A review of the role of pheromones in the control of Amblyomma ticks on livestock

Abstract

As external parasites of livestock, ticks of the genus Amblyomma have a significant impact on animal health and production globally. Furthermore, Amblyomma ticks are vectors of diseases affecting livestock, but humans as well. Amblyomma variegatum and Amblyomma hebraeum, both found in Southern Africa, are vectors of heartwater (Ehrlichia ruminantium) and African tick bite fever (Rickettsia africae) affecting ruminants and humans, respectively. Beyond the current impact on animal and human health, there is potential for even more significant effects on animal production if the geographic range of these tick-borne pathogens will shift and expand beyond the traditional endemic areas. A literature study was performed to evaluate the constituents of the attraction-aggregation-attachment (AAA) pheromones emitted by Amblyomma ticks and their effects on the behaviour of these ticks. Previous applications of these pheromones in tick control were studied and the difficulties experienced in field studies evaluated. Here, a novel method of tick control on cattle is proposed, based on the use of a legband impregnated with pheromones and acaricides, to attract and kill Amblyomma ticks. Specific recommendations are made to assess the efficacy and feasibility of such a control device under field conditions.