Efficacy of synergistic activity of seed oils from (Safflower) and (Watercress) on the lethality of the cattle tick (Acari: Ixodidae).

Background: Ticks and tick-borne diseases are a severe economic and public-health problem for cattle producers. The emergence of acaricide resistance to synthetic chemical treatments has prompted interest in developing alternative tick control methods.

Aim: The main objective of the current research was to identify the chemical structure of and seed oils and to assess their anti-tick properties against ticks both alone and in combination (1:1).

Methods: Analytical methods were used to analyze the chemical components. For assays, adults of were immersed in and seed oils at 100, 125, 200, and 300 mg/ml concentrations; for 5 minutes. Larvae of were dipped in 25, 50, 100, 125, 200, and 300 mg/ml doses of seed oils; the mortality percentage was determined after 24 hours.

Results: The seed oil safflower was mainly composed of linoleic acid (84.48%), followed by palmitic acid (6.54%) and stearic acid (3.77%). Meanwhile, watercress seed oil was mainly composed of linolenic acid (50.78%), gondoic acid (13.57%), linoleic acid (10.58%), palmitic acid (8.02%), and erucidic acid (6.62%). The Adults Immersion Test showed the sensitivity of ticks to and seed oil: seed oil caused (95%) mortality of at 300 mg/ml, while seed oil induced (88.68%) mortality at the same concentration. At a 200 mg/ml concentration, and oil combined caused 100% mortality. Tested oils showed larvicidal efficacy LC50 values for and seed oils were 84.16 and 61.78 mg/ml, respectively, in 24 hours. LC50 value of oils association (50% 50% ) was 47.96 mg/ml.The mixture of seed oils from two plants tested against larvae and adult females at a 1:1 ratio showed synergistic interaction.

Conclusion: Seed oils tested alone, and the mixture could be used as an alternative solution in the fight against ticks.