The Comparative efficacy of five rodenticides in the control of the gerbil Tatera Brantsii (A. Smith)

Abstract

The Highveld gerbil (Tatera brantsii), a pest of grain crops on the Transvaal Highveld and in the northern Orange Free State, was exposed to laboratory and field tests with anticoagulant and acute rodenticides. The tested rodenticides were chlorophacinone, diphacinone, warfarin with and without the addition of sulphaquinoxaline, zinc phosphide and pyriminyl. Efficacy was examined in the laboratory as regards mortality, lethal dosage, survival time and palatability. The possibility of sex differences in response to the rodenticides was also investigated. Of the anticoagulants, warfarin (0,025%) was less effective than diphacinone (0,005%) and chlorophacinone (0,005%). Sulphaquinoxaline did not significantly increase the efficacy of warfarin. Both acute poisons, zinc phosphide (2, 16%) and pyriminyl (0, 5%), were highly effective. In two field tests chlorophacinone was as effective as zinc phosphide in controlling T. brantsii. The reliability of a control method incorporating bait containers was confirmed.The susceptibility of T. brantsii to warfarin is discussed in relation to that of Rattus rattus, Rattus norvegicus, Mus musculus and Tatera indica.