RESUMO
Fasciolosis in livestock is a crucial concern in the globe, mainly due to its impact on human health. The aim of this study was to determine the rate of infection with Fasciola gigantica [Cobbold, 1855] larvae in the field-collected snails of Lymnaea auricularia [Linnaeus, 1785] from northwestern Iran using a molecular approach. A total of 6,759 pond snails were collected from 28 freshwater bodies in West Azarbaijan. PCR was performed to amplify a 618-bp fragment of the nu-clear 28 SrRNA gene of Fasciola. The PCR products were digested by AvaII re-striction enzyme to create restriction fragment length polymorphism [RFLP] pat-terns specific for the detection of F. gigantica. Of the total collected snails 496 [7.34%] were L. auricularia, among which 4.64% [23 out of 496] were infected with a Fasciola species according to the PCR analysis. Only 2.22% [11 out of 496] of the infected snails were from the mountainous areas. The highest Fasciola infection rate recorded in the snails of a single site was 1.81% [9 out of 496 snails]. Based on the RFLP pattern, F. gigantica accounted for 2.42% of the infection rates in the study sites. Application of PCR-RFLP was proven to be a useful approach for valid and robust detection of the infection with F. gigantica in its intermediate host snails. These findings may therefore be applicable for establishment of the control programs against dissemination of the infection in different regions