Continued
As promised last week, let’s look at some more of the physical changes and decreased organ functions in the elderly pet.
Lung capacity decreased
Lungs also lose their elasticity during the aging process, and the ability of the lungs to oxygenate the blood may be decreased. Older dogs may be more prone to respiratory infections, and may tire more easily, because they can’t inhale enough oxygen with every breath. As the oxygen goes into the lungs, it reaches the red blood cells, which then take it to all the body’s organs via the blood circulatory system.
Decrease in kidney function
As animals age, the risk of kidney disease increases. This may be due to changes in the kidney itself, or result from the dysfunction of other organs such as the heart, which if not functioning properly, will decrease blood flow to the kidneys. Kidney function can be measured through laboratory tests on the blood and via an urinalysis. These tests can identify a kidney problem well before there are any physical signs of disease. The most frequent sign of kidney disease first noted by an owner would be an increase in water consumption and urination, but this generally does not occur until about 70% of the kidney function is lost. I had a professor who maintained that the first organ in the dog to lose its optimal function (during impending old age) is the kidney.
If the kidneys are not functioning normally, a special diet and doses of various medications may need to be introduced in order to assist the body in getting rid of the breakdown products.
Urinary incontinence and loss of housetraining
Urinary incontinence is involuntary or uncontrollable leaking of urine from the bladder. In older dogs, especially spayed females, small quantities or urine may leak from the urethra while the dog is resting or sleeping. Treatment for incontinence is usually not difficult. Your vet will advise you accordingly.
Some older dogs (those who are allowed to live indoors) who have been housetrained for years, may start having ‘accidents’. As with other behaviour problems in older dogs, there may be multiple causes for this change in behaviour. Any older dog with a house soiling problem should be examined by a veterinarian and the owner should be able to give a detailed history of the colour and amount of urine (or stool) passed, the frequency at which the dog needs to eliminate, changes in eating or drinking habits, the dog’s posture while eliminating, and whether the ‘accidents’ only occur when the owner is gone. Medical conditions contributing to the house soiling should be treated appropriately.
Prostate enlargement
When an unneutered male dog reaches 8 years of age, he has a greater than 80% chance of developing prostate disease, but it is rarely cancerous. In most cases, the prostate just enlarges. The prostate enlargement, however, can cause problems with urination or defecation. Older male dogs, especially those who are not neutered should have their prostate gland checked as part of the regular physical exam. The risk of prostate disease can be greatly reduced if the dog is neutered.
Decreased liver function
Although the liver has an incredible and unique way of regenerating itself when injured, the liver does age just like all other organs in the body. Its ability to detoxify the blood from harmful substances and produce numerous beneficial enzymes and proteins gradually decreases with age. I should mention however that sometimes the liver enzymes measured in a lab test could be abnormally elevated in an apparently normal animal. On the other hand, some animals with liver disease have normal levels of liver enzymes circulating in their blood. This makes interpretation of these liver test functions very difficult.
Changes in glandular function
Some glands tend to produce less hormones as they age, while other glands may produce more. Hormonal problems are a common disorder in many older dogs, and the propensity to develop a problem is sometimes linked to breed. The Golden Retriever, for example, has a much greater risk of developing hypothyroidism. Blood tests help to diagnose these diseases and many of them are treatable with the appropriate medications.
Changes in mammary glands
Female dogs may develop some hardening of the mammary glands due to the infiltration of fibrous tissue. Breast cancer in unspayed dogs is common. Mammary cancer is the single most common tumour of the female dog, and also the most malignant one. Older female dogs should have their mammary glands checked as part of the regular physical exam.
We’ll continue next week with the discussion on further physical changes in the elderly dog.
Please implement disease preventative measures (vaccinations, routine dewormings, monthly anti-Heartworm medication, etc) and adopt-a-pet from the GSPCA’s Animal Clinic and Shelter at Robb Street and Orange Walk, if you have the wherewithal to care well for the animals. Do not stray your unwanted pets, take them to the GSPCA’s Clinic and Shelter instead. If you do not wish your pet to have puppies or kittens, you may exploit the GSPCA’s free spay and neutering programme. If you see anyone being cruel to an animal, or if you need any technical information, please get in touch with the Clinic and Shelter by calling 226-4237.
