Triatoma sordida is a peridomestic Triatominae that
could play an important role in the transmission of
Trypanosoma cruzi, although its vectorial competence is
not well known. The aim of this work was to evaluate two
aspects of the vectorial competence: the feeding behaviour and
defaecation patterns, and to compare them with T.infestans.
The feeding and defaecation patterns were studied in adults
and fifth instar nymphs of T. sordida fed ad libitum on a
restrained pigeon. The results showed how the blood meal size
controls excretion behaviour. Blood intake and time to first
defaecation showed a significant negative correlation. Adults
and nymphs frequently defaecated during the blood meal,
reaching the maximum frequency within the first 10 minutes.