DNA barcode identification of a tropical liver fluke (Fasciola gigantica) in cattle from Oyo, southwestern Nigeria

Abstract Background Fascioliasis is a major parasite illness that affects ruminants, both domesticated and free, and has an impact on public health and animals’ productivity. The genetic diversity of Fasciola species in cattle from Oyo, Oyo State, Nigeria is yet not well understood. In this study, the genetic diversity of Fasciola gigantica in slaughtered cattle in Oyo was examined using a molecular-based approach targeting the mitochondrial cytochrome C oxidase subunit I (COI) gene region. Results One hundred flukes were gathered from slaughtered cattle, and their COI gene sequences were analyzed using maximum likelihood methods. The results of phylogenetic analysis showed genetic similarities between Nigerian F. gigantica and isolates from Algeria, Egypt, Iran, Sudan, China, Japan and Nigeria. The predominant DNA substitution was the A to T transversion, while the least common substitution was the G to A transition. Conclusion Our results show how useful the COI gene region is for examining intraspecific differences between F. gigantica isolates. The genetic similarity observed among the sampled F. gigantica populations suggests the value of mitochondrial DNA sequences as a marker for the accurate identification and characterization of Fasciola species across different ruminants.