Journal of Medical Entomology (2002) 39, 742-746

Robert L. Bossard, Michael W. Dryden and Alberto B. Broce (2002)
Insecticide susceptibilities of cat fleas (Siphonaptera: Pulicidae) from several regions of the United States
Journal of Medical Entomology 39 (5), 742-746
Abstract: Eleven cat flea, Ctenocephalides felis (Bouchè), strains, seven field-collected and four laboratory-colonized, were assayed for susceptibilities to five insecticides (carbaryl, chlorpyrifos, malathion, permethrin, and pyrethrin) with an insecticide-treated, horizontally-oriented, Nylon 6,6 disk in a test tube. The pyrethrin was synergized using piperonyl butoxide (PBO). Flea mortality at two doses was recorded after 4 and 24 h exposures. The field strains from Texas and Florida tolerated carbaryl, chlorpyrifos, and malathion; and carbaryl and PBO-synergized pyrethrin, respectively. Tolerance was observed in a field strain from Kansas against malathion. Colonies from California and North Carolina were susceptible to malathion and PBO-synergized pyrethrin, and chlorpyrifos and permethrin, respectively, but three colonies showed tolerance. The insecticidal response of the California colony varied; when exposed to a chlorpyrifos dose of 10 mg (AI)/m² for 24 h, at various times had mortality of 3–100%. With a PBO-synergized pyrethrin dose of 396 mg (AI)/m² for 4 h, the mortality ranged between 4.2 and 97%. Colonized strains were more susceptible than field strains at 4 h exposure to all insecticides except PBO-synergized pyrethrin. Colonized strains survived better in control tubes. The colony strains' susceptibility and variability are of considerable importance because these strains are used for flea product efficacy evaluations and bioassays. The differences in susceptibility between laboratory colonies and the field strains suggested development of both adaptation to colonization, and extensive, multiple cross-resistance to insecticides in field strains. Varying susceptibility of cat fleas may affect control success.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Robert L. Bossard

Research topic(s) for pests/diseases/weeds:
control - general
pesticide resistance of pest

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Ctenocephalides felis		U.S.A. (SW)
	Ctenocephalides felis		U.S.A. (mid S)
	Ctenocephalides felis		U.S.A. (SE)