How long does chocolate take to kill mice?

They only spent 45 seconds on the 67% cocoa chocolate and 34 seconds at the 85% cocoa chocolate. The data for the time spent at each place seems to indicate that the higher the cocoa content, the less the mice like the chocolate.

Do house mice eat chocolate?

Although it is commonly believed that mice are attracted to cheese, they tend to prefer foods that are higher in carbohydrates. Chocolate may be more effective attractant for mice than cheese. However, house mice are indiscriminate and will consume any food source available to them.