Resistência à ivermectina em populações de Musca domestica (Diptera: Muscidae) provenientes de granjas de galinhas poedeiras / Resistance to ivermectin in populations of Musca domestica (Diptera: Muscidae) from poultry farms

Bioensaios concentração-resposta foram realizados com o objetivo de estudar o efeito larvicida e detectar possível resistência à ivermectina em dez populações de M. domestica provenientes de granjas de galinhas poedeiras. Para tal finalidade, o meio de cultura para larvas foi tratado com diferentes concentrações de ivermectina (0,015; 0,03; 0,06; 0,125; 0,25 e 0,5 ppm). Atividade larvicida da ivermectina e anomalias nas pupas foram detectadas. A população mais resistente à ivermectina foi Monte Mor, SP (CL= 0,262 ppm e FR= 13,1). As populações de Campinas, SP (CL= 0,141 ppm 50 50 e FR = 7,1), Promissão, SP (CL= 0,110 ppm e FR = 5,5), Santa Cruz da Conceição, SP (CL= 0,102 50 50 ppm e FR = 5,1), Holambra, SP (CL= 0,071 ppm e FR = 3,6) e Hortolândia, SP (CL= 0,068 ppm e 50 50 FR = 3,4) foram mais resistentes que as de Sumaré, SP (CL= 0,052 ppm e FR = 2,6), Sarapuí, SP (CL 50 50 = 0,050 ppm e FR = 2,5) e Itanhandu, MG (CL50 = 0,047 ppm e FR = 2,4). A população mais susceptível à ivermectina foi Grande Porto Alegre, RS (CL50 = 0,020 ppm e FR = 1,0). Os resultados indicam que a ivermectina pode ser eficaz contra larvas deM. domestica. Entretanto, resistência foi suspeitada em algumas das populações, sendo importante a realização de novos estudos nesses locais.

Larvicidal effect and resistance to ivermectin in 10 populations of Musca domestica from poultry farms was evaluated by concentration-response bioassays. For this purpose, the larval growth medium was treated with different concentrations of ivermectin (0.015, 0.03, 0.06, 0.125, 0.25 and 0.5 ppm). As a result, larvicidal activity of ivermectin was observed and some anomalies were detected in pupae. The population from Monte Mor, SP, was the most resistant to ivermectin (LC50 = 0.262 ppm and RF = 13.1). Fly populations from Campinas, SP (LC50 = 0.141 ppm and RF = 7.1), Promissão, SP (LC50 = 0.110 ppm and RF = 5.5), Santa Cruz da Conceição, SP (LC50 = 0.102 ppm and RF = 5.1), Holambra, SP (LC50 = 0.071 ppm and RF = 3.6) and Hortolândia, SP (LC50 = 0.068 ppm and RF = 3.4) were more resistant than the ones from Sumaré, SP (LC50 = 0.052 ppm and RF = 2.6), Sarapuí, SP (LC50 = 0.050 ppm and RF = 2.5), and Itanhandu, MG (LC50 = 0.047 ppm and RF = 2.4). The population most susceptible to ivermectin was that from Grande Porto Alegre, RS (LC50 = 0.020 ppm and RF = 1.0). The results indicate that ivermectin can be effective against larvae ofM. domestica. However, since resistance was suspected in some of the populations studied, it is important to carry out new studies in these places.

Efecto de Beauveria bassiana y Beauveria brongniartii en el control de moscas (Musca domestica) en condiciones de laboratorio y en galpones avícolas / Effect of Beauveria bassiana and Beauveria brongniartii for the house fly (Musca domestica) control on laboratory and poultry sheds conditions

Se realizó un experimento en el estado Trujillo, Venezuela con el objetivo de evaluar en condiciones de laboratorio y en galpones avícolas la patogenicidad de Beauveria brongniartii (cepaLF-05) y Beauveria bassiana (LF-08) sobre Musca domestica. Se determinó que a la dosis de 1,2 x107 conidiosporas/mL para B. brongniartii y B. bassiana los tiempos letales (TL50 y TL95) fueron5 y 9 días y 5 y 6 días, respectivamente. En condiciones de campo las esporas de B. brongniartiiy B. bassiana fueron nebulizadas en el interior de galpones de cría de pollos con una densidad de 7 pollos/m2, a dosis de 9 x 107 conidias/mL en 15L de agua por cada 1200 m2; el porcentaje de reducción poblacional después de nebulizar una vez por semana, durante tres semanas, fue de 13,99 y 100% para B. brongniartii y -35, 91 y 100% para B. bassiana

An experiment was carried out in Trujillostate, Venezuela, in laboratory and poultry shedsconditions in order to study the Beauveria brongniartii(strain: LF-05) and Beauveria bassiana (strain: LF-08) pathogenicity in Musca domestica. With 1.2 x 107conidiospores/mL the lethal times (TL50 and TL95)were 5 and 9, and 5 and 6 days, respectively. In fieldconditions spores of B. brongniartii and B. bassianawere applied inside the poultry sheds (7 chickens/m2)with a dose of 9 x 107 conidia/mL in 15L of water foreach 1200 m2, the percentage of population reductionwere induced after vaporized once a week for threeweeks in 13.99 and 100% for B. brongniartii; and -35,91 and 100% for B. bassiana