Field trials of warfarin and brodifacoum wax block baits for the control of the rice field rat,Rattus argentiventerin peninsular Malaysia∗

Abstract

Abstract Replicated trials, in which 0.05% warfarin and 0.005% brodifacoum were used to control rice field rats, are described. In the first trial, 15 g wax blocks containing the poisons were applied, in 20–24 ha rice field plots, once a week for four weeks or twice a week for four weeks or once a week for 8 weeks. In the second trial, 5 g wax blocks were applied once a week for four weeks. In both trials baiting commenced at the time of transplanting, and the effectiveness of treatments was measured by mortality estimates, derived from pre‐ and post‐treatment census baiting in treated and reference plots and by damage reduction in post‐treatment damage assessments. Both poisons were equally effective when applied as 15 g blocks giving, on average, between 81% and 82% control, but gave significantly better control (87%) when applied twice a week rather than once (79%). However, when 5 g blocks were used, the more toxic poison, brodifacoum, gave 80% control compared with only 56% with warfarin. Tiller cutt...