Molecular evolution of Theileria parasites in Southern Asia

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Bovine piropurasmosis due to Theileria sergenti is a major cause of economic loss in grazing cattle in Japan. T. sergentii / buffeli / orientalis grop is referred to as bengin theileria parasites of cattle and is known to be distributed all over the world. Previously, we developed the allele-specific polymerase chain reaction (PCR) which specifically amplifies lach allelic from using 3 sets of olgonucleotide primers designed from nucleotide sequences of major Immunodominant primers designed from nucleotide sequences of major Immunodominant piroplasm surface protein (p32) genes of two T. sergenti stocks, Ikeda (1) and Chitose c and one t, buffeli (B) stok, Warwick, and appled the method to the field survey of benign theileria parasites in southern asian countries.During 2 years, we have collected blood samples from the following countries : Korea (Cheju island), Thailand, Cambodia, India, Paklstan, Vietnam and China. Parasites DNA was extracted and the DNA was analyzed by using allele-specific PCR. In Korea (Cheju island), all the isolates contained I type parasites as well as C type parasites. However In Thailand and Cambodia, Major parasites distributed there countries were Thai type parasites, different from T. sergentii /buffeli / orientalis. C type parasites and T, buffeli type parasites were also isolated from Thailand and Cambodia. In India and Pakistan, major theileria parasites are known as T. annulata. We expected to isolate benign theileria parasites, however, we could not isolate benign theileria parasites. The present data showed that benign theileria parasites in east and Southern asian countries were mixed parasites populations.