Efficacy of 2,6-dichlorophenol lure to control Dermacentor nitens.

This research article examines the effectiveness of 2,6-dichlorophenol (2,6-DCP) as a lure to control Dermacentor nitens, a species of tick. The study found that the 2,6-DCP lure in a specific formulation could control D. nitens for at least 10 days, and suggested further evaluation for long-term effectiveness.

Objectives and Methods of the Research

• The study aimed to evaluate the efficacy of a 2,6-DCP lure in controlling Dermacentor nitens (D. nitens), a tick species. Slow-release formulations of the pheromone, both with and without the insecticide cypermethrin, were prepared.
• Olfactometer bioassays were used to determine the most effective dose of the pheromone and to evaluate whether cypermethrin influences the attractiveness of 2,6-DCP to the ticks.
• Sexually active male ticks were exposed to polypropylene pieces treated with different concentrations of 2,6-DCP, either in a liposphere system or in hexane. The attracted ticks were recorded.

Results from the Laboratory Tests

• The 30 microg dose of 2,6-DCP in the liposphere formulation showed the highest rate of tick attraction and more prolonged pheromone release than the hexane formulation.
• The addition of cypermethrin did not appear to interfere with the attractiveness of the 2,6-DCP lure.

Field Tests and Findings

• After identifying the most effective pheromone formulation and dose, field tests were conducted on horses artificially infested with D. nitens. The lures were attached to the horses’ napes.
• In the first ten days of testing, the number of female ticks on the horses that received the 2,6-DCP treatments was significantly lower than that in the control group, indicating that the lures were effective in controlling the ticks.
• After ten days, however, the number of female ticks was similar in both the control group and the treated groups, suggesting that the effectiveness of the treatment diminished over time.

Conclusions and Future Suggestions

• The results suggest that 2,6-DCP lures, specifically in a liposphere formulation, can control D. nitens for at least ten days by preventing copulation.
• The study indicates the need for further evaluation of the long-term efficacy of the pheromone under natural conditions to validate this control method.
• The researchers also suggest exploring the use of additional lures, such as on a horse’s tail, as an extra measure to control tick populations on the hindquarters of the animal.