Zhang Wenqian, Zhu Zidong, Chen Jiong, Qiu Qiongfen, Xiong Jinbo
State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products, Ningbo University, Ningbo, China.
School of Marine Sciences, Ningbo University, Ningbo, China.
Front Microbiol. 2021 Oct 8;12:752750. doi: 10.3389/fmicb.2021.752750. eCollection 2021.
Intensive studies have evaluated abiotic factors in shaping host gut microbiota. In contrast, little is known on how and to what extent abiotic (geochemical variables) and biotic (i.e., surrounding microbes, younger shrimp, and age) factors assemble the gut microbiota over shrimp ontogeny. Considering the functional importance of gut microbiota in improving host fitness, this knowledge is fundamental to sustain a desirable gut microbiota for a healthy aquaculture. Here, we characterized the successional rules of both the shrimp gut and rearing water bacterial communities over the entire shrimp farming. Both the gut and rearing water bacterial communities exhibited the time decay of similarity relationship, with significantly lower temporal turnover rate for the gut microbiota, which were primarily governed by shrimp age (days postlarval inoculation) and water pH. Gut commensals were primary sourced (averaged 60.3%) from their younger host, rather than surrounding bacterioplankton (19.1%). A structural equation model revealed that water salinity, pH, total phosphorus, and dissolve oxygen directly governed bacterioplankton communities but not for the gut microbiota. In addition, shrimp gut microbiota did not simply mirror the rearing bacterioplankton communities. The gut microbiota tended to be governed by variable selection over shrimp ontogeny, while the rearing bacterioplankton community was shaped by homogeneous selection. However, the determinism of rare and stochasticity of abundant subcommunities were consistent between shrimp gut and rearing water. These findings highlight the importance of independently interpreting host-associated and free-living communities, as well as their rare and abundant subcommunities for a comprehensive understanding of the ecological processes that govern microbial successions.
深入研究评估了非生物因素对宿主肠道微生物群的塑造作用。相比之下，关于非生物（地球化学变量）和生物（即周围微生物、幼虾和年龄）因素如何以及在多大程度上在对虾个体发育过程中组装肠道微生物群，我们知之甚少。考虑到肠道微生物群在提高宿主健康状况方面的功能重要性，这些知识对于维持健康水产养殖所需的肠道微生物群至关重要。在这里，我们描述了对虾养殖全过程中对虾肠道和养殖水体细菌群落的演替规律。肠道和养殖水体细菌群落均表现出相似性关系的时间衰减，肠道微生物群的时间周转率显著较低，其主要受对虾年龄（幼体接种后天数）和水体pH值的影响。肠道共生菌主要（平均60.3%）来源于其幼体宿主，而非周围的浮游细菌（19.1%）。结构方程模型显示，水体盐度、pH值、总磷和溶解氧直接影响浮游细菌群落，但对肠道微生物群没有影响。此外，对虾肠道微生物群并非简单地反映养殖水体中的浮游细菌群落。在对虾个体发育过程中，肠道微生物群倾向于受可变选择的影响，而养殖水体中的浮游细菌群落则受同质选择的影响。然而，对虾肠道和养殖水体中稀有亚群落的随机性和丰富亚群落的确定性是一致的。这些发现凸显了独立解读宿主相关群落和自由生活群落及其稀有和丰富亚群落对于全面理解控制微生物演替的生态过程的重要性。
