I never adjusted my dog out of concern that his anatomy is different than mine and yours. I recently completed the first of five modules in a veterinary chiropractic course and let me tell you I made the right decision by not adjusting him.
Let me give a short explanation why.
First of all this course goes really in depth in dog and horse anatomy (we even work with and are tested on cadavers). Let me tell you that although a spine may look like a spine the anatomy of the joints, muscles and other tissues as well as the stress placed upon them is completely different across different animals and are especially unique when compared to us humans. So needless to say, applying human techniques to animal spines is like throwing darts blindfolded, you might get lucky and hit the board once but by no means is it a detailed systematic approach.
Secondly the health conditions, repetitive strains and traumas animals can face are not the same as what humans deal with. The obvious is that animals are not vertical structures, they walk on four legs and the result is they deal with shear forces as opposed to compressive forces in their spines which can affect their spines differently. Also the conditions that can present although similar to some human conditions can present differently. Finally some breeds are highly predisposed to health conditions that if adjusted by a chiropractor could potentially be life threatening to the dog. In essence if a human chiropractor applies human techniques to animals it can not only be dangerous to the animal but it is very naive for the chiropractor to think that it would be effective in the first place.
I hope that puts into perspective the difference animals and humans, as well as the type of training that goes into becoming certified to work with animal chiropractic in Canada. If you are looking for an animal chiropractor, I will be licensed early 2018. Also I need work with and present case studies on animals. If you have a dog or horse that you would like to get checked, please reach out to me and we will work together to help them.