According to the American Veterinary Medical Association, the most common problems in dogs include failure to have dogs vaccinated, overpopulation caused by not spaying and neutering, and obesity. Dogs, like humans, can be protected against many serious and potentially fatal diseases caused by bacteria and viruses by getting vaccinated. Your veterinarian can give you advice concerning vaccination schedules, boosters, and any precautions to take when having your pet vaccinated. Overpopulation caused by failure to spay or neuter dogs causes many unwanted dogs that are put to sleep in animal shelters and pounds. In addition, dogs that have been or spayed or neutered tend to have lower rates of cancer and are less likely to roam since they don't need to pursue a mate. As dogs age, obesity may also become a problem. This extra weight stresses the dog's heart and kidneys, and increases the rate of diabetes and other serious health problems. For more information about common dog problems, please contact your veterinarian.