Identification of Dibothriocephalus nihonkaiensis plerocercoids from the autumn chum salmon Oncorhynchus keta of the Amur River basin by molecular datas

The purpose of the research is determination of the species belonging to the Dibothriocephalus spp. plerocercoids from the autumn chum salmon Oncorhynchus keta of the Amur River basin based on the analysis of a gene fragment of the first cytochrome c oxidase (COX1) subunit of mitochondrial DNA. Materials and methods . A total number of 61 salmon specimens (Oncorhynchus keta) caught in the Amur River and its tributaries were examined with helminthological analysis. DNA of Dibothriocephalus spp. was isolated from plerocercoids and afterwards amplified to detect mitochondrial COX1 partial gene of the D. nihonkaiensis. Products of amplification were sequenced via Sanger sequencing. Obtained nucleotide sequences were analyzed in BLAST. Results and discussion . Type F plerocercoids were detected in nine specimens of O. keta. The sequenced fragments showed 99.31–100 % similarity with GenBank reference sequences of D. nihonkaiensis. The conducted research confirmed infestation with Dibothriocephalus nihonkaiensis (dyphyllobotriosis pathogen) of O. keta species caught in the Amur River in the territory of the Khabarovsk krai.