Today, it's a different situation; the potential is unlimited.
The profession of veterinary medicine began in the early 1800's when
people's horses and other animals (pigs, oxen, cattle, goats, dogs) became
ill or injured. These early animal doctors had little references to go by,
they assumed that the animal and the human organs were in the same locations
and in the same proportions. The veterinarians back then used very crude
tools and often times the animal would get an infection because the utensils
were not sterilized. Also, under operation the patients were given primitive
anesthesia that rarely eased the pain.