RAPD analysis and sequencing of ITS1/5.8S rRNA/ITS2 and Fe-hydrogenase as tools for genetic classification of potentially pathogenic isolates of Trichomonas gallinae.

Abstract

Trichomonas gallinae is a worldwide parasite that causes oropharyngeal avian trichomonosis. During eight years, 60 axenic isolates were obtained from different bird species and characterized by three molecular methods: RAPD analysis and PCR-sequencing of ITS1/5.8S rRNA/ITS2 fragment and Fe-hydrogenase gene. We have found two genotypes of ITS1/5.8S rRNA/ITS2 widely distributed among bird populations, a new variant and also two sequences with mixed pattern. Genotype ITS-OBT-Tg-1 was associated with the presence of gross lesions in birds. We have found eight genotypes of the Fe-hydrogenase (A1, A2, C2, C2.1, C4, C5, C6 and C7), three of them are new reports (C5, C6 and C7), and also three sequences with mixed pattern. Subtype A1 of the Fe-hydrogenase was also related with the presence of lesions. RAPD analyses included most of the strains isolated from animals with lesions in one of the sub-clusters. Potentially pathogenic isolates of T. gallinae obtained in this study fulfill the following criteria with one exception: isolated from lesions+ITS-OBT-Tg-1 genotype+FeHyd A1+RAPD sub-cluster I2.