Susceptibility of bromadiolone anticoagulant rodenticide in two rodent species and its haematologic effect.

Susceptibility levels of the Norway rat, Rattus norvegicus and the roof rat, Rattus rattus to bromadiolone anticoagulant rodenticide by bioassay and biochemical methods were studied. Animals were trapped from Giza and Qualyobia Governorates in which the anticoagulant rodenticides were used to control rodents for long periods. Complete mortality was obtained for both species and sexes within standard no-choice feeding test period (4 days) indicating bromadiolone susceptibility. Treatment of rats with LD50 showed high prothrombin times which also indicate the susceptibility of the tested animals. In treated rats, bromadiolone caused significant decrease in the total erythrocytic counts and increase in the total leucocytic counts. In survivors, RBCs, WBCs approximately reached the control levels at day 43 post treatment. Also, treatment decreased neutrophils, eosinophils, basophils and monocytes but increased the lymphocytes in dead and survived animals more than in controls.