Unveiling the potency of ready-to-use brodifacoum blocks in lesser bandicoot rats: exploring toxicity, blood clotting factors, and organ histology.

Abstract

The present study unveiled the effectiveness of ready-to-use brodifacoum blocks (0.005%) against the prevalent field rat species in southeast Asia, Bandicota bengalensis. Brodifacoum, a more potent second-generation anticoagulant, offers a solution for managing rodents resistant to other anticoagulants of its class. Male and female bandicoot rats caught wild were exposed to brodifacoum for 1, 2, and 3days in both the no-choice and bi-choice tests. The observations included mortality rates, impact on body weight, food consumption, blood clotting factors, organ weights, and histological changes. Results indicated 100% mortality within 2-3days in the no-choice tests, and 50.00%-83.33% mortality in the bi-choice tests within 5 to 8days. The median lethal feeding periods were determined to be 2.10 and 2.33days for male and female rats, respectively. Toxicity symptoms included bleeding from the nose, gums, and feet. While no significant effects were observed on body weight or organ weights, food consumption decreased notably in no-choice tests. Additionally, significant increases in prothrombin time and activated partial thromboplastin time were noted 24h post-treatment in the no-choice tests, with post-treatment international normalized ratios of 9.45-14.20 and 1.52-3.03 in the no-choice and the bi-choice tests, respectively. Histological analysis revealed mild to severe necrotic changes in the liver and kidneys after brodifacoum treatment. Overall, this study underscores the potential of ready-to-use brodifacoum blocks as an effective tool for rodent population control, offering a viable alternative to other second-generation anticoagulant rodenticides.