When you first bring home that animated ball of fur, your puppy's antics bring you no end to laughter.

There are challenges in training him; your patience is tried as he goes through the destructive chewing phase. But within a few months you have a dog that fits your idea of the perfect companion. You enjoy many years of fun adventures and glorious outings together. But at some point around the age of seven years, your beloved friend will start to show signs of aging. The exact age varies from breed to breed and dog to dog; larger dogs usually show signs of age earlier than smaller dogs do, but the years catch up to all of them. Here are some signs to watch for and some ways to help your old friend out:

Obesity

Many owners neglect to change their dog's diet as he ages. A young, strong adult dog burns off more calories in a day than an older dog. Feed a diet formulated for senior dogs. Make sure you're giving him the appropriate amount of food. Remember that table scraps and treats add to the overall calories your dog is taking in, and adjust his food accordingly. Modify your dog's exercise routine, but keep him active enough to keep his weight down. A slim dog will be healthier and more active through his golden years.

Arthritis

Arthritis is a common ailment in older dogs affecting joints. If your dog is having trouble getting up or down, takes longer to get moving and moves slower, and no longer jumps up or takes the stairs as often, take him to the vet. There's no cure for arthritis, but your vet can help you find treatments and therapies that can ease the discomfort. Keeping your dog at an ideal weight can help ease arthritis as well.

Blindness

Many older dogs develop cataracts. Their eyes may appear cloudy or opaque. If caught early enough, cataracts can be removed and your dog's eyesight can be improved. If your dog does go blind, help him out. Leave the furniture in the same place so he learns to avoid it. Try to limit the number of steps he has to navigate or carry him up and down stairs if possible.

Diabetes

Diabetes is another illness that can plague older dogs. Obesity can play a part in diabetes as well. If your dog starts drinking excessively, needing to go out more often, loses weight without a change in feeding, or has an abnormal appetite, take him to the vet. Diabetes can be fatal if not treated.

Heart Disease

Older dogs often develop a condition that affects the function of their heart valves, which can lead to heart failure. Some signs to watch for are difficulty breathing, lethargy, a chronic cough, excessive panting or fainting. This is another condition that can be treated by your vet but is fatal when untreated.

Dementia

Dogs can develop canine Cognitive Dysfunction Syndrome (CDS), a form of dementia much like Alzheimer's in humans. Doggy dementia can cause your dog to forget his housebreaking and other training, his name, or he may not recognize you. He may spend long periods staring into space, pacing or walking in circles.

Other Issues

Older dogs can also suffer from hearing loss, thyroid disease, and cancer. Make regular visits to your vet so treatment can be started as early as possible. You may want to consider taking your dog for wellness check ups every six months instead of annually. Your aging friend is just as loyal and loving as ever. Let him slow down some, keep an eye on how he's feeling, and the two of you will enjoy his twilight years more fully.