Small mammals as reservoirs and transmitters of leptospires in livestock-breeding farms and their surroundings.

From 1976 to 1978, we examined 1723 wild small mammals, representing 15 species, from three animal production farms and their surroundings in the Trebon basin, south Bohemia, in order to detect antibodies against leptospirosis. Antibodies were found against the serovars grippotyphosa, sorex-jalna, sejroe and/or istrica. The serological positivity was higher in wet grassland stands and fields bordering fishponds. The dominant serovar was grippotyphosa against which antibodies were detected in 8 species of exoanthropic and synanthropic mammals. Owing to the wide ecological valence of the main natural reservoir of L. grippotyphosa--Microtus arvalis, this serovar was present even within the confines of the farms. M. arvalis, together with Apodemus sylvaticus, entering the farm buildings in the cold winter months, can introduce the serovar to the stables housing the farm animals.