الفهرس | Only 14 pages are availabe for public view |
Abstract Fish-borne trematodes (FBT) are extremely important zoonotically and can infect humans via the consumption of poorly cooked fish containing active metacercariae. In this study, samples of wild-caught and farmed Nile tilapia (Oreochromis niloticus) collected from Giza and Fayoum, respectively were investigated for the occurrence of FBT. The investigated O. niloticus were found to be infected with different encysted metacercaria (EMC) that were morphologically categorized at the genus level to Prohemistomum species, Haplorchis species, Clinostomum complanatum, C. phalacrocoracis and Euclinostomum heterostomum respectively in Giza and to Pygidiopsis species only in Fayoum. The mean prevalence of EMC of Prohemistomum sp., Haplorchis sp., Pygidiopsis sp., C. complanatum, C. phalacrocoracis and Euclinostomum heterostomum in both Governorates in (mean ± SD) were 81.89 ± 6.48, 18.03 ± 2.69, 34.64 ± 3.42, 35.94 ± 2.24, 60.93 ± 6.70 and 15.90 ± 5.17 respectively. Also the study provide the first molecular differentiation between Clinostomum sp., (C.complanatum and C.phalacrocoracis) and Euclinostomum sp. (E.heterostomum) in Egypt by sequencing their rDNA ITS and mtDNA COI and deposited their sequences in the GenBank. The accession numbers of the sequences of mtDNA COI genes of C.complanatum and C.phalacrocoracis and E.heterostomum were MT140101.1, MT140102.1 and MW193532.1, respectively. Moreover, the accession numbers of rDNA ITS genes were MT133890.1 and MT158303.1 for C.complanatum and C.phalacrocoracis, respectively. Experimental infection of domestic pigeons (Columba livia domestica) as a definitive host with Prohemistomum sp., Haplorchis sp., and Pygidiopsis sp. EMC confirmed the successful development of three types of adult digenetic trematodes in their small intestine, which could be identified as P. vivax, H. pumilio, and P. genata. Furthermore, this study presents the first molecular characterization of adult Heterophyidae, namely, P. genata and H. pumilio in Egypt by sequencing of their rDNA-ITS2 genes and deposited in the GenBank under the accession numbers MT672308.1 and MT707975.1, respectively. In addition, subsequent phylogenetic analysis of Clinostomum sp., Euclinostomum EMC and the recovered Heterophuidae flukes and the comparison with other trematode genes in GenBank. In the future, the molecular and the bioinformatics aspects based on genetic variations will lead to explore the untouched areas of trematodes. The histological findings of the infected tissues with the obtained EMC were also reported. |