author(s)
K Sudhakar Goud and K Vijayakumar

abstract
Theileria orientalis is a tick-born haemoprotozoan parasite distributed throughout the world. It causes significant economic losses to livestock industry, because no commercially effective medicines or vaccines are currently available for its control. Among the different molecular markers are used to study and characterise this parasite, major piroplasm surface protein (MPSP) gene is most commonly used and reliable marker to characterise this parasite. We compared the efficiency of two primer sets for diagnosis of Theileria orientalis in 32 cattle blood samples that were showing clinical signs suggestive of theileriosis. Light microscopic examination revealed twenty two cattle were positive for theileriosis. In PCR we used two primer sets that amplify the 32kDa major piroplasm surface protein (MPSP) antigen gene of T. orientalis. Polymerase chain reaction (PCR) based methods showed higher sensitivity in identifying positive cases than detected by light microscopy. Primer set 1 identified 23 cattle as positive, whereas primer set 2 identified all the 32 cattle examined as positive for T. orientalis. Our preliminary analysis concludes that PCR based method was more efficient in detecting oriental theileriosis in cattle and primer set 2 is the first choice for epidemiological studies of T. orientalis.