The mechanism of consumption coagulopathy observed in cases of human envenomation by Bothrops jararaca is well established. However, this mechanism may vary according to the animal species studied. In order to study both the clinical and laboratory aspects of bothropic envenomation in dogs, a sublethal defibrinating dose of venom (100 micrograms/kg) was given intravenously. A coagulopathy similar to that observed in humans - including fibrinogen depletion, consumption of factors II, X, V and antithrombin III, and moderate thrombocytopenia - was observed. The presence of circulating activated platelets was also noted. Neutrophilic leukocytosis, lymphopenia, and monocytosis occurred at different times. Erythrocytic values remained normal in dogs treated with B. jararaca venom compared with those treated with saline alone. The erythrocyte sedimentation rate fell rapidly after venom administration and this fall was correlated logarithmically with fibrinogen concentration. Since the effects of envenomation in dogs is similar to that in humans, it was concluded that the dog can be used as a good animal model for studying human venom-induced coagulopathy.