What type of rodenticides decreases the clotting ability of blood and is effective after one feeding?

The type of rodenticides that decreases the clotting ability of blood and is effective after one feeding is a single feeding anticoagulant. This class of rodenticides works by inhibiting vitamin K, which is essential for the synthesis of clotting factors in the blood. As a result, after consuming a lethal dose of the bait, the rodent's ability to form clots is impaired, leading to internal bleeding and eventual death.

Single feeding anticoagulants are designed to be effective with just one feeding, making them efficient for pest control. Their quick action reduces the chances of the rodent becoming bait-shy, as they do not require multiple feedings to achieve lethality.

In contrast, multiple feeding anticoagulants require several feedings over a period of time before they produce lethality, and thus are not suitable for this specific question. Non-anticoagulant rodenticides operate through different mechanisms, such as causing dehydration or disrupting metabolism, and trapping agents do not involve chemical ingestion at all.