Molecular and Morphometrical Characterization of Fasciola Species Isolated from Domestic Ruminants in Ardabil Province, Northwestern Iran

Background: We aimed to describe morphological and morphometrical characteristics of Fasciola spp. in livestock from Ardabil Province, Northwest Iran. Methods: Forty adult flukes were collected from different definitive hosts (cattle and sheep). Previously specimens were identified as F. hepatica or F. gigantica based on PCR-RFLP of the ITS-1 region with RsaI enzyme. We identified Fasciola spp. based on morphological and metric assessment of external features of fresh adults, morphological and metric assessment of internal anatomy of stained mounted worms. Statistical analysis was conducted using the Student's t-test implemented in SPSS 15.0 (SPSS, Chicago, Illinois). Then the morphometric criteria of Fasciola samples were compared with PCR-RFLP data. The results of PCR-RFLP were confirmed by COI gene sequence. Results: The differences between the body length, area of the body, peripheral of the body, succer area, cone length, cone width, in two species were significant (p < 0.05). Based on Morphological characterizations, 6 specimens had the intermediate morphological features and 19 and 15 specimens had morphological features of F. hepatica and F. gigantica, respectively. In contrast, RFLP results showed, F. hepatica was present in 20 of the isolates, and F. gigantica in 20 isolates. No hybrid forms were detected. Conclusion: PCR-RFLP method can be used for differentiation of Fasciola species, which is more reliable method than morphology. Using morphology methods, merely, is not efficient for determination of genetic diversity.