Background: Theileria & Babesia species are tick-borne haemoprotozoan parasites of vertebrates that had a chief force on domestic animals production, mainly cattle and small ruminants in tropical and subtropical areas. The diseases are still closely related to huge economic losses particularly in developing countries and Iraq; therefore, the aim of study is to determine tick-borne haemoprotozoan parasites infection in cattle of various ages based on ME and genetic methods from different regions in Al-najaf province of Iraq. Materials & methods: A total of 150 blood samples were collected from February 2015 to February in 2016. Prevalence of infection was determined by Stained blood smears were microscopically examined for the presence of Theileria and Babesia organisms, and PCR was used for subsequent molecular specification hypervariable V4 region of the 18S ribosomal RNA (rRNA) gene was amplified with a set of primers for members of the genera Theileria and Babesia. Results: PCR identified infection in 69.3 % (104/150) of the samples. There was a significant difference (P ≤ 0.05) in the infection rate according to the tests.The Prevalence identified in cattle Theileria prevalence was 61.9% (78/126), and prevalence of Babesia was 20.6% (26/126) & the last one was less frequently detected. The results also suggest that the demographical picture of samples according to location & age, the Present results showed that the highest ratio in Al- meshkab (south of Al-najaf) was (27.8%). While the results showed that the age group between 2 to 3 years was the most vulnerable age group to piroplasms was recorded 58(46%), followed by age group (1- 2) years 42 (33.3%). Conclusions: the cattle in Al-najaf province were bearing the infection of piroplasmosis and recommended that the epidemiological condition calling for using more than two tests like microscopic examinations & PCR or ME & serological methods together.
