Although aging is irreversible, some of the infirmities of an older dog may in fact be due to disease and therefore correctable or preventable. It is important for any dog over six years of age to be examined thoroughly every six months.
In particular, you want regular blood work done on your dog. For example, if kidney function declines, you want to know so that you can switch to kidney-sensitive diets.
Older dogs are more complacent, less energetic and curious. They may be forgetful, and sleep more. Crankiness and irritability are common.
They are less tolerant of changes in the environment; in particular you may wish to have someone come by and check the dog at home rather than kennel it when you leave on vacation.
Older dogs in hospitals and kennels go off their feed, become overanxious, and bark frequently.
Loss of muscular tone and lessened activity may result in the neck and body becoming more bulky, but the legs more thin. Resistance to cold is impaired, so older dogs should always have a warm and draft-free bed. Arthritic dogs may need a padded surface to sleep on.
Moderate exercise helps keep the joints supple and should be encouraged, but not beyond your dog’s ability. Also, some conditions, such as heart trouble, may necessitate restraining your dog from exercise. Toenails will require more frequent trimming. Stiffening joints may make it more difficult for the dog to keep the genital and anal areas clean. The skin may dry out and require some care to keep it clean and less dry.
Loss of hearing and sight may occur. Tooth and gum disease is fairly common. Kidney failure and disease is more common (look for increased thirst and other symptoms of kidney failure). Incontinence (mostly in older spayed females, treatable with estrogen) may appear.
An older dog needs fewer calories. The food must be of high quality so that your dog still gets the nutrition it needs with fewer calories.
Geriatric Vestibular Disorder
Common in older dogs, apparently something happens neurologically in the connection between the brain and the inner ear (sometimes infection, sometimes inflammation). Very little is actually known about it, but it does tend to subside after about a day or so. Unfortunately, the dog is generally unable to eat or drink, as she is completely disoriented.
Dogs rarely show any enduring effects from such an episode other than sometimes their head leaning or tilting to one side.