Toxicity effect of the acaricide fipronil in semi-engorged females of the tick Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae): Preliminary determination of the minimum lethal concentration and LC50

Autor(es)

de Oliveira, Patricia Rosa ^[1] ; Bechara, Gervasio Henrique ^[2] ; Denardi, Sandra Eloisi ^[1] ; Pizano, Marcos Aparecido ^[3] ; Camargo Mathias, Maria Izabel ^[1]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ UNESP, Inst Biosci, Dept Biol, BR-13506900 Rio Claro, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Dept Anim Pathol, Fac Agron & Vet Sci, BR-14884900 Jaboticabal, SP - Brazil

^[3] Sao Paulo State Univ UNESP, Inst Biosci, Dept Ecol, BR-13506900 Rio Claro, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Experimental Parasitology; v. 127, n. 2, p. 418-422, FEB 2011.
• Citações Web of Science: 10

Resumo

Chemical acaricides, especially fipronil (active ingredient of Frontline (R)), are still the most effective method to control tick populations. In this study, the effectiveness of fipronil was assessed in semi-engorged females of the tick Rhipicephalus sanguineus. A protocol for an in vitro bioassay (AIT) was developed, and the LC(50) (lethal concentration 50%) and 95% confidence interval were determined. Ticks were immersed in Petri dishes with different concentrations of fipronil or distilled water for 2 min, dried, and placed in an incubator for 7 days. Dead R. sanguineus females treated with the 14 concentrations of fipronil were counted daily. Mortality results were compared with the Probit analysis, and the LC(50) and 95% confidence interval were calculated, g (95): LC(50) = 9.647 (4.711 to 13.470). This study was aimed at developing a more appropriate and updated protocol for an in vitro bioassay (AIT - adult immersion test), and providing information on the toxic potential of fipronil (elimination of ectoparasites with lower concentrations) and sensitivity of ticks, especially R. sanguineus, a pest of great interest, due to its occurrence in urban environments. (C) 2010 Elsevier Inc. All rights reserved. (AU)

• Processo FAPESP: 06/52599-0 - Avaliação dos efeitos do fipronil (ingrediente ativo do Frontline) em ovários de carrapatos Rhipicephalus sanguineus (Latreille, 1806) (Acari: Ixodidae) e na medula óssea de roedores
• Beneficiário: Patrícia Rosa de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Doutorado