An apparent case of brodifacoum toxicosis in a whelping dog

A 7-y-old Weimaraner bitch was presented to emergency service after 3 h of active labor with no puppies produced. Hemoabdomen and hemothorax were present at the time of surgery; prothrombin time (PT) and activated partial thromboplastin time (aPTT) were both found to be within normal ranges. Surgical cesarean section was performed; 4 dead puppies and 5 live puppies were delivered. Because hemostasis was difficult to achieve, a hysterectomy was performed; however, the dog died as the operation was being completed. At autopsy, the pleural cavity contained 1.5 L of unclotted blood; the peritoneal cavity was relatively normal, and no obvious hemorrhage was associated with the surgical sites. All 4 dead fetuses were opened, and their pleural cavities were filled with unclotted blood. An anticoagulant screen was performed, and brodifacoum was identified in the liver of the bitch. This case is unusual in that the PT and aPTT were within reference intervals, but brodifacoum was present in sufficient amounts to potentially result in this dog bleeding to death, and also is suspected to have crossed the placenta and caused hemothorax and death in 4 of 9 puppies in utero.