Laboratory methods of estimation of biological efficiency of plant protection rodenticides from voles of genus Microtus

Abstract

Long-term laboratory studies resulted in the improvement of the regime of keeping and testing of voles: Microtus arvalis Pall., M. rossiaemeridionalis Ognev and M. socialis Pall.. Methods of primary testing of new rodenticides and bait products, determination of LD50 and estimation of resistance to anticoagulant rodenticides were adapted for gray voles of the genus Microtus. Rodenticides testing on laboratory bred individuals in group testing scheme included experimental reconstruction of field treatments conditions, such as cool temperature regime and alternative juicy feed. The test methods with temporally kept wild-caught Microtus voles were used in the study of level of resistance and bait preference in certain habitats, and also as an additional method for testing the water vole Arvicola terrestris L., for which the method of maintenance of laboratory colonies, evaluated for Microtus voles, were not applicable. New scheme of estimation of resistance level in lab conditions is based on discrimination doses, given to experimental samples of voles, i.e. 30 mg/kg of Etilfenacin in 3 days for anticoagulants of first generation, or single dose 1 mg/kg of Brodifacoum for second generation.