Molecular Identification of Trematode, Haplorchis taichui Cercariae (Trematoda: Heterophyidae) in Tarebia granifera Snail Using ITS2 Sequences

Abstract

Minute intestinal fluke, Haplorchis taichui, remain clinical importance, especially in the north-eastern and northern regions of Thailand. For obtaining an effective epidemiological control program, a sensitive, accurate, specific detection are required. Sequences of Internal transcribed Spacer subunit 2 were performed to identify cercarial trematodes in snail intermediate hosts.The results showed that phylogram depicting phylogenetic relationships was constructed based on combined sequence data of ITS2 and showed that, 2 distinct clusters were formed by first containing with the group of middle-larger sizes trematode while the remaining was minute size with all of them were belonged to family Heterophyidae. Within the minute size cluster, H.taichui and Pleurolophocercous cercaria were placed in the same branch which can confirm the identities of PC found in this study that they will be developed and identified to H. taichui. Additionally, results obtained in this study were effective to determine the presence of parasites in snail intermediate hosts that can be use for epidemiological monitoring, preventing management and control program.