Biological and physiological parameters of Triatoma brasiliensis, Triatoma infestans, and Triatoma pseudomaculata were studied and compared. T. brasiliensis, reared on mice, showed a faster evolutionary cycle from first stage to adult and higher fecundity, when compared to the other species. T. infestans showed the fastest blood intake in both hosts tested, followed by T. brasiliensis and T. pseudomaculata. Clotting tests using salivary gland extracts of T. brasiliensis presented intermediary values of anti-clotting activity when compared to T. infestans and T. pseudomaculata.