I have applied to Wisconsin's veterinary program 3 times over 4 years. I'm in-state and wait-listed at #10. Over the past years I've learned a lot about their process, and I want to post what I know because I wish I would have known this when I first got into college to better prepare. This is information that I have received from faculty, staff, fellow students and from discussion forums, I can't guarantee that the information is going to be 100% accurate for years to come, I just know what they have been doing for the past few years.
First off, don't let anyone tell you that they'll care more about your experience or passion than grades. The first step the admissions committee takes is to establish rankings, which are determined by an equation that takes into account your 3 GPAs (cumulative, required coursework, and last 30 credits), and your GRE scores. This is used together with the past 5 years of vet students to predict what a student's GPA will be after graduating from vet school. i.e. they won't take someone who - based on their predictions - will flunk out. This raw ranking counts for 60% of your application. Next, two faculty members that sit on the admission committee (which normally has some amount of rotation each year), review the complete application and grade it based on a rubric for the other 40%. As one of these faculty members said candidly to me last year, they basically take the top 50 IS and then get together and argue about the last 10.
This is the point at which you really need to be someone who stands out. In my experience, being honest, and getting a lot of insight from friends, family, colleagues, advisers has been very helpful in helping me to illustrate my "story." I've heard from several people that they don't take emphasizing large animal care very seriously because a lot of people think that's what they're supposed to write about. One of the worst things you can do is to leave an area blank. Something got screwed up with my supplemental last year and it didn't save two of my responses. When I went in for my review they said it looked lazy and they wouldn't take someone who wasn't going to put the effort in to complete it. Another thing that you don't want to do is to just save your essay from previous years and resubmit it. They told me that some people do that every year and committee members tend to recognize these, and then they say the same thing: "lazy, not gonna happen."
Based on the forums I've read, it sounds like the out-of-state and in-state pools are separate. For out-of-state, if you don't make certain cut-offs, they don't even look at your application (I really wish someone would have told me that), but I don't know exactly what those are so I won't speculate. They did tell me that for IS applicants they look at your application no matter what. In the past, there have been 20 spots for OOS and 60 for IS, but it sounds like they expanded the OOS pool to 27. Last year the IS alternate list took up to #15.
There are no interviews at Wisconsin, and you have to rely on snail mail (for IS anyway).
One final insight that I've found at least a little heartening: you have years and years to work as a veterinarian. It's absolutely brutal not getting in, but if you keep trying then you'll get in eventually. Even if you don't get in until you're 40, you still have 25-30 years as a vet. No rush. But still painful. I hope this has helped someone, I'll check back if anyone wants clarification or has questions that I might be able to help with.