Erythrocytes aka RBC’s. Laboratory Procedures. Hematopoietic System. Blood supplies cells with water, nutrients, electrolytes, and hormone. Removes waste products Mainly CO 2
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Erythrocytes aka RBC’s
Blood supplies cells with water, nutrients, electrolytes, and hormone.
Removes waste products
Cellular elements supply oxygen (RBC), protect against foreign organisms (WBC) and initiate coagulation (platelets).
Separates into three components:
Red Blood Cells (RBC’s)
White Blood Cells and platelets (buffy coat)
Bottom 1/3 to ½ of tube contains the heaviest of cellular material (the RBC’s).
To determine hematocrit, whole blood is centrifuged to pellet the red blood cells.
Plasma remains on the top of the red cells.
The fraction of blood that is packed is the hematocrit and is read as a percentage.
Normal values are usually 1/3 of the hematocrit.
Each hemoglobin molecule has 4 heme units attached to globulins.
Abnormal heme groups, cannot carry oxygen.
Carboxyhemaglobin- Hgb has a higher affinity for CO than O2.
Bright red blood
Methemoglobin- The Fe molecule is oxidized to Fe+3.
Blood becomes brown.
Tylenol toxicity in cats.
Carry oxygen to the tissues
Oxygen must be carried at enough pressure to permit rapid diffusion of oxygen.
The RBC is a vehicle for hemoglobin which is the carrier molecule for oxygen.
The sigmoid shape of curve is a result of the cooperative binding from the 4 hemoglobin molecules.
97% of oxygen transported from lungs to the tissues is carried in chemical combination with hemoglobin in RBC’s.
Production or Maturation of a RBC.
Only occurs in the bone marrow of normal adult animals.
Occurs in the spleen and liver of the fetus.
Maturation time usually takes 5 days.
Regulated by erythropoietin (EPO) which is increased in the presence of hypoxia.
In most species, the kidney is the sensor organ and major site of EPO.
No nucleus due to have to fold and squeeze through tight spaces.
Normocytes- cells look normal
Dog- 110 days
Cat- 70 days
Cow- 160 days
Horse- 145 days
Man- 120 days
Mouse- 30 days
Stem Cell → Rubriblast → Prorubricyte → Rubricyte →Metarubricyte→ Reticulocyte → RBC
Metarubricyte- nucleated RBC releases in severe anemia.
No more mitotic division takes place after this stage.
One rubriblast may give rise to as many as 8-32 RBC’s.
Also known as poikilocytes.
RBC’s with abnormal shape.
Formed as a result of shearing of the cell by fibrin strands. This occurs when red blood cells rapidly pass through microvasculature that is lined or meshed with strands.
They are observed in fragmentation hemolysis caused by DIC, vascular neoplasia, endocarditis, and possibly iron deficiency anemia.
Identified as the presence of many irregular membrane projections involving most RBC’s.
It is usually an artifact due to slow drying of the blood film.
Commonly observed in pig blood but can be seen in any species.
Cells have a spheroid shape instead of the usual biconcave disk shape.
Have reduced cell membrane and are hypochromatic.
Seen most frequently in autoimmune hemolytic anemia (AIHA).
Usually seen in dogs.
Two types of leptocytes observed mainly in dogs.
Represent cells with an increases membrane-to-volume ratio not specific to any disease.
The cell membrane is thin and flimsy.
artifacts when smears
made in high humidity
or if blown dry.
Can indicate liver disease or hemoglobinopathies.
Observed in RBC’s that contain abnormal aggregation of RNA.
Can be observed in cases of heavy metal poisoning with non-regenerative anemias or intense erythrogenesis in dogs, cats, and ruminants.
Nuclear remnants observed in young erythrocytes.
Often observed in cats and horses.
Can be seen in regenerative anemic animals.
Also may be seen with splenic disease or in an animal with the spleen removed.
Particles of denature hemoglobin protien.
They stain with new methylene blue and appear as colorless bumps with quick stain.
May be caused by oxidant drugs and chemicals. Also associated with onion toxicity in dogs!
Normal cat blood may have 2-3%.
Spleen recognizes as abnormal and starts to lyse the cells.
Non-nucleated cell containing RNA which can be easily seen when stained with methylene blue.
Hallmark of erythrocyte regenerative response.