OSU interviews are pretty personalized. For in-staters, we interviewed with two people, either people form the admission's office, professors in the vet school, vets practicing in the area or retired vets. Interviews are with both people at once and are roughly 1/2 hour. Mine was close to 45 minutes though, I guess because the two retired vets interviewing me were having a good time making me sweat. I got asked a lot about Avian flu, my different experiences and what I did at each of them, why vet school and why now. How much vets make and how am I going to pay for school and pay back loans. Medical questions pertained to my experiences. For instance, I was talking about working in the emergency room and seeing some cases of bloat and I got asked what it was, how you treat it, likely outcome, and medical term (GDV). I also had some sport's equine experience so I was questioned about hourse breeds and racing. Oh and they usually always ask the difference between animal welfare and animal rights.
But basically each set of interviewers have free reign to ask whatever they want. Oh and if you get Dr. Saunders she likes to make you name 10 beef cattle, dairy cattle, swine, or whatever else strikes her fancy.
Good luck and have fun!