PDF(Pubmed)
Abstract：
Nematode parasites of the genus Anisakis (Nematoda, Anisakidae) are considered among the most important biological hazards in seafood products worldwide. In temperate and tropical waters, the most common species appears to be Anisakis typica, generally found around the viscera and sporadically in the flesh of various fish host species. This study investigated the infection sites and genetic diversity of A. typica infecting commercial fishes from the South-West Indian Ocean. Largehead hairtail (N = 20) and brushtooth lizardfish (N = 72) fished off Tanzania were inspected for anisakid nematodes by UV-press. A subsample of 168 nematodes were identified by sequence analyses of the cox2 mtDNA gene and ITS region of rDNA. The species A. typica (s.l.) (N = 166), Pseudoterranova ceticola (N = 1) and Anisakis paggiae (N = 1) were molecularly identified. Phylogenetic analysis of A. typica (s.l.) sequences based on both genes, indicated the existence of two distinct phylogenetic lineages forming two well-supported clades. The first clade comprised 12 A. typica specimens including individuals from its type locality (central Atlantic Ocean). The second clade comprising 154 specimens, clustered with reference sequences retrieved from GenBank including one apparently undescribed taxon, i.e., Anisakis sp. 1, and A. typica var. indonesiensis. The two reciprocally monophyletic clades are closely related and correspond to two distinct sister species within A. typica (s.l.), presently indicated as A. typica sp. A and A. typica sp. B. Two and four fixed alternative nucleotide substitutions (SNPs), i.e., diagnostic positions, between the two taxa, respectively, were found at the mtDNA cox2 and the ITS region of rDNA. The genetic data, as well as their occurrence in sympatry, strengthens the hypothesis that the actual specimens represent two distinct gene pools. The occurrence of both A. typica sp. A and A. typica sp. B in the musculature of freshly examined T. lepturus and S. undosquamis, suggests that both species can migrate intra-vitam into the flesh. Although the zoonotic potential of A. typica s.l. is still unclear, the presence of these parasites in the musculature, edible part of the fish, raises health concerns for consumers.
摘要：
Anisakis属线虫寄生虫（Nematoda，异株科）被认为是全球海产品中最重要的生物危害之一。在温带和热带水域，最常见的物种似乎是典型的异语，通常在各种鱼类宿主物种的内脏和肉中偶尔发现。这项研究调查了西南印度洋感染商品鱼类的感染部位和遗传多样性。通过紫外线印刷机检查了在坦桑尼亚捕捞的大头带鱼（N=20）和刷齿蜥蜴（N=72）的线虫。通过对cox2mtDNA基因和rDNAITS区域的序列分析，鉴定了168种线虫的子样本。物种A.typica（s.l.）（N=166），在分子上鉴定了Pseuderranovaceticola（N=1）和Anisakispaggiae（N=1）。基于两个基因的A.typica（s.l.）序列的系统发育分析，表明存在两个不同的系统发育谱系，形成两个支持良好的进化枝。第一个进化枝包括12个A型标本，包括来自其类型地区（大西洋中部）的个体。第二进化枝包括154个标本，与从GenBank检索的参考序列聚类，包括一个明显未描述的分类单元，即，Anisakissp.1，和A.typicavar。印度尼西亚。两个相互的单系进化枝密切相关，并对应于A.typica（s.l.）中的两个不同的姐妹物种，目前表示为A.typicasp.A和A.typicasp.B.两个和四个固定的替代核苷酸取代（SNP），即，诊断位置,在两个分类群之间，分别,在mtDNAcox2和rDNA的ITS区域发现。基因数据,以及它们在符号中的出现，加强了实际标本代表两个不同基因库的假设。两个A.typicasp.的发生。A和A.typicasp.在刚检查过的麻风病菌和S.undosquamis的肌肉组织中，表明这两个物种都可以在体内迁移到肉中。尽管A.typicas.l.的人畜共患潜力仍不清楚，这些寄生虫在肌肉组织中的存在，鱼的可食用部分，引起消费者对健康的担忧。
