Efficacy of cyhalothrin and lambdacyhalothrin against Boophilus microplus (Acari: Ixodidae).
A study was conducted to determine the efficacy of cyhalothrin and lambdacyhalothrin as a whole-body spray and lambdacyhalothrin as a pour-on application on cattle infested with Boophilus microplus (Canestrini). A laboratory bioassay was also done with both spray formulations. Cattle were infested with all parasitic life stages of B. microplus, then treated with 0.007 or 0.01% (AI) concentrations of cyhalothrin as a spray; 0.005, 0.007, or 0.01% (AI) concentrations of lambdacyhalothrin as a spray, or 1% (AI) lambdacyhalothrin as a pour-on. As determined by calculations of the index of reproduction (IR), the 0.007 and 0.01% (AI) cyhalothrin provided 92.4 and 97.3% control, respectively; the 0.005, 0.007, and 0.01% (AI) lambdacyhalothrin provided 92.4, 98.2 (average of two treatments) and 99.3% control, respectively; and the lambdacyhalothrin pour-on treatment provided < 50% control. Bioassay results indicated lambdacyhalothrin to be twice as effective as cyhalothrin against B. microplus.
Davey
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RB
Cattle Fever Tick Research Laboratory, USDA-ARS, Mission, TX 78572.
Ahrens
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EH
George
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JE
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy* / Q000469:parasitology; D007306:Insecticides / Q000627:therapeutic use*; D009570:Nitriles; D011722:Pyrethrins / Q000627:therapeutic use*; D013984:Tick Infestations / Q000188:drug therapy / Q000469:parasitology / Q000662:veterinary*
D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C037304:cyhalothrin