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The toxicity of the anticoagulant brodifacoum to the field rodent species Microtus guentheri (Danford & Alston) and Meriones tristrami Thomas was tested in the laboratory. Brodifacoum 0.05 g kg -1 whole-wheat bait was offered to the animals without additional food. The LD 50 calculated for M. guendheri was 2-28 mg kg -1 body weight. Brodifacoum was found to be more toxic to M. tristrami; the LD 50 was c. 0.8-0.9 mg kg -1 body weight. The toxicity data served to plan the doses of bait to be broadcast in the field

Whole wheat grains impregnated with 0.02, 0.05 and 0.2% sodium fluoroacetate, and 2% zinc phosphide, were offered to series of single caged individuals of Microtus guentheri and Meriones tristrami. In most cases the sodium fluoroacetate treated baits were well accepted by both species. The acceptance of the zinc phosphide-treated bait was partial in all the series tested. The approximate LD50 ranges of sodium fluoroacetate are between 0.24 and 0.43 mg kg−1 for M. guentheri, and, perhaps, for the jirds too, and for zinc phosphide—between 32.6 and 58.8 mg kg−1 for M. tristrami, and a similar value, more or less, for M. guentheri.

The levant vole, Microtus guentheri (Danford et Alston), the only vole of major economic importance in the Middle East, is the species responsible for the often disastrous mice outbreaks known in this region since antiquity. Population cycles of vole populations and especially the impact of mass outbreaks have been less marked in recent times as a result of changes in cultivation methods, the introduction of new, less vulnerable crops (e.g. cotton) and the elimination of various former sources of infestation and spread of voles (drainage of swamps, regulation of rivers, etc.). On the other hand, new, permanent reservoirs of voles have been created; as, for instance, in alfalfa fields and orchards with permanent vegetation cover. Loss of crops in relation to expenditure of control in Israel is discussed. Various methods of control and rodenticides are reviewed. Organization of control operations, timing of control treatments as well as the need for forecasting impending vole outbreaks are emphasized.