Frequency of anti-Leptospira spp. antibodies in dogs and wild small mammals from rural properties and conservation units in southern Brazil

Abstract Leptospirosisis a disease of worldwide distribution that affects man and several animal species. Domestic and wild animals can behave as reservoirs of the agent. The aim of this study was to evaluate the frequency of anti- Leptospiraspp. antibodies in dogs and wild small mammalsfrom rural properties and conservation units of three municipalities of Rio Grande do Sul State, Brazil. Sera were collected from 192 domestic dogs and 132 small mammals, namely rodents of the Cricetidaeand Caviidaefamilies and marsupialsof the Didelphidae family. The study used Microscopic Agglutination Test (MAT) against 23 serovars of Leptospiraspp. Overall, 9.90% (19/192) dogs, and 1.51% (2/132) small mammalswere seropositive. Leptospira interrogansserovar Australis was the most frequent serovar in dogs and antibodies against L. interrogans serovar Pomona were detected in a dog and a small mammalbelonging to the same municipality. We conclude that in the regions studied the frequency of seropositivity in dogs is low, and leptospires do not seem to be circulating in small mammals, yet, further research is necessary to assess the real role that these animals may have for leptospirosisin the studied areas. This is the first serological survey in small mammals, including wild rodents, in the area that encompasses conservation units of great importance to Rio Grande do Sul state.