INVESTIGADORES
AMELOTTI ivana
artículos
Título:
The residual efficacy of a cypermethrin pour-on formulation applied on goats on the mortality and blood intake of Triatoma infestans
Autor/es:
AMELOTTI IVANA; CATALA SILVIA SUSANA; GORLA DAVID ELADIO
Revista:
MEMóRIAS DO INSTITUTO OSWALDO CRUZ.
Editorial:
FUNDACO OSWALDO CRUZ
Referencias:
Lugar: Rio de Janeiro; Año: 2012 vol. 107
ISSN:
0074-0276
Resumen:
Triatoma infestans is the main vector of Trypanosoma cruzi, the aetiological agent of Chagas disease in the Gran
Chaco region of South America. As a frequent blood meal source for triatomine bugs, domestic goats play a key
role in the eco-epidemiology of Chagas disease. The aim of this study was to evaluate the mortality and blood intake
of T. infestans fed on goats that had been treated with different doses of pour-on insecticide. Third-instar nymphs
were fed on goats that had been treated with 0 cc, 5 cc, 10 cc or 15 cc of a pour-on formulation of cypermethrin.
The exposure of T. infestans to animals treated at different post-application intervals revealed a residual activity
of the insecticide. The mortality rate in the treated groups was higher than in the control groups until 30 days post-
insecticide application (p = 0.03), except in the group treated with 5 cc, in which no mortality was detected after
seven days of insecticide application. Rainfall affected the triatomicide effect, reducing the time of residual activity.
The cypermethrin pour-on treatment decreased the blood intake of T. infestans. Thirty days after the cypermethrin
application, nymph mortality was 16% (± 13) with both doses (10 cc and 15 cc). The 15 cc dose did not result in higher
insect mortality or increased persistence compared to the 10 cc dose.