SEROLOGIC SURVEY OF TRICHINOSIS IN WILD MAMMALS KEPT IN A MEXICO-CITYZOO

A serologic survey of Trichinella infection was carried out to determi ne the prevalence of this parasitosis among wild mammals kept in capti vity at the Chapultepec Zoo, This was prompted by the necropsy finding of a heavy Trichinella infection in a Canadian polar bear (Ursus mari timus) that had been kept at the Zoo for more than 11 years, The paras ites recovered were identified as T. nativa (T2), A serologic study ba sed on ELISA and Western blot analysis was performed in serum samples from two polar bears (U. maritimus), six wolves (Canis lupus); nine fo xes (Urocyon cinereoargenteus); seven coyotes (Canis latrans); nine ja guars (Panthera onca); ten lions (Panthera leo); 11 tigers (Panthera t igris); six panthers (Panthera pardus); eight leopards (Panthera pardu s); two lynxes (Lynx rufus); five pumas (Felis concolor); one yagouaro undi (Felis yagouaroundi); and one ocelot (Felis pardalis), In these a ssays, 25% and 27% of the samples studied were positive using total mu scle larva extract from T. nativa (T2) or T. spiralis (T1), respective ly, When T. spiralis (T1) excretory/secretory products or surface/stic hosomal antigens were used, 15 and 13% positivity was obtained respect ively, The reactivity rates obtained among the different groups varied from 11 to 83%, wolves having the highest infection rate, Western blo t analysis of positive ELISA sera showed an antigenic recognition patt ern characteristic of animals infected with Trichinella.