Animal Blood Donors for Human Patients

To treat human patients, experts used blood from various animals. Both successful and unsuccessful cases were recorded. These sorts of blood transfusions, known as xenotransfusions, where blood was transfused from one species to another, were unpredictable, unreliable, and dangerous for patients, resulting in the deaths of many animals and humans. Experts who performed xenotransfusions did not understand that we have different blood groups and that the incompatibility of blood groups between the blood donor and patient leads to blood transfusion reactions, often fatal, because of the immune response, especially from different species. They basically used the blood of different animals just to see what would function better. Animals such as dogs, lambs, and calves were often dramatically weakened. Some of the experts who performed these blood transfusions were praised by the academic circle, while others were criticized. In successful cases, lower quantities of blood were transfused, which, by coincidence, led to the survival of patients with fewer blood transfusion reactions. The first expert who successfully transfused blood from one animal to another was Richard Lower (1665). Jean-Baptiste Denys (1667) and the surgeon Paul Emmerez were the first to successfully perform xenotransfusion from an animal to a human. Xenotransfusions, which proved to be dangerous for both the blood donor and the patient, were mostly abandoned in the late nineteenth century, with isolated cases in the twentieth century. It must be noted that human-to-human blood transfusions were performed in parallel with xenotransfusions.