I’ll be slightly provocative and say that vets like to be called “doctor” (Dr) because they want to be on an equal footing to human doctors. It is a courtesy and a convenient title for veterinarians. Normally the title “Dr” follows attaining a PhD. But human doctors and veterinarians don’t always have PhDs. Some do, it just depends on whether they studied for a PhD at sometime or other as well as their doctoral or veterinary degrees.
The reason why doctors i.e. human doctors are called doctors is because of the verb “to doctor”. It’s a verb that is used outside of medicine which means to change something. For example, somebody might say that “I doctored the letter”. This means that the person changed the letter in a surreptitious way.
So the word “doctor” means to change something and it applies to medicine in that a doctor changes a person’s function to improve them healthwise.
It’s ironic that veterinarians describe themselves as “veterinary surgeons”. If a person is a human surgeon they like to call themselves “Mr” in their professional sphere. Therefore in a strict sense veterinarians should have the title “Mr” but that doesn’t work because more than half of veterinarians in the UK are females. I am sure it is a similar percentage in many other countries.
In some countries, like Australia, osteopaths and chiropractors are allowed to call themselves doctor. It all comes down to convention and what people accept. In the UK they had a poll among their veterinarians as to whether they should style themselves doctor because internationally the title is used by a lot by veterinarians. Therefore it saves confusion when for example a British veterinarian is working abroad.
When veterinarians use the title “Dr” it is a courtesy title and it does not necessarily reflect academic attainment. Although, as mentioned, it might do because a veterinarian may have a PhD in some other area of science or even in the arts. But when you refer to a veterinarian as Dr Smith, it does not imply that Mr Smith has a PhD.
P.S. It is perhaps imprecise to shorten “veterinarian” to “vet” because as you know the word “vet” is also used to describe military veterans who have retired from the military. Therefore on the Internet Google might be confused if you are searching for information about veterinarians using the shortened version “vet”.
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