THEILERIA-SERGENTI AND T-BUFFELI - POLYMERASE CHAIN REACTION-BASED MARKER SYSTEM FOR DIFFERENTIATING THE PARASITE SPECIES FROM INFECTED CATTLE BLOOD AND INFECTED TICK SALIVARY-GLAND

Benign Theileria species in cattle, Theileria sergenti and T. buffeli, are morphologically indistinguishable. The polymerase chain reaction (PCR) was used to amplify the genes encoding the 33- and 34-kDa major piroplasm antigens (p33/34) of T. sergenti and T. buffeli from cattle blood infected with these parasites and tick salivary gland infected w ith T. sergenti. Following amplification, the p33 gene from T. sergent i and the p34 gene from T. buffeli were clearly differentiated using t he restriction enzyme sites that were not shared between them. The oli gonucleotide primer set, designed from the p33/34 genes, was specific for these Theileria species, since no amplification was detected with DNA from Babesia ovata, B. bovis, Anaplasma marginale, A. centrale, Ep erythrozoon wenyoni, bovine white blood cells, and uninfected tick sal ivary glands. One tenth vol of the template prepared from either 25 mu l of blood with 0.5% parasitemia or individual tick salivary glands w ith six infected acini allowed sufficient amplification for differenti ation of the two parasite species by restriction enzyme digestion. In addition, this system could be used to demonstrate the simultaneous, e xperimentally induced infection of cattle with T. sergenti and T. buff eli. The PCR-based marker system therefore provides a means to differe ntiate T. sergenti from T. buffeli in infected cattle blood and infect ed tick salivary glands. This system may also be useful for the charac terization of other benign Theileria species in cattle. (C) 1995 Acade mic Press, Inc.