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

544 •DOG OWNER’S HOME VETERINARY HANDBOOK
Prevention: Spaying a female before the first heat cycle reduces her risk of
breast cancer to less than 1 percent. If she is spayed after one heat period, her
risk is still only 8 percent. After two heat cycles, however, there is no reduction
in risk.
It is important to examine the mammary glands of unspayed bitches every
month, starting at 6 years of age or younger. If you feel a suspicious lump or
swelling, take the dog to your veterinarian at once. Experience shows that
many owners procrastinate for several months hoping that a lump will go
away. Thus, the opportunity to cure many mammary cancers is lost.
Leukemia
Leukemia is a cancer involving the blood elements in the bone marrow,
including the lymphocytes, monocytes, platelets, eosinophils, basophils, and
erythrocytes. All of these cells can give rise to cell-specific leukemias. For
example, lymphoid leukemia is a malignant transformation of the lymphocytes,
or white blood cells. Leukemia is further subdivided into acute and
chronic stages. Both stages are relatively rare in dogs.
Leukemia generally occurs in middle-aged dogs. Signs are nonspecific and
include fever, loss of appetite, weight loss, and sometimes anemia with pale
mucous membranes. Usually the disease is discovered when blood tests are
drawn to diagnose these symptoms. Leukemic cells may or may not be found
circulating in the blood. A bone marrow biopsy confirms the diagnosis.
Treatment: Leukemia is treated with anti-cancer drugs. Chemotherapy
does not cure leukemia, but may put the disease into remission for several
months or longer. Dogs with chronic leukemia have a better prognosis than
those with acute leukemia.