@article {Rust:July 2005:0022-2585:631,
	author = "Rust, M. K.",
	author = "Denholm, I.",
	author = "Dryden, M. W.",
	author = "Payne, P.",
	author = "Blagburn, B. L.",
	author = "Jacobs, D. E.",
	author = "Mencke, N.",
	author = "Schroeder, I.",
	author = "Vaughn, M.",
	author = "Mehlhorn, H.",
	author = "Hinkle, N. C.",
	author = "Williamson, M.",
	title = "Determining a Diagnostic Dose for Imidacloprid Susceptibility Testing of Field-Collected Isolates of Cat Fleas (Siphonaptera: Pulicidae)",
	journal = "Journal of Medical Entomology",
	volume = "42",
	year = "July 2005",
	abstract = "The susceptibility of four laboratory strains of cat fleas, <I>Ctenocephalides felis</I> (Bouch&#233;), to imidacloprid was determined by three different laboratories, by using a standardized bioassay protocol. The probit lines generated by the different laboratories were very similar, with LC<SUB>50</SUB> values ranging from 0.32 to 0.81 ppm. Based on these data, a diagnostic dose (DD) of 3 ppm imidacloprid in larval rearing media was provisionally identified for detecting shifts in tolerance, possibly as a consequence of incipient imidacloprid resistance. None of the larvae from the susceptible laboratory strains survived the DD. Eighteen field-collected isolates were evaluated for their susceptibility to imidacloprid and to validate a DD of 3 ppm. Probit lines from 18 field-collected isolates were very similar, with LC<SUB>50</SUB> values ranging from 0.14 to 1.52 ppm. When exposed to the DD, between 3 and 10% of the exposed larvae emerged as adults from only three of the 18 isolates. All other field isolates gave 100% mortality at the DD. Under the criteria established (&#62;5% survivorship at 3 ppm), two isolates would be established on mammalian hosts and more extensive tests conducted to exclude or confirm the presence of resistance. The DD of 3 ppm is robust enough to eliminate most of the susceptible isolates collected until today, yet low enough to identify possible isolates for further testing.",
	pages = "631-636(6)",
	url = "http://www.ingentaconnect.com/content/esa/jme/2005/00000042/00000004/art00017"
}