Several people responded to your other thread with some good nuggets about wildlife med:
How do I become an all animal vet?
A couple of older threads---this topic is discussed regularly and you can find many more with the Search function:
Wildlife Vet?
About Wildlife Medicine
Long story short: 2-4 years of undergrad doing vet school pre-reqs (which can vary slightly depending on the school) + 4 years DVM +/- 1+ years of post-DVM internship +/- 3-4 years residency (especially if you're wanting to work somewhere AZA accredited or at large zoos)
Reaching these milestones is competitive to varying degrees. Most pre-vets who are seriously interested in wildlife, zoo, and exotics work very hard to gain experience and maintain contacts in those fields; in such a small sect of the profession, knowing people and getting your name out there is extremely important when it comes time to pursue any post-DVM training and search for jobs. The salaries for wildlife and zoo are also very low considering the amount of education and training needed, especially during internship and residency if you elect to go through with those.
Many, many students nowadays go through vet school wanting to work with zoo or wildlife species but few of them actually make that a reality. It's a very difficult field to break into.
If wildlife is your primary interest, I would start working on accruing experience in the field NOW. Not only do you need hours for vet school applications, but you need an accurate frame of reference for what the field is actually like before you dive into it headfirst. Get out there and see if it is something you would even enjoy doing first.