (control, OVp or EVp infected shrimp), with 81.3% accuracy at the initial infection stage. The convergent and deterministic gut microbiota in EVp infected shrimp could partially explain why it is challenge to cure APHND from an ecological viewpoint. In addition, we provided a sensitive approach for diagnosing the onset of infection, when disease symptom is unobservable.
在养殖后期，当养殖水富营养化时，虾类疾病经常发生。这一观察结果提供了一个线索，即病原体的毒力可能是由升高的营养物质诱导的，而潜在的生态机制仍然有限。为了解决这一紧迫的知识需求，我们探讨了肠道微生物群如何对贫营养（OVp）或富营养（EVp）预培养的副溶血弧菌的感染做出反应，副溶血弧菌是引起虾急性肝胰腺坏死病（AHPND）的病原体。结果表明，OVp 和 EVp 感染导致肠道微生物群失调和虾免疫力受损，而后者感染导致更早和更高的死亡率。在肠道微生物群和每个测量的免疫活性之间检测到显著的关联。中性群落模型表明，在 EVp 感染中，肠道微生物群的组装更受确定性过程的控制，其次是 EVp 感染和对照虾。此外，与对照个体相比，EVp 感染的虾中的肠道微生物群的时间周转率和平均变化程度明显较低。值得注意的是，我们在排除了个体发育效应后，鉴定出了 22 个与感染相关的分类群。使用这 22 个指标的特征作为自变量，该诊断模型准确地区分了（总准确率为 85.9%）感染状态（对照、OVp 或 EVp 感染的虾），在初始感染阶段的准确率为 81.3%。EVp 感染的虾中趋同和确定性的肠道微生物群可以部分解释为什么从生态角度来看，治愈 AHPND 具有挑战性。此外，我们提供了一种敏感的方法来诊断感染的开始，当疾病症状不可观察时。
