Genetic characterization of Trichomonas gallinae (Rivolta, 1878) in companion birds in Japan and the genotypical relationship in the Asia region.

BACKGROUND/PURPOSE: Avian trichomonosis is a parasitic infection that affects a wide range of avian species, including free-ranging and pet birds worldwide, and Trichomonas gallinae has been considered as the only causative agent for decades. The sequence of the 5.8S ribosomal RNA with internal transcribed spacer (ITS) regions was widely used for identifying genotypes and determining inter-specific and intra-specific diversity. Moreover, the sequence of Fe-hydrogenase (FeHyd) was proposed as the second genetic marker for providing improved resolution of strain subtyping discrimination. Though the correlation between genetic variability and strain virulence is controversial, FeHyd analyses seemed to be useful to investigate the host or geographic origin of isolates. This study aimed to investigate the genetic characteristics of avian Trichomonas spp. METHODS: Forty-seven oral swabs and crop lavage fluids were collected from 9 avian genera, which were diagnosed as Trichomonas-positive by microscopy in animal hospitals in Japan, were analyzed. RESULTS: Genetic analysis of clonal isolates revealed the prevalence of the single genotype, ITS-OBT-Tg-1, by ITS region analysis, while two different subtypes, A2 and novel A3, were suggested by FeHyd gene analysis among Japanese companion birds. Phylogenetic analyses of available ITS sequences obtained from the Asia region (China, Iran, Iraq, and Saudi Arabia) were also preformed, revealing endemic ITS-OBT-Tg-1, ITS-OBT-Tg-2, ITS-OBT-Ttl-1, genotype III, and Saudi Arabia's unique lineages. Furthermore, ITS-OBT-Tg-2 predominance in these countries indicates different strains origination from Japan. CONCLUSION: This is the first report of the genetic characterization of T. gallinae in Japan with discovery of novel subtype A3.

Resurrection of the genus Eumonospora (Apicomplexa: Sarcocystidae) for Caryospora species without Stieda body.

The coccidian genus Eumonospora Allen, 1933 is re-established. Despite morphological features and host preference among species, coccidian with octasporozoic and monosporocystic oocysts are traditionally consider to belonging in the genus Caryospora Léger, 1904 (Apicomplexa: Eimeriidae). Recently, the genus Avispora Schuster et al., 2016 was proposed for above caryosporoids parasitizing birds based on combined morphological and phylogenetic analyses. However, diagnostic morphological characters of the genus Avispora, the absence of Stieda and substieda bodies, has already been mentioned in the description of the genus Eumonospora Allen, 1933 (Apicomplexa: Sarcocystidae), and thus Avispora is considered to be a junior synonym of Eumonospora. In this study, caryosporoid coccidians were detected from five owl species; Bubo scandiacus, Ptilopsis leucotis, Athene noctua, Strix nebulosa, and Pulsatrix perspicillata (Strigiformes: Strigidae) and identified as Avispora henryae (Yakimoff & Matikaschwaili, 1932) described from Bubo bubo (Strigiformes: Strigidae). Eumonospora henryae (Yakimoff & Matikaschwili, 1932) comb. nov. is redescribed for this species based not only on morphological features but also on phylogenetical analyses. The key of the genus Eumonospora and a list to the species known at present are also provided.