Potencial de cinco espécies de peixe como método de controle biológico de larvas de Aedes aegypti, em condições de laboratório, no Ceará

Abstract

Dengue fever has been shown to be one of the main public health problems in Ceará the principal vector is the Aedes aegypti mosquito In recent decades chemical control has been under question, both due to the insect’s selective resistance capacity and for environmental reasons Thus the use of biological alternatives has been encouraged worldwide Consequently the objective of this study was to evaluate 5 fish species that have been used as an alternative for the control of Aedes aegypti larvae in domestic water tanks in the State of Ceará Brazil The species evaluated were Betta splendens Trichogaster trichopteros Astyanax fasciatus e Poecilias reticulata and sphenops Larvae-eating capacity prefered predation locations and resistence to chlorine were evaluated All five species had a high larvae-eating capacity; Betta splendens and Poecilias were noteworthy for their larger capacity in relation to weight and body size Astyanax fasciatus and Betta splendens appeared to survive well without the presence of larvae or artificial food in the domestic water tanks whilst Poecilias presented a significant weight loss during the 5-week evaluation Regarding the location of predation it was observed that Poecilias spent most of the time at the surface whereas Trichogaster and Betta had greater mobility in the container As to chorine resistance Poecilias had a significant mortality when exposed to concentrations of 0.5mg/litre while other species of Betta and Trichogaster were able to survive concentrations up to 4.00mg/litre Therefore it was possible to demonstrate that the 5 species can be used as biological control alternatives although each one is indicated for different water tanks due mainly to the food available and the chlorine concentrations.