College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, USA
College of Earth, Ocean, and Atmospheric Sciences, Oregon State University, Corvallis, Oregon, USA.
Appl Environ Microbiol. 2018 Apr 16;84(9). doi: 10.1128/AEM.02156-17. Print 2018 May 1.
spp. have been a persistent concern for coastal bivalve hatcheries, which are vulnerable to environmental pathogens in the seawater used for rearing larvae, yet the biogeochemical drivers of oyster-pathogenic spp. in their planktonic state are poorly understood. Here, we present data tracking oyster-pathogenic bacteria in Netarts Bay and Yaquina Bay in Oregon, USA, as well as in adjacent coastal waters and a local shellfish hatchery, through the 2015 upwelling season. populations were quantified using a culture-independent approach of high-throughput specific 16S rRNA gene sequencing paired with droplet digital PCR, and abundances were analyzed in the context of local biogeochemistry. The most abundant putative pathogen in our samples was Environmental concentrations of total spp. and were highest in Netarts Bay sediment samples and higher in seawater from Netarts Bay than from nearshore coastal waters or Yaquina Bay. In Netarts Bay, the highest concentrations were observed during low tide, and abundances increased throughout the summer. We hypothesize that the warm shallow waters in estuarine mudflats facilitate the local growth of the pathogen. Samples from larval oyster tanks in Whiskey Creek Shellfish Hatchery, which uses seawater pumped directly from Netarts Bay, contained significantly lower total species concentrations, but roughly similar concentrations, than did the bay water, resulting in a 30-fold increase in the relative abundance of the pathogen in hatchery tanks. This suggests that the pathogen is able to grow or persist under hatchery conditions. It has been argued that oyster-pathogenic spp. have contributed to recent mortality events in U.S. shellfish hatcheries (R. A. Elston, H. Hasegawa, K. L. Humphrey, I. K. Polyak, and C. Häse, Dis Aquat Organ 82:119-134, 2008, https://doi.org/10.3354/dao01982); however, these events are often sporadic and unpredictable. The success of hatcheries is critically linked to the chemical and biological composition of inflowing seawater resources; thus, it is pertinent to understand the biogeochemical drivers of oyster-pathogenic spp. in their planktonic state. Here, we show that Netarts Bay, the location of a local hatchery, is enriched in oyster-pathogenic compared to coastal seawater, and we hypothesize that conditions in tidal flats promote the local growth of this pathogen. Furthermore, appears to persist in seawater pumped into the local hatchery. These results improve our understanding of the ecology and environmental controls of the pathogen and could be used to improve future aquaculture efforts, as multiple stressors impact hatchery success.
spp. 一直是沿海双壳贝类孵化场的一个持续关注的问题，因为孵化场的幼虫养殖用水容易受到环境病原体的影响，但浮游状态下牡蛎病原体 spp. 的生物地球化学驱动因素还了解甚少。在这里，我们通过 2015 年上升流季节，展示了美国俄勒冈州内塔兹湾和雅基马湾以及相邻沿海水域和当地贝类孵化场的牡蛎病原体细菌的数据。通过高通量特异性 16S rRNA 基因测序与液滴数字 PCR 相结合的非培养方法来定量 种群，并根据当地生物地球化学进行分析。我们样本中最丰富的假定病原体是 环境中总 spp. 和 的浓度在纳塔兹湾沉积物样本中最高，在纳塔兹湾的海水中比近岸海域或雅基马湾的海水中更高。在内塔兹湾，最低潮时观察到最高的 浓度，并且整个夏季的丰度都在增加。我们假设河口泥滩温暖的浅水有利于本地 病原体的生长。从 Whiskey Creek 贝类孵化场的幼虫牡蛎罐中采集的样本中，使用直接从纳塔兹湾抽取的海水，总 物种浓度明显较低，但与海湾水大致相似，导致孵化场罐中 病原体的相对丰度增加了 30 倍。这表明该 病原体能够在孵化条件下生长或存活。有人认为，牡蛎病原体 spp. 对美国贝类孵化场的最近的死亡事件有贡献（R. A. Elston、H. Hasegawa、K. L. Humphrey、I. K. Polyak 和 C. Häse，Dis Aquat Organ 82:119-134, 2008，https://doi.org/10.3354/dao01982）；然而，这些事件往往是零星的和不可预测的。孵化场的成功与流入海水资源的化学和生物组成密切相关；因此，了解浮游状态下牡蛎病原体 spp. 的生物地球化学驱动因素是很重要的。在这里，我们表明，与沿海海水相比，当地孵化场所在地的内塔兹湾富含牡蛎病原体，我们假设潮汐滩涂的条件促进了这种病原体的本地生长。此外， 似乎在抽到当地孵化场的海水中持续存在。这些结果提高了我们对 病原体的生态学和环境控制的理解，并可用于改进未来的水产养殖工作，因为多种胁迫因素会影响孵化场的成功。
