biostudies-literatureUnknown78(10)Kotze ACElanco Animal HealthCommonwealth Scientific and Industrial Research Organisation<h4>Background</h4>The sheep blowfly, Lucila cuprina, is a myiasis-causing parasite responsible for significant production losses and welfare issues for the Australian sheep industry. Control relies largely on the use of insecticides. The pyrimidine compound, dicyclanil, is the predominant control chemical, although other insecticides also are used, including imidacloprid, ivermectin, cyromazine and spinosad. We investigated in vitro resistance patterns and mechanisms in field-collected blowfly strains.<h4>Results</h4>The Walgett 2019 strain showed significant levels of resistance to both dicyclanil and imidacloprid, with resistance factors at the IC₅₀ of 26- and 17-fold, respectively, in in vitro bioassays. Co-treatment with the cytochrome P450 inhibitor, aminobenzotriazole, rePest management science4195-4206https://www.ebi.ac.uk/biostudies/studies/S-EPMC9540573biostudies-literatureResistance to dicyclanil and imidacloprid in the sheep blowfly, Lucilia cuprina, in Australia.PMC9540573Ruffell APBagnall NHKotze ACGeorge SDRolls NMfalseResistance to dicyclanil and imidacloprid in the sheep blowfly, Lucilia cuprina, in Australia.<h4>Background</h4>The sheep blowfly, Lucila cuprina, is a myiasis-causing parasite responsible for significant production losses and welfare issues for the Australian sheep industry. Control relies largely on the use of insecticides. The pyrimidine compound, dicyclanil, is the predominant control chemical, although other insecticides also are used, including imidacloprid, ivermectin, cyromazine and spinosad. We investigated in vitro resistance patterns and mechanisms in field-collected blowfly strains.<h4>Results</h4>The Walgett 2019 strain showed significant levels of resistance to both dicyclanil and imidacloprid, with resistance factors at the IC₅₀ of 26- and 17-fold, respectively, in in vitro bioassays. Co-treatment with the cytochrome P450 inhibitor, aminobenzotriazole, re2022-01-01T00:00:00Z2022 Oct2025-04-22T01:50:49.319Z2025-04-05T20:10:28.376ZS-EPMC95405733569091210.1002/ps.7037