Veterinary medicine is the application of medical, diagnostic, and therapeutic principles to companion, domestic, exotic, wildlife, and production animals. An early interest in animal diseases is found in ancient Greek writings on medicine. Veterinary medicine began to achieve the stature of a science with the organization of the first school in the field in Lyons, France, in 1761. Veterinarians inducted the scrutiny of meat and milk to thwart the spread of tuberculosis. The development since World War II of live-virus and modified live-virus vaccines and of antibiotics, sulfonamides, and other biological products has brought about a marked change in veterinary medicine. An important innovation was the throng vaccination of poultry through sprays, dusts, and agents added to drinking water. Many animal diseases hitherto considered incurable can now be prevented or controlled by these new therapeutic agents, and this in turn has greatly enlarged the output of livestock and poultry products.

Veterinary medicine is informally as old as the human/animal bond but in recent years it has expanded exponentially because of the accessibility of advanced diagnostic and therapeutic techniques for most species. Animals often receive advanced medical, dental, and surgical care including insulin injections, root canals, hip replacements, cataract extractions, and pacemakers. Veterinarians aid in ensuring the quality, quantity, and security of food supplies by working to preserve the health of livestock and inspecting the meat itself. Veterinary scientists are very significant in chemical, biological, and pharmacological research. Clinical work with horses engrosses locomotory and orthopedic problems, digestive tract conditions and respiratory tract infections and disorders.