Objective: Q fever is a zoonotic disease caused by the rickettsial organism Coxiella burnetii, the objective of this study was to determine the prevalence rate of C. burnetii in bulk milk samples from dairy cow herds in Yazd provinces, Iran. Methods: In the present study, 100 bulk milk samples from 10 dairy cow herds were tested for C. burnetii using a nested PCR assay. The animals which their milk samples collected for this study were clinically healthy. In total, 5 of 100 (5.0%) cow milk samples were positive. Results: The results of this study indicate those clinically healthy dairy cows are important sources of C. burnetii infection in Iran
