Unlike exposure to other toxins, many Agent Orange symptoms tend to take several years to decades to present, and can cause a host of health issues. Initial symptoms tend to include common side effects found with many other illnesses, as well as neurological and psychological problems.
Heavy breathing or panting. Most dogs will pant from time to time because they are stressed or excited, but when dogs pant for no apparent reason and the panting becomes excessive, this can definitely be a sign that a dog is experiencing pain.
Panting is a normal method of cooling down. All dogs pant sometimes -- it's just part of how their bodies work. But if your dog can't seem to control his heavy breathing, it could indicate a health problem. When his panting seems like it just won't stop, it's time to give your vet a call. Dogs sweat, but not as much as people do.