The sports section of your newspaper should have a racing section. Who's name pops up the most? Go to the track's website. They list the jockeys who work out of there. They probably list the trainers that house horses year round as well. When is the racing season over? What goes on at the track in the winter months?
You need work history that is going to separate you from the rest of the herd. Everyone's going to have great grades, they're going to have good interviews and glowing recommendations, they've all spent months traveling around the county with the local horse vet. What have you done or are going to do that will set you apart from the others? Of your dream schools, what are their premiere areas of study? I'd find a 4-6 week horseshoeing program. If nothing else, you can supplement your income with some trimming on the side.
Have you met with guidance counselors for the vet school? At a minimum, you've got to do everything on their ideal candidate list than expand it. Being fluent in Spanish is a nice bonus. Have you picked your large animal vet's brain? What contacts does s/he have? Even if it's traveling 100 miles once a week for something special, it could have tremendous payback. I'd find a 1st or 2nd year student, buy them a beer and pick their brain clean. (What did they do right in the application process, what did they do wrong, what preparation should they of had but didn't...)
Pie in the sky, and if money and real life didn't get in the way, I would jump on a plane, go to Africa and work on a rhino preserve. No one else could put that down on their application!