EFFICACY OF PHEROMONE ACARICIDE-IMPREGNATED TAIL-TAG DECOYS FOR CONTROLLING THE BONT TICK, AMBLYOMMA-HEBRAEUM (ACARI, IXODIDAE), ON CATTLE IN ZIMBABWE

A large-scale field test using pheromone-acaricide-impregnated plastic tail-tag decoys demonstrated excellent efficacy of these devices for control of the bent tick, Amblyomma hebraeum, on cattle in Zimbabwe. T he tail tags were impregnated with a mixture containing o-nitrophenol, methyl salicylate, 2,6-dichlorophenol and phenylacetaldehyde and one of three different acaricides (cyfluthrin, flumethrin or alphacypermet hrin). o-Nitrophenol and methyl salicylate are components of the A. he braeum attraction-aggregation-attachment pheromone, while 2,6-dichloro phenol and phenylacetaldehyde are proven attractants for this tick. Bo th o-nitrophenol and methyl salicylate were lost gradually from the ta gs over 12 and 14 week periods, respectively. In field trials, tick co unts were compared between cattle that received tail tags either impre gnated with pheromone mixture alone, cyfluthrin and pheromone mixture, flumethrin and pheromone mixture, alphacypermethrin and pheromone mix ture or were left untreated. During the first 3 month trial period, co ntrol of adult bent ticks was 94.9% with cyfluthrin tail tags and 87.5 % with flumethrin tail tags. In general, there was no significant diff erence in bent tick numbers on cattle without tags and those with tail tags containing pheromone only. When the trial was repeated for anoth er 3 month period, control of bent ticks with tail tags containing cyf luthrin and flumethrin was 99.3 and 95.1%, respectively. However, cont rol of bent ticks using alphacypermethrin was only 79.2%. Overall, ret ention of tail tags was excellent although some loss was encountered d uring the rainy season. In addition to controlling bent ticks, the tai l tags provided moderate control of other tick species (Rhipicephalus evertsi evertsi, Rhipicephalus zambeziensis and Hyalomma spp.) simulta neously infesting cattle in the trials.