What characterizes first-generation anticoagulants?

First-generation anticoagulants are characterized by their requirement for multiple doses to achieve a lethal effect. This means that the bait needs to be consumed several times over a period for the rodent to accumulate a sufficient level of the active ingredient in their system to result in mortality. This extended dosing regime allows pests to ingest the bait over multiple feeding sessions while experiencing no immediate adverse effects, which can be particularly useful in baiting strategies where rodents may be wary of new food sources.

In contrast, single-dose rodenticides, which are more typical of second-generation anticoagulants, lead to quicker mortality after a single feeding. Immediate action is also characteristic of other classes of rodenticides, while effectiveness comparisons with second-generation anticoagulants highlight that first-generation anticoagulants usually require a more prolonged feeding strategy to be effective, rather than being inherently less effective overall.