Technical information for veterinarians

Aging in dogs

Aging dogs and cats experience the same ailments as people do when they grow older. The clinical symptoms of aging are easy to recognize. The dog or cat may lose the lustrous coat of youth (and have grey hairs), develop brittle nails and appear slow and stiff due to arthritic conditions. Less easy to identify are intrinsic changes.

Intrinsic changes associated with aging in dogs may include reduction of vision, deafness, sclerosis (hardening of the internal tissues), build-up of metabolic waste, swelling in the extremities; inflammatory bowel disease, diverticular disease, degenerative joint disease (osteoarthritis), osteoporosis, hypertension, cardiovascular disease, thrombosis, cachexia, breathing difficulties and kidney problems.

Note Thanks to a better understanding of how people age and why, the aging process can, to a degree, be slowed down. The same should be achievable for companion animals.

Genetic predisposition, lifestyle and previous trauma are contributing factors to the rate and extent that a companion animal ages. dog owners should be encouraged to seek your advice regarding aging in their dog, and should be apprised of what to watch for, and examinations/supplements/lifestyle changes that are beneficial in identifying and managing developing diseases/conditions.

Signs of aging in dogs

The various breeds of cat and dog experience aging differently. In some animals (toy breeds of dogs, for example), changes in the heart are common, whereas in cats, the kidneys may be one of the first organs to show signs of aging.

Nutritional needs

As dogs age, their metabolism slows and their caloric need decreases. (This decrease is normally in the region of 20 percent.) Since the older dog’s activity level usually declines as well, his energy needs are reduced by a further 10 to 20 percent. This can lead to obesity in senior dogs. Senior dogs also require an increase in fiber and a decrease in fat. Nutritional supplements are often advised, particularly if the dog has a limited appetite.

Unlike dogs, a cat’s need for energy stays relatively consistent throughout adulthood. While obesity is one of the main health problems of middle-aged cats, older cats tend to lose some of that fat. Some studies suggest that senior cats do not digest/absorb fat as well as when they were younger.

Skin and coat changes

s with people, older dogs and cats may start to grey. The coat may become thinner and lose its lustre, however, this may be a sign of nutritional deficiency rather than old age. Dog and cat owners should be encouraged to groom their dogs more, with special attention being paid to the anal area. This will be a good opportunity to check for sores and tumours. Dry skin may be a problem for older dogs. Fatty acid supplements should help alleviate the condition, while improving the lustre of the coat.

Vision: Ophthalmic examinations should be in the physical examinations of senior dogs and cats. Older dogs frequently develop nuclear sclerosis, where the lens of the eye is clouded. Despite this, the dog’s vision is not impaired. Cataracts commonly occur in senior dogs and cats, and some may develop glaucoma.

Certain breeds are predisposed to glaucoma including:


  • Afghan
  • Akita
  • Alaskan Malamute
  • Basset Hound
  • Beagle
  • Border Collie
  • Boston Terrier
  • Bouvier des Flanders
  • Chihuahua
  • Cocker Spaniel
  • Cairn Terrier
  • Corgi,
  • Cardigan Welsh Corgi,
  • Pembroke Welsh Chow
  • Dachshund
  • Dalmatian
  • Dandie Dinmont
  • English Springer Spaniel
  • Fox Terrier, wire haired
  • Fox Terrier, smooth coated
  • Maltese
  • Manchester Terrier
  • Miniature Pinscher
  • Norwegian Terrier
  • Norwich Terrier
  • Poodle
  • Saluki
  • Schnauzer, Giant
  • Scottish Terrier
  • Sealyham Terrier
  • Siberian Husky
  • Samoyed
  • Shih Tzu
  • Skye Terrier
  • Tibetan Terrier
  • Welsh Terrier
  • Welsh Springer Spaniel
  • West Highland White Terrier
  • Whipdog


  • Persian
  • Siamese
  • Some Domestic Shorthairs.

Pet owners should be encouraged to seek your professional advice immediately if their pet appears to be experiencing a change in vision.


Losing the ability to hear clearly is common among older companion animals. Slight hearing loss is hard to assess in dogs and cats. More often, hearing loss will progress to an advanced degree before the owner becomes aware of it. Oftentimes, dog owners view the symptoms of hearing loss as negative behavioural changes. A dog may snarl and snap when approached, or a cat may turn and claw. The dog owner will not realize that this behaviour is simply because the dog had no idea that someone was approaching and reacted from instinct.

Another sign that a dog is suffering from hearing loss is failing to obey commands. The owner may view this as the dog acting out, but in fact, he simply cannot hear them. The same applies to cats that suddenly do not come when called.

Changes in urinary habits

Urinary incontinence is a common problem in older dogs, particularly bitches, and cats. dog owners should be made aware that senior animals likely don’t know that they are passing urine and/or couldn’t prevent this happening if they were aware. Senior animals should never be scolded for inappropriate passing of urine.

Changes in eating habits

Older dogs are more likely to develop tooth and gum disease. This can often be painful, causing a loss of desire to eat. Waning activity levels will also cause a reduction in apdogite.

Decreased mobility

Many senior dogs experience a reduction in mobility as they age. This is often due to arthritis. Large breeds of dog, dogs with an inherited tendency to develop intervertebral (IV) disc disease (bassets, dachshunds), and dogs/cats that have experienced a previous trauma are more likely to develop arthritis.

Arthritis can range from mild to debilitating — preventing dogs from carrying on with their regular routines. While older dogs may have problems moving well, they should always be encouraged to exercise to reduce loss of muscle tone and mass.

Decreased heart function

As dogs and cats age, the heart begins to lose efficiency. Mitral valve problems are particularly common in smaller breeds. Cats frequently develop cardiomyopathy. Diagnostic tests such as radiographs, EKG, and echocardiograms are effective in diagnosing heart disease.

Decreased immune function

As dogs and cats age, their immune systems fail to function as effectively. Infectious diseases are therefore more common. dog owners should be encouraged to keep up their dog’s vaccination schedule.

Can aging be delayed?

Aging in dogs is a normal degenerative process of cell and tissue structure and function associated with dehydration and lack of elasticity in superficial and deep tissue. However, the processes leading to dehydration and lack of elasticity can be addressed and, to an extent, delayed.

Bioflavonoids (plant-based, antioxidant substances with the power to protect plant and animal tissues), have been shown in many scientific studies to help the tissues maintain their youthful structure. Antioxidants from green tea (Camellia sinensis) and grapes (Vitis vinifera) have been shown to have particularly beneficial effects and may be employed preventively or therapeutically to help repair damaged tissues. Nutricol® (available to veterinarians as Recovery®SA, is a proprietary formulation containing both these ingredients.*

Other substances that can help aging companion animals are glucosamine hydrochloride (similar to glucosamine sulfate but having more positive benefits on the joints), and MSM (methyl sulfonyl methane) which also helps restore joint tissues. Since large dog breeds begin to age at age seven or thereabouts, smaller breeds at age 10 and cats at around age 12, you may wish to recommend these substances as part of the diet as a preventive measure.

Refer your clients to Anti-Aging Tips for Your dog