Department of Medical Parasitology and Mycology, School of Medicine, Zanjan University of Medical Sciences, Zanjan, Iran.
Department of Medical Parasitology and Mycology, Urmia University of Medical Sciences, Urmia, Iran.
Vet Med Sci. 2024 Nov;10(6):e70097. doi: 10.1002/vms3.70097.
Liver flukes from the genus Fasciola are the causative agents for human and livestock fascioliasis. Accurate identification of Fasciola spp. is essential to understanding the epidemiology of fascioliasis. This study aimed to determine the morphometric and molecular characterization of Fasciola spp. in livestock from Northwestern provinces of Iran.
Five hundred adult Fasciola flukes were obtained from different definitive hosts (cattle, sheep, goats, and buffaloes) in four local abattoirs in the northwestern provinces of Iran (West-Azerbaijan, East-Azerbaijan, Ardabil, and Zanjan) from September 2021 to August 2022. All samples were examined by morphometric criteria; then, 49 samples were identified using PCR-RFLP based on ITS1 region and 23 sequence of isolates analyzed by cox1 marker. PCR-RFLP methods compared morphometric results, and cox1 gene sequences were used to confirm PCR-RFLP results and phylogenetic analysis.
The differences between the body length, body width, cephalic cone length, cephalic cone width, body area, and distance between the ventral sucker and posterior end of the body in two species were significant (p < 0.05). Based on the morphometric criteria, 139 samples (27.8%) were identified as Fasciola gigantica and 361 (72.2%) as Fasciola hepatica. Similarly, PCR-RFLP analysis of ITS1 region confirmed morphometric results. No hybrid forms of Fasciola were detected. Partial sequences of cox1 showed 13 variable sites with eight haplotypes in F. hepatica and 12 variable sites with five haplotypes in F. gigantica.
Based on the results of this study, the PCR-RFLP method can be used to confirm the morphological method of Fasciola species, but it is insufficient to study their genetic diversity. Also, sequences of cox1 results of the present study showed that F. hepatica and F. gigantica species in the Northern provinces of Iran have different genetic structures and haplotypes.
肝片吸虫属的肝吸虫是人类和家畜片形吸虫病的病原体。准确鉴定肝吸虫属对了解片形吸虫病的流行病学至关重要。本研究旨在确定伊朗西北部省份家畜中肝吸虫属的形态特征和分子特征。
2021 年 9 月至 2022 年 8 月，从伊朗西北部四个省（西阿塞拜疆、东阿塞拜疆、阿尔达比勒和赞詹）的四个当地屠宰场的不同终末宿主（牛、羊、山羊和水牛）中获得了 500 只成年肝吸虫。所有样本均通过形态学标准进行检查；然后，根据 ITS1 区和分离株的 23 个 cox1 标记，使用 PCR-RFLP 对 49 个样本进行鉴定。PCR-RFLP 方法比较了形态学结果，cox1 基因序列用于确认 PCR-RFLP 结果和系统发育分析。
两种肝吸虫在体长、体宽、头锥长、头锥宽、体面积和腹吸盘与体后端的距离方面存在显著差异（p<0.05）。根据形态学标准，139 个样本（27.8%）鉴定为巨型片形吸虫，361 个样本（72.2%）鉴定为肝片吸虫。同样，ITS1 区的 PCR-RFLP 分析证实了形态学结果。未检测到 Fasciola 的杂交种。cox1 的部分序列显示，在 F. hepatica 中有 13 个可变位点和 8 个单倍型，在 F. gigantica 中有 12 个可变位点和 5 个单倍型。
根据本研究结果，PCR-RFLP 方法可用于确认肝吸虫属的形态学方法，但不足以研究其遗传多样性。此外，本研究 cox1 序列结果表明，伊朗北部省份的 F. hepatica 和 F. gigantica 种具有不同的遗传结构和单倍型。
