Caprioli Riccardo, Mrugała Agata, Di Domenico Marco, Curini Valentina, Giansante Carla, Cammà Cesare, Petrusek Adam
Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise 'G. Caporale', 64100 Teramo, Italy.
Dis Aquat Organ. 2018 Sep 27;130(3):209-219. doi: 10.3354/dao03275.
The oomycete Aphanomyces astaci is the causative agent of crayfish plague in native European freshwater crayfish. Molecular analyses showed that several distinct genotype groups of this pathogen, apparently associated with different original host taxa, are present in Europe. Tracking their distribution may contribute to understanding the introduction pathways of A. astaci. We used microsatellite markers to genotype the pathogen strains involved in 7 mass mortalities of the endangered indigenous crayfish Austropotamobius pallipes that occurred between 2009 and 2016 in the Abruzzi and Molise regions, central Italy. Three A. astaci genotype groups (A, B, and D, with the latter represented by 2 distinct multilocus genotypes) were identified, suggesting the existence of multiple infection sources even in a relatively small area. Most crayfish plague episodes were due to genotype groups associated with the North American host species Pacifastacus leniusculus and Procambarus clarkii, although these crayfish are not widespread in the study area. A. astaci genotype group A was detected not only in crayfish plague outbreaks but also in apparently healthy Astacus leptodactylus imported for human consumption from Armenia and kept alive in an aquaculture facility. Imports of chronically infected A. leptodactylus from Armenia, Turkey, and possibly Eastern Europe are an underestimated introduction pathway for A. astaci. Although we cannot exclude the presence of latently infected native populations of A. pallipes in the region, A. astaci infections in legally imported crayfish species considered vulnerable to crayfish plague may represent further reservoirs of A. astaci; this should be reflected in the policies regulating the trade of live crayfish.
卵菌纲的螯虾疫霉是欧洲本土淡水小龙虾发生小龙虾瘟疫的病原体。分子分析表明，这种病原体的几个不同基因型组在欧洲存在，显然与不同的原始宿主类群有关。追踪它们的分布可能有助于了解螯虾疫霉的引入途径。我们使用微卫星标记对2009年至2016年间发生在意大利中部阿布鲁佐和莫利塞地区的7起濒危本土小龙虾意大利螯虾大规模死亡事件中涉及的病原体菌株进行基因分型。鉴定出了3个螯虾疫霉基因型组（A、B和D，其中后者由2个不同的多位点基因型代表），这表明即使在相对较小的区域也存在多种感染源。大多数小龙虾瘟疫事件是由与北美宿主物种美洲螯虾和克氏原螯虾相关的基因型组引起的，尽管这些小龙虾在研究区域并不广泛。不仅在小龙虾瘟疫爆发中检测到了螯虾疫霉基因型组A，而且在从亚美尼亚进口用于人类消费并在水产养殖设施中存活的看似健康的窄指螯虾中也检测到了该基因型组。从亚美尼亚、土耳其以及可能的东欧进口慢性感染的窄指螯虾是螯虾疫霉一个被低估的引入途径。虽然我们不能排除该地区存在意大利螯虾潜在感染种群的可能性，但法律进口的易感染小龙虾瘟疫的小龙虾物种中的螯虾疫霉感染可能代表了螯虾疫霉的进一步储存宿主；这一点应在规范活小龙虾贸易的政策中得到体现。
