A new study reveals which U.S. cities are top dogs when it comes to pet health.

     The study, conducted by the Purina Pet Institute, ranked those cities that exemplify superior care, services and legislation for pets' health and well-being. It analyzed 30 different criteria ranging from veterinarian-to-pet ratios to incidence of obesity to rabies legislation. The top five Pet Healthiest Cities are:

1. Denver, Colo.
2. Oakland, Calif.
3. Portland, Ore.
4. Anaheim, Calif.
5. San Francisco, Calif.

     "This is the only comprehensive evaluation of factors that impact pets' health and affect their quality of life," said Dan Christian, DVM, executive director of the Purina Pet Institute. 
     The data revealed that pet obesity/body condition and preventative care are major issues. According to veterinarians surveyed, more than half of the nation's cats and dogs are overfed, which can lead to health problems. An unprecedented 14-year Purina study proved that feeding dogs properly throughout their lifetime to maintain ideal body condition can significantly extend their healthy years. 

Other significant results:

• Cats and dogs in San Francisco can claim clean lungs-the city has the lowest cigarette usage in the report and boasts zero annual ozone alert days.

• New York City and Oakland scored highest for percentage of dogs neutered (83 percent) and New York City tied with San Jose for highest percentage of cats neutered (86 percent).

• In the body condition category, New Orleans scored highest for percentage of dogs at ideal body weight (50 percent) and Nashville took top score for percentage of cats at ideal body weight (50 percent).

• Columbus, Ohio leads the country in the veterinarian-to-pet ratio with one veterinarian for every 745 pets.

While it is important to understand the environmental elements that affect a pet's health-such as the availability of qualified care, the prevalence of fleas or the requirements of licensing-there are many things individual pet owners can do to help improve their pet's health.

"The things pet owners control -obesity, preventative care, spaying and neutering-can literally add, or detract, healthy years from a pet's life," said Christian. 

Pet enthusiasts can log on to www.purina.com to find out more about the report and what they can do for their own pet's health. enne, a Border Collie from the Denver Dumb Friends League, shows off Purina's Pet Healthiest City award.