Objectives: The most common parasites responsible for fascioliasis are F. hepatica and
F. gigantica. Fascioliasis is an important problem in terms of health and economics. The western
part of Iran is one of the major hubs of animal husbandry and the prevalence of fascioliasis is
high. The aim of the current study was to determine the Fasciola spp. present in the western part
of Iran. In the present study, 45 samples were collected from slaughterhouses in three provinces in
the western part of Iran, including Ilam, Lorestan and Kermanshah.
Methods: The flukes were detected using morphological methods and the DNA of all samples was
extracted. The ribosomal internal transcribed spacer (ITS1) was identified by PCR and PCR-RFLP
techniques using the Rsa1 restriction enzyme. Then, 15% of the samples were sequenced.
Results: Based on their ITS1 sequence, all samples showed 700 bp bands. The results of sequencing
showed a similarity of 99% to 100% across samples. Using the Rsa1 restriction enzyme, all
samples produced three distinct bands (60 bp, 100 bp, and 360 bp). These results demonstrated
that the most common fasciola in the western part of Iran in sheep and cattle is F. hepatica.
Conclusion: The results of the present study showed that only the species F. hepatica is parasitizing
livestock in the western part of Iran. Further studies using new molecular markers for more
accurate identification of fasciola-causing species will be useful in the control and prevention of