Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Effect of Temperature and the Synergist Pbo on Imidacloprid Toxicity to Catfleas (Siphonaptera: Pulicidae)

Authors
item Richman, Dina
item Koehler, Philip - UNIV OF FLORIDA
item Brenner, Richard

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 21, 1999
Publication Date: N/A

Interpretive Summary: Imidacloprid is the active ingredient of Advantage flea control treatment. This treatment is currently sold only by veterinarians and is dispensed in individual tubes containing the active ingredient in an oil. The oil is applied to the shoulder region of the pet and spreads over the surface of the animal within 24 hours. There is potential to market imidacloprid as an indoor and outdoor treatment that would need to operate over a wide temperature range, as opposed to operating at an animal's body temperature. The toxicity of imidacloprid to cat fleas was investigated at 20o, 26o, 30o and 35oC. Imidacloprid was most toxic to adult cat fleas at 35oC and to larvae at 20oC. Piperonyl butoxide (PBO), a synergist added to imidacloprid (5:1), increased toxicity 16-fold at 26oC against adults, but had no effect at 35oC. No synergism occurred in larvae at 20oC, but addition of PBO doubled toxicity at both 26o and 30oC. Imidacloprid was more toxic to both adult and larval cat fleas than were most organophosphates, carbamates, pyrethroids, growth regulators, and borates tested by other researchers. Moreover, PBO can be used to synergize imidacloprid premise treatments (20-30oC), but not the pet treatments because no synergism occurred in adult fleas at 35oC (approximate fur temperature).

Technical Abstract: The toxicity of imidacloprid to cat fleas held on glass was investigated at 20o, 26o, 30o, and 35oC. Imidacloprid was most toxic to adult cat fleas at 35oC and to larvae at 20oC. Piperonyl butoxide (PBO), a synergist added to imidacloprid (5:1), increased toxicity 16-fold at 26oC against adults, but had no effect at 35oC. No synergism occurred in larvae at 20oC, but addition of PBO doubled toxicity at both 26o and 30oC. Imidacloprid was more toxic to both adult and larval cat fleas compared with most organophosphates, carbamates, pyrethroids, growth regulators, and borates tested by other researchers. However, PBO can be used to synergize imidacloprid premise treatments (20-30oC), but not pet treatments because no synergism occurred in adult fleas at 35oC (approximate fur temperature).

Last Modified: 10/25/2014
Footer Content Back to Top of Page