A molecular survey was performed for identification Theileria spp in sheep and ticks during from 2010-2011 in Fasa and Kazeroun areas, Fars province, Iran. A total of 100 sheep from different flocks were clinically examined and blood samples with ixodid ticks collected. The prepared blood smears from capillary vein of ear were stained with giemsa methods and examined by using light microscope. The collected ticks were separated into tick pools with five ticks according to their species and sex. Then, the salivary glands were dissected out in ٠.٨۵% saline solution under stereomicroscope. The boold and tick salivary glands samples were examined by using semi-nested PCR. The Theileria spp infection was observed in 46% of blood smears, while 76 % of blood samples were positive by using semi-nested PCR. T. ovis, T. lestoquardi and mixed infection were detected in 43 (43%), 3 (3%) and 30 (30%) of positive samples, respectively. Any significant difference was not observed between the frequency of Theileria spp infection in sheep of Kazeroun and Fasa areas. In the present study, the most prevalent ticks were R. turanicus 48.8% and followed by H. a. anatolicum 42.2% and H. marginatum 8.8%. The results were shown that one pool belong to salivary glands of H. turanicus were infected with T. ovis. Based on the obtained results, it is concluded that T. ovis have high prevalence with compared to T. lestoquardi and also, R. turanicus could be the vectors T. ovis in this area

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