LONG-TERM STUDY OF TOXOPLASMA-GONDII PREVALENCE IN SMALL MAMMALS (INSECTIVORA AND RODENTIA)

In 1981-90, Toxoplasma gondii prevalence in small mammals was investig ated at various locations in the Czech Republic. T. gondii was demonst rated by isolation tests on laboratory-bred mice. A total of 5166 smal l mammals belonging to 17 species was tested. On industrial livestock farms, T. gondii prevalence in small mammals was 0.6 % (n = 2535). On small farms, T. gondii prevalence was 3.7 % (n = 353). T. gondii infec tion is a higher risk factor on small farms. Throughout the year, the T. gondii prevalence in small mammals from farms was the highest in au tumn. Prevalences in military training areas ranged from 0.3 % to 2.7 % (n = 2278). High-risk places in those areas were small pig-rearing f acilities and rubbish tips. No significant changes in T. gondii preval ence in small mammals were mostly found over a period of several years . Parasitological prevalences were 0.4 % (n = 465) in Sorex araneus, 1 .0 % (n = 299) in Clethrionomys glareolus, 0.9 % (n = 1337) in Microtu s arvalis, 2.6 % (n = 39) in Microtus agrestis, 0.8 % (n = 1897) in Ap odemus flavicollis/A. sylvaticus (these two species were not distingui shed), 7.4 % (n = 94) in A. agrarius, and 0.7 % (n = 884) in Mus muscu lus.