Molecular characterization of Plasmodium juxtanucleare in Burmese red junglefowls (Gallus gallus spadiceus) in Thailand

摘要

Plasmodium gallinaceum and Plasmodium juxtanucleare are the most common species of Plasmodium causing avian malaria in domestic and wild chickens. In Thailand, P. gallinaceum infection in poultry has been reported since 1996, but P. juxtanucleare infection has never been reported. The objective of this study was to identify and characterize the Plasmodium species infecting Burmese red junglefowls (Gallus gallus spadiceus) in Thailand using molecular techniques. Seventeen Burmese red junglefowls froma farm in western Thailand were suspected of being infected with blood parasite. Blood samples of all seventeen Burmese red junglefowls were collected and examined. Microscopic examination revealed the presence of Plasmodium trophozoites in 5 out of 17 samples. In comparison, nested PCR detected 12 samples to be positive for Plasmodium spp. Molecular characterization, based on partial sequence of mitochondrial cytochrome b gene, revealed 7 PCR-positive samples as P. juxtanucleare. Nucleotide sequence comparison and phylogenetic analyses grouped these 7 P. juxtanucleare into 2 distinct groups. The first group was identical to P. juxtanucleare previously reported from Brazil, Malaysia and Taiwan, whereas the second group was identical to P. juxtanuclearefrom Japan. This is the first report on molecular confirmation and characterization of P. juxtanucleare in Burmese red junglefowls in Thailand.