For the reasons katana posted, it’s much harder to be accepted into veterinary college than it is to be accepted into medical school. Some folks eventually go to medical school because they weren’t accepted into veterinary school. I’ve read that the average IQ of a veterinarian is higher than that of a medical doctor.
Per the Association of American Veterinary Medical Colleges (AAVMC), it is harder to get into veterinary medical school than it is to get into human medical school.
There are only 29 schools of veterinary medicine in North America while there are more than 160 schools for the study of human medicine. Each year there are approximately 21,000 applications for 2,500 – 2,600 slots for entering DVM students. It means that the schools are admitting the very best and brightest applicants they can get.