Lopez-Joven Carmen, Rolland Jean-Luc, Haffner Philippe, Caro Audrey, Roques Cécile, Carré Claire, Travers Marie-Agnès, Abadie Eric, Laabir Mohamed, Bonnet Delphine, Destoumieux-Garzón Delphine
IHPE, Université de Montpellier, CNRS, Ifremer, UPVD, Montpellier, France.
MARBEC, Université de Montpellier, CNRS, Ifremer, IRD, Montpellier, France.
Front Microbiol. 2018 Oct 24;9:2530. doi: 10.3389/fmicb.2018.02530. eCollection 2018.
species have been associated with recurrent mass mortalities of juvenile oysters threatening oyster farming worldwide. However, knowledge of the ecology of pathogens in affected oyster farming areas remains scarce. Specifically, there are no data regarding (i) the environmental reservoirs of populations pathogenic to oysters, (ii) the environmental factors favoring their transmission, and (iii) the influence of oyster farming on the persistence of those pathogens. This knowledge gap limits our capacity to predict and mitigate disease occurrence. To address these issues, we monitored species potentially pathogenic to in 2013 and 2014 in the Thau Lagoon, a major oyster farming region in the coastal French Mediterranean. Sampling stations were chosen inside and outside oyster farms. Abundance and composition of phyto-, microzoo-, and mesozooplankton communities were measured monthly. The spatial and temporal dynamics of plankton and species were compared, and positive correlations between plankton species and vibrios were verified by qPCR on isolated specimens of plankton. was present in the water column over both years, whereas was mostly found in 2013 and was never detected. Moreover, and were found both as free-living or plankton-attached vibrios 1 month after spring mortalities of the oyster juveniles. Overall, was associated with temperature and plankton composition, whereas correlated with plankton composition only. The abundance of species in the water column was similar inside and outside oyster farms, suggesting important spatial dispersion of pathogens in surrounding areas. Remarkably, a major increase in and was measured in the sediment of oyster farms during cold months. Thus, a winter reservoir of pathogenic vibrios could contribute to their ecology in this Mediterranean shellfish farming ecosystem.
某些物种与幼体牡蛎的反复大规模死亡有关，这威胁着全球的牡蛎养殖。然而，在受影响的牡蛎养殖区域，关于病原体生态学的知识仍然匮乏。具体而言，目前尚无关于以下方面的数据：（i）对牡蛎致病的种群的环境储存库；（ii）有利于其传播的环境因素；（iii）牡蛎养殖对这些病原体持久性的影响。这一知识空白限制了我们预测和减轻疾病发生的能力。为了解决这些问题，我们于2013年和2014年在法国地中海沿岸的主要牡蛎养殖区陶湖监测了可能对牡蛎致病的物种。采样站选在牡蛎养殖场内外。每月测量浮游植物、微型浮游动物和中型浮游动物群落的丰度和组成。比较了浮游生物和弧菌物种的时空动态，并通过对分离的浮游生物标本进行qPCR验证了浮游生物物种与弧菌之间的正相关关系。两年间水柱中均存在[具体物种1]，而[具体物种2]大多在2013年被发现，[具体物种3]从未被检测到。此外，在牡蛎幼体春季死亡1个月后，[具体物种1]和[具体物种2]均以自由生活或附着于浮游生物的弧菌形式被发现。总体而言，[具体物种1]与温度和浮游生物组成有关，而[具体物种2]仅与浮游生物组成相关。水柱中弧菌物种的丰度在牡蛎养殖场内外相似，这表明病原体在周边地区有重要的空间扩散。值得注意的是，在寒冷月份，牡蛎养殖场沉积物中[具体物种1]和[具体物种2]的数量大幅增加。因此，致病弧菌的冬季储存库可能对这个地中海贝类养殖生态系统中的病原体生态学有贡献。
