Introduction: Coxiella burnetii is an obligatory intracellular bacterial pathogen causing the zoonotic disease Q fever. The most common reservoirs of C. burnetii are wild mammals, birds and ticks. Pregnant domestic ruminants infected with this bacterium are also a major source of human infection.
Material and methods: The serological prevalence of C. burnetii in goats and sheep diagnosed with adverse pregnancy outcomes was assessed by undertaking a survey on 800 dairy goats and 800 dairy ewes reared in four different regions of Greece (Macedonia, Thrace, Thessaly, and Peloponnese). A stratified sampling was carried out, taking also as a criterion the age of the animals. Serum antibodies were analyzed by a commercial ELISA according to the manufacturer's recommendations.
Results: Generally, there was a statistically significantly higher serological prevalence of C. burnetii (14.4%) in goats compared to sheep (8%). Serological prevalence was higher in adults (15.5% in goats and 8.5% in sheep) compared to yearlings (7.4% in goats and 4.6% in sheep). The prevalence increased significantly with age only in goats. Finally, all animals reared in Peloponnese had a prevalence significantly higher (21% in goats and 18% in sheep) than animals reared in the other three regions.
Conclusions: To the best of the authors' knowledge, this is the first report that associates C. burnetii with reproductive disturbances of domestic ruminants in Greece. However, considering the importance of coxiellosis for public health, further investigations are required on its epidemiology regarding abortion, premature delivery, stillbirth and weak offspring in small ruminants, as well as in other domestic and wild animal species.
Keywords: Coxiella burnetii; dairy goats; dairy sheep; reproduction.