Coxiella burnetii is an obligate intracellular agent that causes Q fever in humans and animals. The most important reservoirs of C. burnetii in nature are small wild rodents, but infection was also demonstrated in other animals, including ruminants. Samples of blood were obtained from 4 mouflons, 60 fallow deer, 9 Cameroun goats, 8 Carpathian goats, and 8 Cameroun sheep living in a zoo. Antibodies to phase I and phase II C. burnetii antigens were determined in sera by ELISA. Antibody titres were detected in the range 1:100-1:200. The serum prevalence of phase II and phase I antibodies to C. burnetii antigens was 25 % and 0% in mouflons, 70 % and 0% in goats, 37.5 % and 12.5 % in sheep and 28.3 % and 5 % in fallow deer, resp. Serologic diagnosis of Q fever in animals can be difficult. Some animals may shed C. burnetii and pose a risk for infection prior to the development of antibodies, and some infected animals never seroconvert. The employed ELISA test is a very sensitive assay for C. burnetii, but it is also a labour intensive method and therefore not routinely available.