Do vet colleges "practice" on animals?

KIMBERLYB5 asks: "My 9 year old lab has had a vomiting problem and after extensive tests, the vet wants to send her to a specialist for a procedure which I am afraid I won't be able to afford. There is a low income vet hospital in my state of Colorado but I make too much to qualify. Do vet colleges "practice" on animals? It's the only other option I can think of short of making payments on my credit card. Any ideas would be appreciated."