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 ge nus Amblyomma that have imbibed. blood for at least 8 d From their mammalia n hosts. This report demonstrates that production and release of aggregatio n-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 demonstrat ed by using both biological observations on bovine hosts and in vitro exper imentation with petri dishes. The attraction of unfed female ticks to the a rtificially fed males (using the petri dish method) was significantly highe r (P < 0.001) than the attraction of unfed females to unfed males. Similarl y, attraction and attachment were recorded on bovine hosts. Only 62.8 +/- 1 7.5% 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 bo vine 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 plac ed 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 a nd reproductive behavior of blood- sucking arthropods is discussed.