cyhalothrin and Tick-Infestations

This paper examines the efficacy of 10% lambdacyhalothrin-impregnated plastic tags and a deltamethrin pour-on preparation in protecting red grouse chicks from parasitism by ticks and subsequent infection with the louping-ill virus. In 1995, ten red grouse hens (Lagopus lagopus scoticus) in a free-living population in north-east Scotland were fitted with lambdacyhalothrin-impregnated plastic tags, glued to radio transmitters. Chicks of more than 10 days of age from a further ten untreated radio-collared hens were caught and fitted with individual tags to the ptagium. Both treatments significantly reduced tick burdens in the short term. The number of larvae and nymphs on chicks up to 45 days was less under both treatments than on control chicks and tagged chicks had fewer nymphs than chicks from treated hens. Nevertheless, treatments did not reduce viral infection rates nor increase survival to 10 weeks, possibly explained by incomplete treatment of tagged broods and/or direct or indirect mortality due to tags. In 1996 chicks in ten broods from hens with radio transmitters were individually treated at 14 days of age at a rate of 1 mg/kg of chick with a deltamethrin pour-on preparation. This preparation significantly reduced the number of larvae and nymphs on grouse chicks 7-10 days after application below the number on untreated controls. At 20 days from application, however, only larval numbers were lower on treated chicks. Nevertheless louping-ill virus infection prevalences were significantly reduced at 35 days of age and survival of chicks to 10 weeks increased.

Topics: Animals; Bird Diseases; Birds; Dogs; Insecticides; Ixodes; Nitriles; Pyrethrins; Tick Control; Tick Infestations

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.

Topics: Animals; Cattle; Cattle Diseases; Insecticides; Nitriles; Pyrethrins; Tick Infestations

A new synthetic pyrethroid, cyhalothrin, has been evaluated as both a sheep dip and a jetting fluid for the control of body lice (Damalinia ovis), face lice (Linognathus ovillus), foot lice (Linognathus pedalis) and the sheep ked (Melophagus ovinus). A dip wash concentration of 1.25 ppm cyhalothrin eradicated D. ovis from sheep. A jetting fluid at a concentration of 20 ppm also eradicated D. ovis. In the field cyhalothrin was evaluated at 20 ppm as a dip wash and at 50 ppm as a jetting fluid. These field trials confirmed the ability of cyhalothrin to eradicate D. ovis from short and long-woolled sheep. The sucking lice, L. ovillus and L. pedalis, were also found to be very susceptible to cyhalothrin at a dip wash concentration of 20 ppm, but it was necessary to treat the predilection sites infested by these parasites twice within a 3-week period to achieve their eradication. Sheep ked (M. ovinus) were eradicated from an infected flock of sheep after plunge dipping in cyhalothrin at 20 ppm.

Topics: Administration, Topical; Animals; Lice Infestations; Nitriles; Pyrethrins; Sheep; Sheep Diseases; Tick Infestations

Cyhalothrin, a novel synthetic pyrethroid, was evaluated for control of the major resistant strains of the cattle tick (Boophilus microplus) and for control of the buffalo fly (Haematobia irritans exigua) on cattle. In regulated treatment trials with 0.007% cyhalothrin, greater than 99% control of the Biarra, Mackay, Mt Alford, DDT resistant and Ulam cattle tick strains was obtained. Protective-period trials were conducted in which animals which had been sprayed with 0.007% cyhalothrin then received a continuing heavy challenge of the organophosphate-resistant Biarra tick strain. The first semi-engorged adult ticks appeared no earlier than 27 days after treatment, which corresponds to a minimum protective period against reinfestation of 7 days. Protective-periods ranging from 7 to 15 days were obtained in trials that were conducted. Field trials on cattle confirmed that dipping in 0.007% cyhalothrin provided a high level of tick control and a minimum of 7 days protective period against reinfestation. Thus a 28 day treatment interval was employed. It was possible to further extend dipping intervals to as long as 7 weeks once tick populations were reduced on the pasture. Furthermore at least 28 days protection from reinfestation with buffalo fly was also provided. In backspraying trials on cattle, 200 mg cyhalothrin applied to each animal as an 0.2% aqueous emulsion gave greater than 28 days protection against reinfestation with buffalo fly.

Topics: Administration, Topical; Animals; Cattle; Cattle Diseases; Chemical Phenomena; Chemistry; Diptera; Insect Control; Insecticides; Myiasis; Nitriles; Pyrethrins; Species Specificity; Tick Control; Tick Infestations; Ticks