Patients and visitors are often surprised that I perform chiropractic adjustments on small animals and horses. It really shouldn't be surprising, all mammals have similar skeletal structures and nervous systems and all mammals can benefit from chiropractic adjustments. The reasons that chiropractic therapy works well in humans are the same reasons it works well on animals.
Any time a mammal sustains an injury, whether it is chronic or acute, there is a pain signal sent to the spinal cord from the injured area. This signal splits and part of it goes up to the brain to give you a sensation of pain. The other part of the signal gets magnified by a factor of 10 and goes back down to the injured tissue to tell it to make inflammatory biochemicals. These biochemicals cause the area to swell, become red, and more painful. Thus another pain signal is sent back to the spinal cord, gets magnified, and goes back down to the tissue to make more chemicals. This can become a self-perpetuating feedback cycle locking in a state of chronic low-level inflammation in the tissues of the body.
Chiropractic adjustments delivered by hand or via instrument stimulate a type of nerve ending called a mechanoreceptor. These mechanoreceptors tell the brain where your limbs are at in relation to the rest of your body. By stimulating the mechanoreceptors we can inhibit or slow down the pain signal coming from the injured tissue. This breaks the cycle of inflammation and allows the body to heal itself.
This is why chiropractic care worked so well in humans and why it works so well on animals. All mammals have the same type of neurochemical response to tissue injury and as a result all mammals can glean the same benefits from chiropractic care.
On a more practical note, I have found that animal adjustments helped tremendously with jumping and running problems in dogs and even large document dysplasia. It works wonderfully on the digestive system of cats and has even helped a poodle with bad gas problems. Many horses are adjusted before races because of the competitive advantage chiropractic treatments give. Working on animals is very rewarding because of the very fast results we see using chiropractic care.