Dog Owner's Home Veterinary Handbook.pdf - Mr. Walnuts

the ejaculate when a male dog mates. This fluid provides nutrients and assists
in the sperm’s movement. The three conditions that cause prostatic enlargement
are benign prostatic hyperplasia, prostatitis, and cancer of the prostate.
The diagnosis of prostate enlargement is made by digital rectal examination,
during which the size, position, and firmness of the prostate gland is
assessed. Ultrasonography provides additional information and may be helpful
in guiding a needle into the prostate to obtain a biopsy—a procedure indicated
when cancer is suspected.
BENIGN PROSTATIC HYPERPLASIA
This is an increase in the size of the prostate gland. The disease is hormonedependent
and is influenced by testosterone. Benign prostatic hyperplasia
begins in sexually intact males at about 5 years of age and progresses as the
dog grows older. Thus, older dogs are more likely to have symptoms.
As the prostate enlarges, it gradually expands backward and may eventually
obstruct the rectum, causing constipation and straining while defecating
(see Anorectal Obstructions, page 287). The feces may appear flat or ribbonlike.
Defecation is difficult. Fecal impactions are common.
Rarely, the prostate pushes forward and presses on the urethra, causing
straining during urination. Blood in the urine can be a sign of benign prostatic
hyperplasia.
Treatment: Treatment is not necessary unless the dog has symptoms.
Neutering eliminates the stimulus for prostatic enlargement and is the treatment
of choice for dogs who are not intended for breeding. A significant
decrease in the size of the prostate gland occurs shortly after neutering.
An alternative to neutering is to administer megestrol acetate (Megace), a
synthetic derivative of progesterone. Megace decreases the size of the prostate
without impairing fertility, but long-term use may cause a dog to develop diabetes
mellitus or adrenal problems. Note that estrogens, because of their
potentially serious side effects, are no longer recommended for treating benign
prostatic hyperplasia.
PROSTATITIS
THE URINARY SYSTEM • 419
Prostatitis is a bacterial infection of the prostate gland, usually preceded by a
bout of cystitis. Signs of acute prostatitis are fever, depression, vomiting, diarrhea,
and painful urination. The dog may have an arched back or a tucked-up
abdomen. Blood-tinged or purulent secretions may drip from the prepuce.
The prostate gland is enlarged, swollen, and tender.
The disease can become chronic, with periodic flare-ups. Chronic prostatitis
is a significant cause of male infertility.