BESNOITIA SP (PROTOZOA, TOXOPLASMATINAE) FROM AKODON MONTENSIS (RODENTIA, CRICETIDAE) IN SANTA-CATARINA STATE, BRAZIL

Tissue cysts of Besnoitia sp. were found in muscles and several organs from a naturally infected Akodon montensis captured in the rural area of the municipality of Timbo, Santa Catarina State, in southern Brazi l. Indirect fluorescence and enzyme-linked immunosorbent assays carrie d out with sera from mice chronically infected with Toxoplasma gondii and Besnoitia sp. showed, as expected, a stronger reaction against hom ologous than heterologous antigens. No cross-protection was observed i n mice immunized with T. gondii when challenged with Besnoitia sp. Thi s is the first description of a natural infection of A. montensis by p arasites of the genus Besnoitia sp. in Brazil.