The family pet has never been better looked after in terms of disease prevention through vaccination and in its nutrition. As a result the domestic dog is now living longer and certain problems peculiar to old age are more frequently encountered by the veterinarian.
Enlarged prostate gland
Aged male dogs can develop an enlarged prostate gland. With increasing age the balance of the various breakdown products of the male hormone may change, and it is probably the long-term influence of one of these substances that causes a change in the normal cells that make up the prostate gland.
In the young animal the prostate gland is situated above the penis and is outside the abdominal cavity. As the animal ages the cells increase in size and the whole gland enlarges until it protrudes into the abdominal cavity below the rectum.
Further enlargement causes signs of discomfort when the dog has a full rectum and when it is straining to pass a bowel motion. Eventually the pain may become so intense that the dog avoids defecating and becomes constipated.
Another condition of the aged male dog is the anal adenoma. These are growths that arise in the tissues surrounding the anus. Certain breeds such as wire-haired fox terriers, beagles and spaniels seem most prone to develop anal adenomas.
The growths begin as small swellings, usually in the segment of the anus nearest the base of the tail. They are not painful and gradually increase in size until they can be the size of a large walnut.
When enlarged the skin surface is prone to ulcerate and may bleed profusely. Once ulcerated, infection occurs, producing a foul-smelling discharge, which attracts flies and which is intensely irritating to the dog.
As with enlargements of the prostate, these changes are associated with the male hormone balance. Treatment of prostatic enlargements and adenomas is similar and is aimed at reducing the secretion of male hormone, or testosterone.
In the past, castration was always performed and injections of female hormone, or oestrogens, were given. Enlargement of the prostate usually responds quite quickly to this combination, but where a very large anal adenoma has formed surgical removal is necessary.
Mammary tumors are commonly seen in aged female dogs that have not been desexed. These tumors vary considerably in size and shape, and can occur in more than one mammary gland. Many tumors are quite localized at first and are small, hard swellings in the substance of the gland.
Occasionally a softer and more rounded tumor may appear which increase rapidly in size. Mammary tumors are comparatively easily removed surgically before they become too large. Untreated, some tumors become so large that they reach the ground or hinder the movements of the hind legs. Not only is surgery more complicated in these cases, but there is a likelihood that secondary growths have spread to other vital organs.
As with the tumors affecting the male dog, early consultation with your veterinarian as soon as you notice any abnormalities will save your pet much discomfort and the need for extensive surgical intervention.