RESUMEN
A serological survey to search for antibodies against T. spiralis was performed in free roaming rats (n=64) and mice (n=35) caught in zoological park from Mexico City. Serum samples were analyzed by ELISA and immunoelectrotransfer blot assay (EIBT). None serum show positive absorbance values in ELISA nor recognized T. spiralis specific antigenic fractions in EIBT. However, two rat samples recognized three antigens of 31,37 y 55 kDa, while one of them reacted with two additional antigens of 64 and 67 kDa. As it is known that the antigen epitope profiles varied among trichinella species, it could be possible that in rats, there is 3 percent of antibody prevalence agains trichinella sp.; however, due that other organisms could induce the production of cross-reacting antibodies, such conclusion can not be supported at all. These results suggest that T. spiralis was not part of helminthological fauna in these rodents