BLOOD TEST AND CHEMISTRY PROFILES
JUST WHAT DO THEY TELL US?
We all know that every dog
should receive a thorough veterinary examination once a year.
As part of this yearly exam, most of us are advised to obtain a blood
count and serum chemistry profile. We
are told that these tests will provide invaluable information about OUR dog
for the future. That when your dog
is in a healthy state, the blood tests will establish normal levels that your
veterinarian can refer back to, should your dog get become ill in the future.
This month I will discuss the “Normal Complete Blood Count Values”, what the
“numbers” mean and how to know if your dog is within the
A complete blood count (CBC) is
taken to indicate the quantity and quality of cells in the blood.
Every laboratory that does
blood work will have its own level of ranges of what they consider normal.
These values will vary and are dependent upon the particular laboratory
equipment being used. Normal
readings are established by taking a certain number of dogs and analyzing their
blood and then averaging it out. You
should ask your veterinarian how the norms are established for the laboratory
that he uses. If you are using blood
chemistry to work out a diagnosis, do not use several different laboratories.
Stay with one for consistent results.
If you work with your
veterinarian on a yearly basis, you can establish the normal levels of blood
chemistry for your dog. Establishing
norms prior to any health problems is just “good” preventative medicine.
Below is a chart that shows
“NORMAL” Complete Blood Count Values and an explanation of the
values. Keep in mind, however, that
there may be a variation in the “norm” depending on the laboratory used.
5.5 - 8.5 X 100,000/L
37 - 55 percent
Hemoglobin (Hb) g/L
6.0 - 17 x 1000/L
Neutrophils (seg) x 1000/ul
0.01-1.25 Monocytes x 1000/ul
RBC-RED BLOOD CELL COUNT—Red
blood cells transport oxygen and carbon dioxide between the lungs and the body
tissues. They are produced in the
bone marrow and are under the control of chemicals that are secreted by the
kidneys. The red blood cells have
various component parts:
PVC (PACK CELL VOLUME/HEMATOCRIT)
is the most commonly used expression of red cell numbers and is measured as a
percentage of blood composed of red blood cells.
“DECREASED” levels of RBC
or PCV is commonly termed “anemia” and have three (3) basic cause
Reduced bone marrow production that can be from an
iron deficiency, a vitamin B12 deficiency, or chronic kidney or liver disease;
Loss of blood from the body such as external or
internal hemorrhage, or parasites;
Destruction within the body called hemolytic anemia
(breaking down of red blood cells).
“INCREASED” levels of RBC
or PCV are usually the result of dehydration.
It can also be the result of the bone marrow over-producing red blood
cells, but this is rare. Over-use of
vitamin/mineral products can also cause increases in hematocrit levels.
HEMOGLOBIN (Hb) is the essential oxygen carrier of
the blood. It is found within the
red blood cells and is responsible for the red color of the blood.
It is essentially equivalent to the PVC.
“DECREASED” levels indicate
the presence of hemorrhage and anemia.
“INCREASED” levels indicate
a higher than normal concentration of red blood cells.
RETICULOCYTES are immature red blood cells that
have been released from the bone marrow prematurely.
“DECREASED” count, if
associated with chronic anemia, indicates a lowered red blood cell production by
the bone marrow.
“INCREASED” count is
associated with chronic hemorrhage or hemolytic anemia (destruction of RBCs).
PLATELET COUNT test indicates the blood clotting
ability of the dog. Platelets, also
called thrombocytes, are derived from the bone marrow.
“DECREASD” numbers of
platelets occur in bone marrow depression, autoimmune hemolytic anemia, systemic
lupus (a blood clotting disorder), severe hemorrhage or intravascular
“INCREASED” numbers of
platelets occur sometimes when there is a fracture, a blood vessel injury or if
the bone marrow is overproducing (cancer).
WBC is the total number of white blood
cells. WBC’s are often called
leucocytes. There are different
kinds of white blood cells and the figure shown on the chart is reached by
combining the total of these various kinds of white cells together.
The different kinds of cells are called neutophils, neutrophil bands,
lymphocytes, eosinophils, monocytes and basophils.
“DECREASED” levels of WBCs
may indicate developmental or metabolic disorders, an overwhelming infection,
especially from viruses, or drug and chemical poisoning.
“INCREASED” levels of WBCs
can be seen in infections, especially bacterial in nature, as well as emotional
upsets and blood disorders.
NEUTROPHILS are white blood cells that go to work
in the face of inflammation. They
consume foreign material and destroy bacteria.
“DECREASED” numbers of
neutropils might indicate viral infection, starvation, drug reactions, or an
overwhelming bacterial infection.
“INCREASED” numbers would
indicate a local bacterial infection and inflammation, stress, tissue
destruction such as abscesses or tumors, or the use of steroid drugs.
NEUTROPHIL BANDS are immature neutrophils that are
prematurely released from the bone marrow when there is an immediate need for
them, such as at the site of the inflammation.
“INCREASED” numbers of
bands indicate that the bone marrow has the infection or it has the inflammation
under control. If the band cells are
greater than 10 percent of the mature neutrophils, and the total WBC is normal
or low, then it would show that the bone marries is losing the battle.
LYMPHOCYTES function along with the immune
system. They recognize antigens
(enzymes, toxins or foreign substances) and produce antibodies (protein
substances) that fight the antigens.
“DECREASED” numbers are
seen from stress, steroid use or cancer chemotherapy drugs.
“INCREASED” numbers result
from a strong stimulus to the immune system such as chronic inflammation,
recovery from acute infections and under active adrenal glands (Addison’s
EOSINOPHILS are the detoxifiers of histamine.
Histamine is a substance released by the body whenever tissue is damaged.
“DECREASED” numbers occur
with stress, steroid use, or an overactive adrenal gland (Cushing’s Disease).
“INCREASED” numbers occur
during an allergic reaction to something in the environment, or when parasites
are in the system or with an under active adrenal gland (Addison’s Disease).
MONOCYTES are single cells that are immature
forms of macrophages. Macrophages
are the cells that “eat” foreign bodies and cellular debris.
“DECREASED” numbers are not
regarded as “important”.
“INCREASED” numbers occur
with chronic fungus infections, dying tissue, chronic inflammatory and immune
diseases. They also increase with a
stress reaction from using steroid medications and Cushing’s Disease.
BASOPHILS contain both histamine and heparin.
Heparin is a blood clotting inhibitor.
These cells start the inflammatory response after the body is injured.
Basophils are not commonly found on the blood smear of dogs.
“DECREASED” numbers can be
an indicator of an under active thyroid.
“INCREASED” numbers of
these cells are associated with high levels of fact in the blood, heartworm
disease, Cushing’s Disease, thrombus formation (blood clot within the blood
vessels) and ulcerative colitis.
Next month I will discuss the
blood chemistry profile (Serum Chemistry Profile) and what those numbers mean.
As always, the above information is based on my personal research.
References include: http://www.thepetcenter.com/pha/cp.html
As always, comments welcome!
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