Akhlaghi Elham, Mohammadi Mohammad Ali, Ziaali Naser, Baneshi Mohammad Reza, Nasibi Saeid, Kamyabi Hossein, Rostami Sima, Harandi Majid Fasihi
Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, İran.
Department of Parasitology, Kerman University of Medical Sciences, Kerman, İran.
Turkiye Parazitol Derg. 2017 Dec;41(4):192-197. doi: 10.5152/tpd.2017.5214.
The purpose of the present study was morphometric and molecular characterization of Fasciola isolates from ruminants in Iran.
Flukes were collected from the livers of 54 naturally infected sheep and cattle. The proportion of body length to width (L/W) of each fresh fluke was measured using a digital caliper. We employed receiver operating characteristic (ROC) curve analysis to explore the reliability of L/W for differentiating the two species. Polymerase chain reaction (PCR)-sequencing was performed on ribosomal Internal Transcribed Spacers (ITS) and mitochondrial cytochrome c oxidase subunit 1 (cox1) genes. The sequences were then analyzed and phylogenetic relationships were investigated.
Forty-eight out of 54 isolates (88.9%) were identified as F. hepatica and four isolates (7.4%) as F. gigantica. All the sheep isolates were F. hepatica, while 4 out of 10 cattle were infected with F. gigantica. The morphometric study revealed an L/W ratio of 1.2 to 6.5 in Fasciola isolates with significantly higher L/W ratio in F. gigantica (p<0.00). According to the ROC curve analysis, the L/W value of 3.55 was regarded as the critical value to discriminate between the two species.
Findings of the present study indicate the presence of both Fasciola species in southeastern Iran. The phylogenetic analysis revealed two different clades representing F. hepatica and F. gigantica. The two isolates in this study were described as Fasciola sp. The mitochondrial DNA of these isolates were similar to F. hepatica, while their ITS fragments were identical to F. gigantica.
本研究旨在对伊朗反刍动物体内的肝片吸虫分离株进行形态测量和分子特征分析。
从54只自然感染的绵羊和牛的肝脏中采集吸虫。使用数字卡尺测量每只新鲜吸虫的体长与体宽之比（L/W）。我们采用受试者工作特征（ROC）曲线分析来探讨L/W用于区分这两个物种的可靠性。对核糖体内部转录间隔区（ITS）和线粒体细胞色素c氧化酶亚基1（cox1）基因进行聚合酶链反应（PCR）测序。然后对序列进行分析并研究系统发育关系。
54个分离株中有48个（88.9%）被鉴定为肝片吸虫，4个分离株（7.4%）为巨片吸虫。所有绵羊分离株均为肝片吸虫，而10头牛中有4头感染了巨片吸虫。形态测量研究显示，肝片吸虫分离株的L/W比为1.2至6.5，巨片吸虫的L/W比显著更高（p<0.00）。根据ROC曲线分析，L/W值3.55被视为区分这两个物种的临界值。
本研究结果表明伊朗东南部存在这两种肝片吸虫。系统发育分析揭示了代表肝片吸虫和巨片吸虫的两个不同分支。本研究中的两个分离株被描述为肝片吸虫属未定种。这些分离株的线粒体DNA与肝片吸虫相似，而它们的ITS片段与巨片吸虫相同。
