Molecular Characterization of Liver Fluke Isolated from Sheep, Goat and Cattle in Sulaymaniyah, Iraq

Abstract

Background: We aimed to determine species of liver fluke that predominately cause fascioliasis in sheep, goats, and cattle in the Sulaymaniyah Province, Iraq using the molecular technique of DNA sequencing and restriction fragment length polymorphism (RFLP).
 Methods: The samples were collected from November 2021 to May 2022. The flukes were collected from infected livers of livestock at the slaughterhouse of Sulaymaniyah Governorate, Iraq. A total of 205 flukes were collected from 56 hosts, cattle (n=22), sheep (n=28), and goats (n=6). The specific primers for FCOX1 and 28S rDNA gene amplification were used. The PCR products were subjected to restriction fragment polymorphism (RFLP) assay using Hpy188III and Dra II restriction enzymes, besides DNA sequencing.
 Results: The results showed the genetic polymorphisms among the flukes. Three patterns of RFLP were observed Fasciola hepatica, F. gigantica, and F. intermediate, where 28 of them displayed F. hepatica (sheep, n=14, goat, n=3 and cattle, n= 11), whereas 24 samples displayed the F. gigantica (sheep, n=12, goat, n=3 and cattle, n= 9), and only four samples belonged to F. intermediate (sheep n=3 and cattle, n=1). In addition, the result of the ribosomal DNA (28S rDNA) sequencing confirmed that the isolated flukes belonged to F. hepatica, F. gigantica and F. intermediate.
 Conclusion: All three main species are present in the study area and F. hepatica predominated among the animal species in this area also, our results concluded that PCR-RFLP is a rapid and reliable method for liver fluke species identification.