Chiropractic derives from two words-cheir (hand) and Praktos (done): done by hand. Chiropractic was first discovered/developed/performed in America by DD Palmer in 1895. DD Palmer known as the father of chiropractic published an article as early as 1899 describing the benefits of spinal manipulation in horses. There are lots of photographic evidence of him and early Chiro founders manipulating a whole range of animals. 

Chiropractic involves using your hands to apply a very specific, high velocity, low amplitude adjustment to restore optimal movement and function to the body be it human or animal. This in turn allows us to restore functional movement back to the joints or stimulate the nerves within or around the joint. When we palpate or feel the joints/muscles we are feeling for a decrease or increase of motion within the joint or a hardness or softness to the overlying tissue eg muscles. It takes many hours/days/weeks/years to hone these skills. (When I was at college an exercise to help with this was trying to palpate a hair through numerous sheafs of paper!) Chiropractic is a very safe form of treatment for many different ailments but like you or I, animals may feel a bit tender after an adjustment. This is just the body adjusting to what we have done. All adjustments are performed within the normal physical range of motion of the joint.

Chiropractic should never replace conventional medicine but is a great tool to work alongside to help restore optimum health, in any individual no matter what species, size or age!