CBC together: HCT, WBC, neutrophils and platelets
Separate red-cell proportion, white-cell totals and differentials, and platelet counts; then check specimen and smear notes.
Prepared by TengRip · Guide updated：2026-10-25
Not veterinarian-reviewed; a report-reading guide, not a diagnosis.
Read these findings together
These tests answer different questions. Read WBC with absolute differential counts and check whether an analyzer result needs smear confirmation. A normal total does not mean every cell type is normal.
This site does not list fixed normal values: reference ranges differ by analyzer and method, so always use the range printed on your report.
Work through your report
- Distinguish HCT, WBC and absolute differential counts from percentages.
- Look for platelet clumping, smear and sample-quality notes.
- Report observed bleeding, gum color, appetite, energy, fever and medicines.
| Test | Clues and limits | Related information |
|---|---|---|
| HCT / PCV | The proportion of blood occupied by red cells; hydration affects the result. | Reticulocytes, red-cell indices, proteins and clinical condition. |
| WBC | The total white-cell count; a normal total does not replace differential counts. | Absolute counts of cell types, blood smear, symptoms and medicines. |
| NEU | One white-cell type; read its absolute count rather than percentage alone. | WBC, other cell types, smear findings and symptoms. |
| PLT | Involved in hemostasis; clumping can cause an analyzer to underestimate the count. | Smear, clumping notes, repeat counts and coagulation tests when needed. |
Hematocrit / Packed Cell Volume (HCT / PCV)
The share of the blood made up of red blood cells and the main measure of anemia. Dehydration can make it falsely high, and IV fluids can make it lower.
What it measures
Hematocrit is the percentage of total blood volume taken up by red blood cells, which carry oxygen. A low value means anemia. PCV and HCT are measured differently but look at the same thing. Cats and dogs have different ranges, so use the range on your report.
What a high value may mean
The most common cause is dehydration: there is less water in the blood, so red cells make up a larger share, not because there are truly more of them. Rarely, red cells really are increased (polycythemia), which can be linked to low oxygen or certain tumors.
What a low value may mean
It means anemia, with three main causes: blood loss, destruction of red cells (hemolysis), and too little production by the bone marrow. IV fluids diluting the blood and sedatives or anesthetics (which relax the spleen so it holds more red cells) can also lower the value temporarily.
Usually read together with
Reticulocytes (to see whether the bone marrow is making new red cells), red cell indices, and total protein; urea and creatinine as well when judging dehydration.
When to follow up
If your cat has pale gums, low energy, or faster breathing along with a low hematocrit, see the vet promptly. For a mild drop, your vet will look for the cause with other tests and plan follow-up.
Section sources
White Blood Cells (WBC)
The total count of immune cells. Which type of white cell is changing matters more than the total, and a cat's count can rise temporarily when it is stressed at the clinic.
What it measures
White blood cells are the body's immune cells and include neutrophils, lymphocytes, and other types. A high or low total has many causes, and clinical interpretation guides suggest looking at which type is changing rather than the total alone; the differential count on your report does exactly that.
What a high value may mean
The three most common causes are stress (more steroid hormones in the body), excitement (driven by adrenaline, especially noticeable in cats), and inflammation. When a cat is stressed at the clinic, lymphocytes and neutrophils can rise temporarily, and kittens under six months naturally have higher lymphocytes. In inflammation or infection, it is mainly neutrophils that increase.
What a low value may mean
Possible causes include severe infection drawing large numbers of white cells into tissues; viral infections such as feline panleukopenia, feline leukemia virus (FeLV), and feline immunodeficiency virus (FIV); bone marrow problems; and some drugs (such as chemotherapy). Stress or steroids commonly lower lymphocytes.
Usually read together with
The differential count (neutrophils, lymphocytes, monocytes, eosinophils, and so on) and a blood smear review.
When to follow up
If white cells are clearly low, especially in an unvaccinated kitten that is also vomiting, has diarrhea, a fever, or very low energy, see the vet promptly. If the count is only mildly high and the cat's energy and appetite are normal, your vet may judge it to be stress-related and arrange a recheck if needed.
Section sources
Neutrophils (NEU)
A useful white-cell subset; a normal total WBC can coexist with low NEU.
Related clinical questions
Changes may involve inflammation, infection, medication or marrow supply.
Why this marker matters
Hormonal responses can raise counts. Low counts have several causes and do not identify a pathogen.
Interpretation limits
Read the absolute K/µL count, not just %NEU; use the total WBC and differential together.
Tests to read alongside it
Other absolute counts, smear morphology and immature cells, symptoms and medication history.
Questions at follow-up
Ask whether the reduction persists and needs a recheck. Seek timely care for fever, poor appetite or lethargy.
Section sources
Platelets (PLT)
Linked to bleeding risk; confirm feline low counts and check for clumps.
Related clinical questions
Platelets help stop bleeding. True reductions prompt assessment of bleeding and the underlying cause.
Why this marker matters
Clumps after collection may be missed by an analyzer, particularly in cats.
Interpretation limits
A low count proves neither clumping nor a specific disease. A normal PCT does not settle the question.
Tests to read alongside it
Blood smear estimate and clumps, repeat PLT, other blood cells and, when indicated, coagulation testing.
Questions at follow-up
Ask how the count was confirmed. Contact your vet promptly for bleeding or sudden severe weakness.
Section sources
Questions for the visit
- Do total and differential counts tell different stories?
- Has a low platelet count been checked?
- Which changes need prompt attention or planned follow-up?
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This site is for general reference only and is not a substitute for veterinary diagnosis. If your cat shows unusual signs, please see a vet promptly.