Attraction of Ixodes species Amblyomma americanum and Dermacentor variabilis to hematophagous insect stimulatory chemicals and chemical combinations

Amblyomma americanum and Dermacentor variabilis ticks vector pathogens that cause diseases in both human and mammal populations. The risk of disease is primarily associated with the feeding behavior of the tick species. Host semiochemicals are important sensory stimuli involved in host seeking and feeding behavior that convey information on host location and proximity as well as family type. Literature analysis of various blood-feeding hexapod species identified seven common attractive host semiochemicals: CO2, L-lactic acid, acetone, carboxylic acids, nitrogenous wastes, sulphides and 1-octen-3-ol. To further understand host attraction in these two tick species these seven hematophagous insect stimulatory chemicals were investigated. Laboratory tests were conducted using a two-choice olfactometer to screen chemicals for attractive behavioral responses. Chemicals proven attractive were tested in field trials to determine efficacy of attraction. Dose-response curves where established for each chemical and data collected indicating percent response. Results will provide important information in evaluating the development of a tick bait system to control environmental populations.