A veterinarian who is trained in the USA earns a DVM (Doctorate of Veterinary Medicine) or a VMD (Veterinary Medical Doctor). This requires 4 years of veterinary medical school after 4 -5 years of college or university to earn a BS. There are some veterinary schools that will admit an application after only 2-3 year of undergraduate, though. All candidates must complete all of the vet school prerequisite classes--get excellent grades (GPA 3.5 or above) and GRE test scores-- and have good hands-on experience working with animals in a clinical or research setting.
Veterinarians who are trained in Canada, the UK, Australia and New Zealand go to vet school right out of secondary/high school. They attend veterinary school for 5 years and graduate with a BVetSci (bachelors of veterinary science). While Americans can (and do) attend these schools, Americans do so after obtaining a Bachelor's in Science at a state-side 4 yr college or university before attending these international schools.
Being a veterinarian takes as much school as being a medical doctor/physician. Many veterinarians even go on to complete a 1 year internship and 3-4 years of residency to specialize. And even once a veterinarian is out of school and practicing, she/he is still always learning by reading and attending conferences.
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