My dog is going on nine years old and is slowing down quite a bit. How can I make him more comfortable, and what is the best way to take care of an older dog?

Dogs experience many of the same infirmities that humans do in old age. "Failing eyesight and hearing, arthritis, kidney and liver disorders, periodontal disease, constipation, tumors and heart problems are common," states Jeanne Hall in a booklet from Ralston Purina, "Caring for the Older Dog.""By adjusting to your elderly dog's day-to-day needs as they change, you can prevent some serious disorders and delay others, as well as protect it from excessive discomfort," says Hall. Dog owners should be prepared to make adjustments in the following areas:

Temperature - Old dogs that are ill should never be expected to sleep outdoors, even if they have done so all their lives. If your dog is old and well, and has slept outdoors, provide an insulated, watertight house that is free of drafts. Make sure it has a flap over the door to keep out winter's chill. Change the bedding once a week to keep it clean and free of parasites. Straw or newspaper is better than blankets, which may retain moisture and freeze during cold weather.

Exercise - Some older dogs grow obese because they continue to consume the same amounts of food, but their metabolisms are slower and they exercise less frequently. Don't push your older dog to run, jump and play as vigorously as it once did - but don't stop exercising it, either.

Diet - Carrying excess weight puts a strain on an older dog's heart, lungs, muscles and joints, and can dramatically reduce its life expectancy. Because the activity level and metabolism have dropped, your dog may need less food to stay trim.

Safety - Don't let your older dog roam or take it off the leash when taking a walk. The dog's sight and hearing aren't as sharp as they once were, and the animal's reaction time will be slower - factors that make cars, fighting dogs and bicyclists more dangerous.