When they asked if I had questions, I said something to the effect of....
"Before I ask my questions, I just wanted to thank you for this opportunity...." and I did a very short little bit on understanding the demands and realities of becoming a vet, asserting I wanted to attend this school, and I thanked them for considering me for the upcoming class.
It wasn't rehersed or anything, but I thought it'd be a nice way to say, hey I really, really want to go here. They seemed quite pleased, and I got accepted so it certainly didn't hurt. I doubt too many other people closed assertively like that, so I do think it made me stand out a little.
Then I asked about campus safety (my campus had a few incidents recently), how many students applied and got into residencies, and some questions about the radiology department (one of my interests).