Application of Cypermethrin-Coated ZnS and ZnO Nanoparticles against Rhipicephalus Ticks

Rhipicephalus ticks are described as important ticks impacting the costs of livestock rearing and by-products sale. The prevalence and response of ticks towards cypermethrin sprays indicate the need to implement the rational use of acaricides. In our previous studies, ZnO nanoparticles were shown to inhibit the major life-cycle stages of Hyalomma ticks, indicative of promising application of nanomaterials against the hard ticks. The current study was designed to probe into one of alternative options to curtail Rhipicephalus ticks by employing cypermethrin-coated nanoparticles of ZnO (C-ZnO NPs) and ZnS (C-ZnS NPs). The nanocomposites showed a roughly spherical type of morphology and various size dimensions upon characterization using SEM and EDX. Female ovipositioning was declined up to only 48% in ZnS and up to 32% in ZnO NPs even after 28 days in vitro. Similarly, the larval hatching was also impacted, leading to a hatching percentage of 21% and 15% by application of C-ZnS NPs and C-ZnO NPs, respectively. The LC(90) in female adult groups were 3.94 mg/L and 4.27 mg/L for the C-ZnO NPs and C-ZnS NPs groups, respectively. Similarly, the larval groups had LC(90) of 8.63 and 8.95 mg/L for the C-ZnO NPs and C-ZnS NPs groups. The study is a proof of the concept for incorporating effective and safe nanocomposites as acaricides. The studies on the efficacy and spectrum of non-target effects of nanomaterial-based acaricides can further refine the research on finding novel alternatives for tick control.