School of Life Sciences, East China Normal University, No. 3663 North Zhongshan road, Shanghai 200062, People's Republic of China.
Parasitol Res. 2012 Oct;111(4):1531-9. doi: 10.1007/s00436-012-2993-8. Epub 2012 Jun 29.
There are three Echinococcus species, Echinococcus granulosus, E. multilocularis, and E. shiquicus, which are distributed on the vast area of pastureland on the eastern Tibetan plateau in China. Tibetan foxes (Vulpes ferrilata) have been determined to be the main wild definitive host of E. multilocularis and E. shiquicus, but little information is available on the prevalence of these two parasites in Tibetan foxes. Consequently, the copro-prevalence of these parasites in foxes from the eastern Tibetan plateau was evaluated in this study. For each copro-DNA sample extracted from fox feces, a 133-bp segment of EgG1 Hae III was used to screen for infection with E. granulosus. Multiplex nested polymerase chain reaction (PCR) analysis was used to target an 874-bp segment of the mitochondrial COI gene to distinguish E. multilocularis and E. shiquicus. Among 184 fecal samples, 120 were from Tibetan foxes and six from red foxes (Vulpes vulpes). Of the fecal samples from Tibetan foxes, 74 (giving a copro-prevalence of 62%) showed the presence of Echinococcus spp.: 23 (19%) were found to contain E. multilocularis, 32 (27%) E. shiquicus, and 19 (16%) showed mixed infection with both E. multilocularis and E. shiquicus. Two fecal samples from red foxes were found to be infected with E. multilocularis. No fox feces were found to be infected with E. granulosus. Tests on zinc finger protein genes and a 105-bp fragment of the Sry gene found no significant difference in the prevalence of the two parasites between sexes. The efficiency of our multiplex nested PCR methods were compared with previous polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) methods and some problems associated with the copro-PCR were discussed.
在中国东部青藏高原广阔的牧场上分布着三种细粒棘球绦虫（Echinococcus granulosus）、多房棘球绦虫（E. multilocularis）和青海棘球绦虫（E. shiquicus）。藏狐（Vulpes ferrilata）被确定为多房棘球绦虫和青海棘球绦虫的主要野生终末宿主，但关于这两种寄生虫在藏狐中的流行情况知之甚少。因此，本研究评估了来自中国东部青藏高原的藏狐粪便中这些寄生虫的Coprevalence。从每只狐狸粪便提取的 copro-DNA 样本中，使用 133-bp 片段的 EgG1 Hae III 筛查感染细粒棘球绦虫的情况。多重巢式聚合酶链反应（PCR）分析使用线粒体 COI 基因的 874-bp 片段来区分多房棘球绦虫和青海棘球绦虫。在 184 个粪便样本中，有 120 个来自藏狐，6 个来自赤狐（Vulpes vulpes）。在来自藏狐的粪便样本中，有 74 个（感染率为 62%）显示出棘球绦虫属的存在：23 个（19%）含有多房棘球绦虫，32 个（27%）含有青海棘球绦虫，19 个（16%）同时感染多房棘球绦虫和青海棘球绦虫。两只赤狐的粪便样本被发现感染了多房棘球绦虫。没有狐狸的粪便样本被发现感染细粒棘球绦虫。锌指蛋白基因和 Sry 基因的 105-bp 片段检测结果表明，两种寄生虫在性别之间的流行率没有显著差异。我们的多重巢式 PCR 方法的效率与以前基于聚合酶链反应的限制性片段长度多态性（PCR-RFLP）方法进行了比较，并讨论了与 copro-PCR 相关的一些问题。
