title: Efficacy of some pyrethroids against a strain of the rabbit ear mite (Psoroptes cuniculi): an unusual cross-resistance pattern.
abstract: An in vitro immersion bioassay was used to compare the efficacy of selected pyrethroids against a deltamethrin-resistant strain of rabbit ear mite (Psoroptes cuniculi). A lack of cross-resistance between bromo (deltamethrin) and chloro analogues (cypermethrin) of alpha-cyano-3-phenoxybenzyl-dihalovinyl-dimethylcyclopropane carboxylate was detected. Whereas deltamethrin proved to be inactive (48-h mortality 21.9% at 1000 mg/kg), each cypermethrin isomer mixture tested, including alpha-cypermethrin [IR(cis) alpha S + 1 S (cis) alpha R] and theta-cypermethrin [1R(trans) alpha S + 1 S (trans) alpha R] and their mixture at a ratio of 4/6, beta-cypermethrin, showed high efficiency (48-h mortality > or = 95% at 1000 mg/kg).
authors.affiliation: Chinoin Pharmaceutical an Chemical Works Co. Ltd., AgChem BU, Budapest, Hungary.
authors.forename: L
authors.initials: L
authors.lastname: Pap
authors.forename: P
authors.initials: P
authors.lastname: Sárközy
authors.forename: R
authors.initials: R
authors.lastname: Farkas
authors.forename: E
authors.initials: E
authors.lastname: Bleicher
authors.forename: A
authors.initials: A
authors.lastname: Szegö
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D004351:Drug Resistance; D004423:Ear / Q000469:parasitology; D007306:Insecticides / Q000633:toxicity*; D008925:Mites / Q000187:drug effects*; D009570:Nitriles; D011722:Pyrethrins / Q000633:toxicity*; D011817:Rabbits
chemical_list: D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C017160:cypermethrin; C017180:decamethrin