I was research oriented in college and I've just spent the last year doing vaccine research at NIH. I had SA and LA clinical experience to put on my app, but I'm certain that it's the stuff I've been doing in the lab that set me apart during the application cycle. So, to answer your question, YES research is a great thing to have on your app because it sets you apart from other applicants! If you can get published or go to professional conferences with a poster or something, that looks even more impressive. Plus, if you think about it, all of these vet schools have faculty or other grad students doing research because it is very lucrative and a good research program = solid funding and support.
So, even if you're not looking to do lab animal medicine, having a vet degree and going into research is extremely valuable. I've heard from my colleagues that research institutions are always looking to hire research oriented vets.