Particles with particle size of not > 10 mu m, comprise: (a) uncharged polyacrylate (b) cationic polyacrylate, which carries positively charged functional groups (c) at least one active substance and (d) optionally other polymers, auxiliaries or additives. An independent claim is also included for producing the particles, comprising (i) preparing a solution of the components (a)-(d) in a small extent with water-miscible solvent or solvent mixture, (ii) dispersing the solution in an aqueous phase, optionally containing additives and solvent or solvent mixture up to saturation to produce a fine, stable emulsion, and (iii) removing the solvent or solvent mixture from the emulsion droplets by evaporation (solvent evaporation process) to obtain an aqueous suspension, or spray-drying to obtain a dry powder and #an agent comprising the particles. ACTIVITY : Antiparasitic Acaricide. The acaricide activity of the agent was tested in vivo in beagle-type dogs (21-30 months old and weighing 8.8-15.5 kg) by spraying the agent containing flumethrin particles (15%) and polymethyl methacrylate on whole body of the dog. The results showed that agent reduces the number of ticks after 50 study days (0) compared to untreated dogs (14). MECHANISM OF ACTION : None given.
