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Background and Objective: Identification of Fasciola species is important. Fascioliasis is one of the important diseases in animals and humans caused by genus Fasciola. This study was done to determine the identification of Fasciola species with RFLP-PCR in animal liver in Gorgan City, northern Iran.
Methods: In this descriptive study, worms were obtained from the livers of infected sheep and cattle in Gorgan slaughterhouse in northern Iran. DNA of worms was extracted with phenol- chloroform method. Fragment of ITS-1 genome was amplified and TasI enzyme was utilized for amplified fragments then 8 samples were sequenced.
Results: A total of 49 Fasciola worms were isolated from infected cattle and sheep. The PCR products of all specimens were affected by the TasI enzyme, and F.hepatica species showed two fragments and F.gigantica species indicated three fragments. The enzyme in F.hepatica species showed a fragment of 151 bp and a fragment of 312, but in the F.gigantica, three fragments were 151, 93 and 219 bp. 36 (73.46%) worms were identified as Fasciola gigantica and 13 (26.53%) worms were identified as Fasciola hepatica. Out of the six infected sheep liver, 22 were isolated from the Fasciola worms, 13 (59.1%) of which were F.hepatica and 9 (40.9%) of them were F.gigantica. Out of the six infected cattle liver, 27 Fasciola worms were identified, all of which were identified as Fasciola gigantica (100%).
Conclusion: This study showed that Fasciola gigantica is the dominant species in infected livers of the cattle in Gorgan city.