Submitted to: International Conference on Ticks and Tick-Borne Pathogens
Publication Type: Proceedings
Publication Acceptance Date: 11/9/2002
Publication Date: 12/11/2002
Citation: Carroll, J.F. 2002. How specific are host-produced kairomones to host-seekin ixodid ticks?. Experimental and Applied Acarology. 28:155-161. Interpretive Summary: The blacklegged tick is the principal vector of the pathogen causing Lyme disease, a serious human health problem in large areas of the U. S. Finding appropriate hosts is critical to the survival and reproduction of ticks. Host-produced chemical cues (kairomones) aid blacklegged and other ixodid ticks in contacting suitable hosts. Laboratory behavioral trials showed that substances from the coats and external glands of white-tailed deer and dogs arrest and may attract blacklegged, lone star and American dog ticks. In some cases, such as adult American dog ticks, ticks respond to substances from species that they rarely use as hosts.
Technical Abstract: Ixodid ticks respond to host-produced substances (kairomones) that influence the ticks¿ host-finding behavior. In the laboratory adult blacklegged ticks, Ixodes scapularis Say, lone star ticks, Amblyomma americanum L., and American dog ticks, Dermacentor variabilis (Say) became akinetic on residues rubbed from their principal hosts (deer for the former two species and dogs for the latter). However, arrestment also occurred when adults of these species were tested using the same method bioassay, but with host substances reversed (i.e. I. scapularis and A. americanum against canine substances, and D. variabilis against deer gland substances). Although adult D. variabilis exhibited arrestant responses to deer substances and are often found along trials used by deer, they apparently make little use of deer as hosts. It is unclear whether responding to deer-produced kairomones may have disadvantages for D. variabilis. Until the active components of host-produced arrestment kairomones are isolated, identified and evaluated in behavioral tests, this host-finding strategy remains only partially understood.