Autopsies deal only with human cause of death while necropsies involve the same process, but performed on an animal. In both an autopsy and necropsy, a body is examined to determine the cause of death.
The two terms are often used interchangeably and are believed to mean the same thing. While both processes serve to identify cause of death, they differ greatly in their implication. To perform an autopsy, a forensic pathologist must have undergone specialized training and obtained an M.D., the qualification necessary to become a practicing doctor in the United States of America. On the other hand, a necropsy is performed by a veterinarian who is an expert in animal anatomy and physiology, unlike a medically trained forensic pathologist.