Domeneghetti Stefania, Varotto Laura, Civettini Michele, Rosani Umberto, Stauder Monica, Pretto Tobia, Pezzati Elisabetta, Arcangeli Giuseppe, Turolla Edoardo, Pallavicini Alberto, Venier Paola
Department of Biology, University of Padova, Padova, Italy.
Istituto Zooprofilattico Sperimentale delle Venezie (IZSVe, also NRL for Mollusc Diseases), Adria, Italy.
Fish Shellfish Immunol. 2014 Nov;41(1):37-44. doi: 10.1016/j.fsi.2014.05.023. Epub 2014 Jun 5.
The complex interactions occurring between farmed bivalves and their potential pathogens in the circumstances of global climate changes are current matter of study, owing to the recurrent production breakdowns reported in Europe and other regions of the world. In the frame of Project FP7-KBBE-2010-4 BIVALIFE, we investigated the occurrence of mortality and potential pathogens during the Spring-Summer transition in Crassostrea gigas and Mytilus galloprovincialis cohabiting in the shallow waters of one northern Italian lagoon (Sacca di Goro, Adriatic Sea) and regarded as susceptible and resistant species, respectively. In 2011, limited bivalve mortality was detected in the open-field trial performed with 6-12 month old spat whereas subsequent trials with 2-3 month old spat produced almost complete (2012) and considerable (2013) oyster mortality. Macroscopical examination and histology excluded the presence of notifiable pathogens but, in the sampling preceding the massive oyster spat mortality of 2012, a μdeleted variant of OsHV-1 DNA was found in wide-ranging amounts in all analyzed oysters in conjunction with substantial levels of Vibrio splendidus and Vibrio aestuarianus. The large oyster spat mortality with borderline OsHV-1 positivity recorded in 2013 supports the multi-factorial etiology of the syndrome. This is the first report of a OsHV-1 (under a form interpreted as the variant μVar) in the Goro lagoon. Transcriptional host footprints are under investigation to better understand the bivalve response to environmental factors, included viral and bacterial pathogens, in relation to the observed mortalities.
由于欧洲和世界其他地区报告的养殖生产反复中断，养殖双壳贝类与其潜在病原体在全球气候变化情况下发生的复杂相互作用是当前的研究课题。在FP7-KBBE-2010-4项目“双壳贝类生命”的框架内，我们调查了意大利北部一个泻湖（亚得里亚海的戈罗泻湖）浅水区中共同栖息的太平洋牡蛎和地中海贻贝在春夏季过渡期间的死亡情况及潜在病原体，这两种贝类分别被视为易感物种和抗性物种。2011年，在对6至12月龄的贝苗进行的野外试验中检测到有限的双壳贝类死亡，而随后对2至3月龄贝苗进行的试验导致了几乎完全（2012年）和相当数量（2013年）的牡蛎死亡。宏观检查和组织学排除了法定病原体的存在，但在2012年大量牡蛎贝苗死亡之前的采样中，在所有分析的牡蛎中都发现了大量的OsHV-1 DNA的μ缺失变体，同时伴有大量的灿烂弧菌和河口弧菌。2013年记录的牡蛎贝苗大量死亡且OsHV-1呈临界阳性支持了该综合征的多因素病因。这是戈罗泻湖中首次报告存在OsHV-1（以一种被解释为变体μVar的形式）。目前正在研究宿主转录足迹，以更好地了解双壳贝类对环境因素（包括病毒和细菌病原体）与观察到的死亡率相关的反应。
