Field Evaluation Of Palatability Of Extruded And Wax Block Rodenticides Against Rattus Norvegicus

Abstract:
Control of Rattus norvegicus in Brazil is frequently made by applying wax blocks and, more recently, with extruded blocks containing a second generation anticoagulant a.i., where wax blocks have shown low attractiveness. We conducted two field studies to evaluate the attractiveness of a wax block (Klerat® Wax Block 20 g) and an extruded block (TalonXT® 20 g), both with the active ingredient Brodicafoum at 0.005% concentration. They were compared with three other rodenticides commercially available in Brazil. The four blocks of each type were placed adjacent to each other in bait stations inside a basement near grain storage. During the period of February to April 2013, the wax blocks were replaced 8 times. Nine evaluations showed that Klerat consumption was higher and represented 46.50% of all rodenticide consumption, while consumption of first alternative bait (Brodifacoum 0.005%) represented just 24.38%; the second alternative bait (Brodifacoum 0.005%) represented 18.77% and the third alternative bait (Difethialone 0.0025%) represented just 10.35%. During the period of August to October 2013, the extruded blocks were replaced 9 times. Ten evaluations showed that TalonXT consumption was higher and represented 80.20% of all rodenticide consumption, while consumption of first alternative bait (Brodifacoum 0.005%) represented just 11.25%. Consumption of the second alternative bait (Difethialone 0.0025%) represented just 8.17% and the consumption of the third alternative bait (Bromadiolone 0.005%) represented just 0.38%. Klerat® and Talon® showed better palatability and this information is valuable when designing an effective rodent control program