RESUMO
Reservoirs of T. cruzi were studied in the ecological reserve "El Zapotal", in the Tuxtla Gutiérrez municipality located in the state of Cchiapas. the parasite transmissión cycle exists in that area. A totral of 73 specimens of B different mammal species were trapped alive. Xenodiagnosis tests showed that 11% of them were positive for T. cruzi. Blood concentration exam, blood culture, serology (CIEP) and histological exam were carried out in 65 specimens fromthe total captured T. cruzi positive results in these tests were 1.5, 3.6 and 6.2% respectively. None of the 73 specimens were positive in the histological ewxams. Amastigote nests were found in cardiac tissue of mice, which were inoculated with triatomine bugs dejections collected from those specimens used from xenodiagnosis testing or by the inoculation of parasites grown in axenic blood cultures. These results indicated that there is a sylvan cycle which is maintained by mammal species, which are plundering this geographic area