Comparison of several compounds against ectoparasites

Comparison of In Vitro and In Vivo Ectoparasiticide Activity of
Experimental Benzimidazole-Carbamate with Permethrin and Amitraz

Authors: White W. Hunter; Bauer Steven M.; Zhao Xiaowen; Gutierrez
Jesus A.; Smith Charles K.

Source: Journal of Medical Entomology, March 2005, vol. 42, no. 2, pp.
207-211(5)

Publisher: Entomological Society of America



Abstract:
A series of in vitro and in vivo bioassays were conducted to assess the
ectoparasiticide activity of
isopropyl-4-nitro-2,6-bis(trifluoromethyl)-1-benzimidazole-carbamate,
an experimental benzimidazole-carbamate class compound. This compound
was less potent than permethrin against ectoparasiticide-susceptible
larvae of the lone star tick, Amblyomma americanum (L.) (Acari:
Ixodidae); larvae of the southern cattle tick, Boophilus microplus
(Canestrini); and adult stable fly, Stomoxys calcitrans (L.) (Diptera:
Muscidae) in vitro, but it was significantly more potent than
permethrin against the Santa Luiza strain of B. microplus known to
possess high-level resistance to amitraz and pyrethroids. In contrast,
the benzimidazole-carbamate was substantially more efficacious than
permethrin when applied topically onto rats that were infested with A.
americanum nymphs. These results suggest that this experimental
compound may be a viable candidate ectoparasiticide that retains
significant activity against resistant B. microplus and also suggests
that the benzimidazole-carbamate chemistry may be useful for addressing
the growing problem of resistance in ectoparasites.

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