丹顶鹤源棘口吸虫的形态及分子生物学鉴定

Morphological and Molecular Biological Identiflcation of Echinostoma from Red-crowned Crane

笔者从急性死亡的丹顶鹤胃肠道内采集寄生虫体,根据寄生虫形态结构、寄生部位、虫卵特征,采用分子生物学等方法对虫体进行鉴定。虫卵呈椭圆形,淡黄色,前端有卵盖。虫体长13〜20 mm、宽1〜2 mm,体表有小棘,口吸盘较小,位于虫体顶端,周围有头冠。腹吸盘略大,口吸盘与腹吸盘距离较近,约为虫体长度的1/3。卵黄腺发达,分布于虫体中后部两侧,子宫、卵巢在腹吸盘下方。采用PCR方法扩增虫体ITS序列,并登陆NCBI进行Blast分析,结果该虫体的ITS1序列与棘口吸虫属的凯氏棘口吸虫株ECPC2012-1(登录号为KF425322)的核苷酸序列相似性最高,为91%;ITS2序列与登录号为JF412727的棘口吸虫属le分离株核苷酸序列相似性最高,为95%。从Genbank下载相关吸虫序列与分离株进行苷酸序列相似性及基因进化树分析,显示与其他多种吸虫的核苷酸序列相似性在88.3%〜89.3%之间。

The parasites were collected from the gastrointestinal tract of the acutely dead red-crowned crane,and the parasites were identified based on morphology,parasitic site,egg characteristics,molecular biology and other methods.The results showed that the eggs were oval,pale yellow,and the anterior segment had egg covers.The body length of the Parasite is 13-20 mmxl-2 mm.There are small spines on the body surface and the oral sucker is small.It is located at the top of the body and has a crown around it.The ventral sucker is larger and closer to the the oral sucker,about one third of the length of the body.The vitelline glands is developed and distributed on both sides of the middle and back of the body.The uterus and ovary are under the ventral sucker.PCR method was used to amplify the ITS sequence of the parasites,and analyzed using blast in NCBI.The result showed that the ITS1 sequence had the highest similarity(91%)with the Paragonimus echinoides strain ECPC2012-1(accession number KF425322).and the ITS2 sequence had the highest similarity(95%)with the isolate of Lepidospora le(accession number JF412727).Download the related trematode sequences from Genbank,Analysis of genetic evolution it shows that the nucleotide sequence similarity with other trematodes is between 88.3%and 89.3%.