Detection and differentiation of Theileria luwenshuni and T. uilenbergi infection in small ruminants by PCR.

Theileria luwenshuni and T. uilenbergi are newly identified Theileria species highly pathogenic for sheep and goats in China. As they are morphologically indistinguishable and poorly characterized, there is no easily applicable method available to differentiate between these species. In the present study, PCR assays are described for the differentiation and detection of T. luwenshuni and T. uilenbergi using species-specific primers, which were designed based on the hypervariable region of the small subunit ribosomal RNA gene sequences. By testing 100 field blood samples of sheep collected from five geographically different regions where the Theileria species were described to be prevalent, the PCR assays not only detected infected samples but also identified mixed infection. This suggests that these PCR assays are useful tools for the detection of and differentiation between T. luwenshuni and T. uilenbergi.