Abstract：
The most frequent causative agent of diphyllobothriosis, a fish-borne parasitic zoonosis, is the broad fish tapeworm Dibothriocephalus latus distributed mainly throughout the Holarctic region. The larval stages of the tapeworm were also detected in native and introduced freshwater fish in several lakes in South America, particularly in the north-western Patagonia in Argentina. The main objective of the present study was to determine the genetic structure of D. latus from rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta), and brook trout (Salvelinus fontinalis) from Gutiérrez Lake and Alicura Reservoir in Argentina using the sequences of three mitochondrial genes (cox1, cob, and nad3) and six polymorphic microsatellite loci. The results were compared with the corresponding molecular data of D. latus from Europe (Switzerland and Italy; the Alpine lakes region) and Asia (Siberia, Russia). Only one concatenated haplotype identical with the con-Ha1 specific for D. latus from the Alpine lakes region was detected in all individuals from Argentina. Three different alleles were detected in five out of six analysed microsatellite loci, indicating the presence of three sets of chromosomes. The same structure of microsatellite loci was recently observed in D. latus from Switzerland and Italy, in which triploidy was previously confirmed by cytogenetic study. The data on the mitochondrial genes, the allelic structure of microsatellite loci, and the principal coordinate analysis showed close genetic relationships between D. latus from Argentina and the Alpine lakes region, thus supporting the hypothesis of the European origin of the broad fish tapeworm from South America.
摘要：
最常见的二叶性关节炎病原体，鱼类传播的寄生虫人畜共患病，是主要分布在整个北极地区的广泛的鱼类a虫。在南美几个湖泊的本地和引入的淡水鱼中也检测到了tape虫的幼虫阶段，特别是在阿根廷的巴塔哥尼亚西北部。本研究的主要目的是确定虹鳟鱼（Oncorhynchusmykiss）的D.latus的遗传结构，褐鳟鱼（Salmotrutta），和来自阿根廷古铁雷斯湖和阿利库拉水库的鳟鱼（Salvelinusfontinalis）使用三个线粒体基因的序列（cox1，cob，和nad3）和六个多态微卫星位点。将结果与来自欧洲（瑞士和意大利；高山湖泊地区）和亚洲（西伯利亚，俄罗斯）。在来自阿根廷的所有个体中，仅检测到一种与来自高山湖泊地区的D.latus特异性的con-Ha1相同的串联单倍型。在六个分析的微卫星基因座中的五个中检测到三个不同的等位基因，表明三套染色体的存在。最近在瑞士和意大利的D.latus中观察到了相同的微卫星基因座结构，其中三倍体先前已通过细胞遗传学研究证实。线粒体基因的数据,微卫星位点的等位基因结构，主坐标分析表明，阿根廷的D.latus与高山湖泊地区的亲缘关系密切，因此支持了来自南美的广泛鱼类tape虫的欧洲起源的假设。
