Data/hora: 13/05/2024 08:57:50

Biblioteca(s): 	Embrapa Pantanal.	
Data corrente: 	02/10/2012	
Data da última atualização: 	25/02/2013	
Autoria: 	DOMINGUES, L. N.; BRASIL, B. dos S. A. F.; BELLO, A. C. P. de P.; CUNHA, A. P. da; BARROS, A. T. M. de; LEITE, R. C.; SILAGHI, C.; PFISTER, K.; PASSOS, L. M. F.	
Afiliação: 	LUÍSA NOGUEIRA DOMINGUES, UFMG; BRUNO DOS SANTOS ALVES FIGUEIREDO BRASIL, UFMG; ANA CRISTINA PASSOS DE PAIVA BELLO, UFMG; ARILDO PINTO DA CUNHA, UFMG; ANTONIO THADEU MEDEIROS DE BARROS, CPAP; ROMÁRIO CERQUEIRA LEITE, UFMG; CORNELIA SILAGHI, UNIVERSITAT MUNCHEN; KURT PFISTER, UNIVERSITAT MUNCHEN; LYGIA MARIA FRICHE PASSOS, UFMG - UNIVERSITAT MUNCHEN.	
Título: 	Survey of pyrethroid and organophosphate resistance in Brazilian field populations of Rhipicephalus (Boophilus) microplus: Detection of C190A mutation in domain II of the para-type sodium channel gene.	
Ano de publicação: 	2012	
Fonte/Imprenta: 	Veterinary Parasitology, v. 189, n.2-4, p. 327-332, 2012.	
Idioma: 	Inglês	
Conteúdo: 	The cattle tick Rhipicephalus (Boophilus) microplus causes expressive damage to livestock in Brazil and other countries. Its control is becoming more difficult due to the development of resistance in populations. Early detection of resistance can help in developing effective control strategies. This study evaluated the susceptibility of R. microplus to cypermethrin and chlorpyriphos and was the first attempt to identify the mechanism of resistance (target site insensitivity) in cattle tick populations from Minas Gerais state (Southeastern Brazil). Engorged female ticks were collected from 10 ranches within the state of Minas Gerais, and susceptibility was evaluated with the larval packet test (LPT) using technical grade cypermethrin and chlorpyriphos. It was possible to analyze LPT results of seven populations. Target site insensitivity was investigated in all 10 isolates by using molecular approaches for detection of the T2134A substitution within the domain III S6 segment and the C190A in the domain II S4-5 linker from the para-type sodium channel gene. LPT showed that all seven populations were resistant to cypermethrin with resistance ratio (RR) ranging from 16.0 to 25.0 and 85.7% were resistant to chlorpyriphos (RR = 2.2?15.6). Although the T2134A mutation was not detected, the C190A mutation was highly prevalent, being present in 82?100% of the alleles sampled in field populations. A significant correlation was found between the LC50 values for cypermethrin and the frequency of the C190A mutation suggesting that it might be responsible for the phenotypic resistance detected.	
Palavras-Chave: 	Allele-specific PCR; Cattle tick; Chlorpyriphos; Larval packet test; Target site insensitivity.	
Thesaurus Nal: 	cypermethrin.	
Categoria do assunto: 	O Insetos e Entomologia	
Registro original: 	Embrapa Pantanal (CPAP)	
Exemplares: 	CPAP - (58487-1) - UPC - SP - PP - SP17621 -  - 17621 - DIS