Veterinary medicine is the branch of medicine that deals with the prevention, management, diagnosis, and treatment of disease, disorder, and injury in animals. Along with this, it deals with animal rearing, husbandry, breeding, research on nutrition, and product development. The scope of veterinary medicine is wide, covering all animal species, both domesticated and wild, with a wide range of conditions that can affect different species. Veterinary medicine is widely practiced, both with and without professional supervision. Professional care is most often led by a veterinary physician (also known as a veterinarian, veterinary surgeon, or "vet"), but also by paraveterinary workers, such as veterinary nurses or technicians. This can be augmented by other paraprofessionals with specific specialties, such as animal physiotherapy or dentistry, and species-relevant roles such as farriers. Veterinary science helps human health through the monitoring and control of zoonotic disease (infectious disease transmitted from nonhuman animals to humans), food safety, and through human applications via medical research. They also help to maintain food supply through livestock health monitoring and treatment, and mental health by keeping pets healthy and long-living. Veterinary scientists often collaborate with epidemiologists and other health or natural scientists, depending on type of work. Ethically, veterinarians are usually obliged to look after animal welfare. Veterinarians diagnose, treat, and help keep animals safe and healthy. History Premodern era Archeological evidence, in the form of a cow skull upon which trepanation had been performed, shows that people were performing veterinary procedures in the Neolithic (3400–3000 BCE). The Egyptian Papyrus of Kahun (Twelfth Dynasty of Egypt) is the first extant record of veterinary medicine. The Shalihotra Samhita, dating from the time of Ashoka, is an early Indian veterinary treatise. The edicts of Asoka read: "Everywhere King Piyadasi (Asoka) made two kinds of medicine (चिकित्सा) available, medicine for people, and medicine for animals. Where no healing herbs for people and animals were available, he ordered that they be bought and planted." Hippiatrica is a Byzantine compilation of hippiatrics, dated to the fifth or sixth century AD. The first attempts to organize and regulate the practice of treating animals tended to focus on horses because of their economic significance. In the Middle Ages, farriers combined their work in horseshoeing with the more general task of "horse doctoring". The Arabic tradition of Bayṭara, or Shiyāt al-Khayl, originates with the treatise of Ibn Akhī Hizām (fl. late ninth century). In 1356, the Lord Mayor