Production of pheromones by artificially fed males of the tick Amblyomma maculatum (Acari: Ixodidae)

Aggregation-attachment pheromones are produced only by male ticks of the genus Amblyomma that have imbibed. blood for at least 8 d From their mammalian hosts. This report demonstrates that production and release of aggregation-attachment pheromones by Amblyomma maculatum (Koch) males can be induced in vitro by using nonblood media, artificially introduced through capillary tubes, into the male ticks. The presence of these pheromones is demonstrated by using both biological observations on bovine hosts and in vitro experimentation with petri dishes. The attraction of unfed female ticks to the artificially fed males (using the petri dish method) was significantly higher (P < 0.001) than the attraction of unfed females to unfed males. Similarly, attraction and attachment were recorded on bovine hosts. Only 62.8 +/- 17.5% of the females released attached to the bovine host. Of these, 61.9 +/- 19.37% attached. around artificially fed males that were placed on the bovine 24 h earlier. This percentage did not differ significantly from the 81.4 +/- 7.1% of the total that attached around males that fed naturally for 8 d. In comparison, only 33.3 +/- 21.9% of the total number of females placed on the host did so after being fed 1 d (control group). The possibility of using capillary feeding as a new tool for investigating the physiology and reproductive behavior of blood- sucking arthropods is discussed.