Every year Americans are getting heavier, not surprisingly so are our pets. The latest research indicates that half of all pets are overweight or obese. This closely mirrors the obesity epidemic in the human population.

This may explain why pet owners that were surveyed about pet body types (ideal, overweight, obese) thought their pets were at an ideal weight, even when they were obese.

Certain breeds of dogs have a disproportionately high incidence of obesity, indicating that genetics may be a contributing factor. Labrador retrievers, cocker spaniels, beagles, dachshunds, basset hounds, and pugs are more likely to be overweight or obese.

It is difficult to find predilections for obesity in a specific cat breed, but some surveys show that Persians are more prone to being overweight.

The bottom line is that our pets are becoming overweight for the same reasons we are: too much food and too little exercise.

Overweight pets are prone to a variety of health problems including diabetes, musculoskeletal problems (joint, ligament and tendon injuries), compromised immune function, cardiovascular disease, heat and exercise intolerance and pancreatitis. Obese dogs and cats are at a greater risk of anesthetic and surgical complications. Obese cats can suffer from skin problems, because they are unable to groom themselves properly.

To determine if your pet is overweight use these simple guidelines: you should feel the ribs, but not see them. Behind the last rib your pet should narrow some before widening a little at the hips. There should be a small tuck-in at the stomach. If your pet does not fit these guidelines he/she may be a little overweight. Start with a trip to your veterinarian for recommendations and to rule out any underlying medical conditions. Once your pet has received a clean bill of health you can institute life style changes to enhance weight loss and improve overall health.

Your veterinarian's recommendations will probably include daily exercise (a walk or a game of fetch), a diet change (a reduced calorie food), portion control (use a measuring cup and feed the exact amount recommended by your veterinarian), split portions (your pet may feel more satiated if you split the daily allotment into two equal portions), and feeding healthy treats (green beans, baby carrots and apple slices).

Once you and your veterinarian have decided on lifestyle changes be sure and stick to the program. Your pet did not gain the weight over night and should not be expected to lose it over night. You will probably find the program easier than you think, and your pet's life will be happier and longer because of your efforts.

Dr. Chris Rainey, a veterinarian at Animal Hospital of Orange Grove, Miss., encourages questions for this column. Write to South Mississippi Veterinary Medical Association, 20005 Pineville Road, Long Beach, MS 39560 and include a self-addressed stamped envelope.