Appetite changes in your dog, especially dramatic ones, can be a cause for concern. Usually, appetite changes in themselves are a symptom of an underlying condition, be it physiological, environmental, or psychological.
Greatly increased appetite in dogs to the extent that your dog appears ravenous all the time (polyphagia) can be caused by a number of conditions. It’s important to determine whether the increased appetite is due to a disease or psychological factors. If the reason is a psychological, it’s likely a learned behavior which could lead to obesity. If the polyphagia is caused by disease, however, weight gain or weight loss will definitely come along with the appetite change. Increased appetite can be the result of diabetes onset or gastrointestinal absorption issues.
Dramatically decreased appetite or refusal to eat (anorexia) can lead to drastic weight loss. Dogs may avoid eating for a number of reasons. Autoimmune, bone, gastrointestinal, and endocrine conditions can cause dogs to stop eating due to pain, obstruction. Refusal to eat can also be psychological and rooted in an environmental change or other stress factor.
If you’ve witnessed an appetite change in your dog, talk to your vet and see the links below for more information.
Sources:
http://www.petmd.com/dog/conditions/digestive/c_multi_anorexia
http://www.petmd.com/dog/conditions/digestive/c_multi_polyphagia
