Developmental and morphological characteristics of 3 isolates of Taenia taeniaeformis isolated from Clethrionomys rufocanus bedfordiae in Abuta (70 km southwest of Sapporo), Japan (isolate ACR), and from Rattus norvegicus in Sapporo, Japan (isolate SRN) and Kuala Lumpur, Malaysia (isolate KRN) were compared. Eggs of 3 isolates were administered to several species of rodents. Isolate ACR infected C. rufocanus bedfordiae, Apodemus speciosus, and Apodemus argenteus, but not rats or mice, whereas isolate SRN and isolate KRN were infective to rats, mice, A. speciosus, and A. argenteus, but not to C. rufocanus bedfordiae. The increase in cyst size of isolate ACR continued during the experimental period, whereas that of the other 2 isolates had ceased growing after 30 days postinfection. However, significant differences were observed in the length of the small rostellar hooks, number and distribution of testes, and the length of the cirrus sac between isolate ACR and the other 2 isolates. Thus it is suggested that isolate ACR is a distinct strain or even a new species.
Taenia taeniaeformis were isolated from Norway rats captured at Sapporo (SRN isolate) and Kuala Lumpur, Malaysia (KRN) and from Bedford's gray red-backed voles at Toubetsu (TCR) and Abuta (ACR). SRN, KRN and TCR isolates showed similar degree of infectivity to various rodents in which cysticerci with hooks were obtained in laboratory rats, white tuberous lesions in mice and no cysts or lesions in Mongolian gerbils and voles. Contrary to this, inoculation with ACR isolate eggs resulted in strobilocerci formation in the liver of voles, but no cysts were observed in rats, mice or gerbils. This host specificity of ACR isolate to voles suggests that it might be a new species of Taenia.
Village chicken production, a traditional, small-scale, and extensive backyard poultry industry, has been profitable for local farmers in Myanmar. However, there is scanty information available concerning the infection of these chickens with avian pathogens, including haemoprotozoan parasites. In the present study, we provide the first report of microscopic detection and molecular identification of Leucocytozoon and Plasmodium parasites from seven different areas of Myanmar. Leucocytozoon gametocytes were detected in 17.6% (81/461) of the blood smears from village chickens. The nested polymerase chain reaction (PCR) for targeting Leucocytozoon mitochondrial cytochrome b (cyt b) genes had a 17.6% positive rate. Although the positive rate of nested PCR targeting Plasmodium/Haemoproteus cyt b was 34.3%, the PCR protocol was observed to possibly amplify DNA of a certain species of Leucocytozoon. There were no obvious clinical signs in the infected birds. Statistical analysis of the microscopic detection and PCR detection rates using the age and sex of birds as internal factors revealed that the statistical significances differed according to the study area. The sequencing of 32 PCR products obtained from each study area revealed infection by Leucocytozoon caulleryi in three birds, Leucocytozoon sabrazesi in two birds, Leucocytozoon schoutedeni in two birds, Leucocytozoon sp. in eighteen birds, and Plasmodium juxtanucleare in seven birds; however, Haemoproteus infection was not detected. While L. sabrazesi was detected in chickens from the central region of Myanmar, the other haemosporidians were detected in those from different areas. In the haplotype analysis, we detected 17 haemosporidian cyt b haplotypes, including two for L. caulleryi, one for L. sabrazesi, two for L. schoutedeni, nine for Leucocytozoon sp., and three for P. juxtanucleare. Phylogenetic analysis of the cyt b haplotypes revealed a considerably close genetic relationship among chicken haemosporidians detected in Myanmar, Thailand, and Malaysia. These results indicate that well-recognized widespread species of chicken Leucocytozoon and Plasmodium are distributed nationwide in Myanmar, providing new insights into the ecosystem and control strategies of haemosporidian parasites in domesticated chickens in Myanmar.