In my line of work (polo) most grooms have training and experience and it is part of their duties. Definitely the massage end, and there are those good in chiropractic work everywhere.
I have heard of other disciplines using chiropractors and massage therapists extensively.
I will recommend that if you go to a school, go to one that actually teaches anatomy and physiology along with massage technique. But those that have that background are able to get better results and address actual conditions or injuries, in my experience.