Cage Efficacy Study of an Experimental Rodenticide Using Wild-Caught House Mice

The availability and effectiveness of rodenticides in the US and elsewhere has been changing for various reasons. As a result, new rodenticide formulations and active ingredients are being investigated in the US and other countries. We conducted a cage efficacy study of a paste bait containing 4.4% alphachloralose. A commercial product of this nature is manufactured and used in parts of Europe. While the formulation we tested was effective (100%) in a no-choice trial with wild caught house mice, it was not effective in two-choice trials (≤ 35%). We surmise that palatability may be an issue as the mice consumed very little of the paste bait. It was also clear that the paste bait is more effective at cooler temperatures. Future efforts could focus on identifying more palatable formulations