I did some volunteer work at a vets office. But when I wrote about it, I explained it so that it tied into osteopathic medicine and my psychology major (animal beh stuff).
I think all clinical experience is beneficial, and susan hanson the director of admissions at COMP said that even if you volunteered at a hospital and only moved patients around you should have gotten some sort of experience from it. Thus, its cool to do chiro stuff I guess (although I think that type of practice is a bit extreme with their whole approach to medications n' stuff)...
Thats my opinion, but if you have a choice btwn shadowing someone else (MD or DO), then I'd go with the latter.