Blood Flashcards
What are the functions of Blood
- Carrier for nutrients, O2, CO2, Waste products, proteins and hormones.
- Thermoregulation
- Helps maintain normal fluid balance and pH
- Serves as a clinical diagnostic tool
- Rbc and Wbc counts
- Differential leukocyte count,
- Packed cell volume
- Hb concentration
- Blood chemistry
What type of proteins does the blood carry
albumin, fibrinogen, immunoglobulins
What are the components of blood
Blood is made up of plasma and formed elements (rbc,wbc, platelets)
Components of Plasma
Plasma contains 91-92% water and 8-9% solutes (proteins, lipids, and electrolytes);
What are the three layers of centrifuged blood
Centrifuged blood consists of three layers: Erythrocytes (45%, PCV or hematocrit,)
Buffy coat containing leukocytes and
Platelets (1%), and plasma
How to stain Blood Cells
Blood smear is dried, fixed in methanol, and stained with Romanowsky’s stains (Wright’s or Giemsa). Wright’s stain is a mixture of methylene blue (basic dye) and eosin (acidic dye).
What are Erythrocytes
Biconcave discs (elliptical in camels); central pallor, readily visible in humans and dogs, but less evident in other species
Size and number differ among species
What species has one of the largest Erythrocytes
Dogs
What species has one of the smallest Erythrocytes
Goats
What is anisocytosis
Red blood cells ( erythrocytes) varying in size.
Is common in most species
What is poikilocytosis
Variation in shape which is normally present in goats and deer
What is an example of poikilocytosis
Sickle cell due to inherited alteration in HB
What is rouleau formation and how does it effect horses, cats, dogs, pigs, and ruminants
Rouleau formation is the stacking of RBCs
It is common in horses and cats
Intermediate in dogs and pigs
Rare in ruminants
What are reticulocytes
Are Immature RBCs
Contain RNA and polysomes, seen as a reticular mesh when stained with methylene blue but not with Wright’s stain, 1-2% are normally seen in blood smears of dogs and cats but are not seen in horses and ruminants, increase in numbers in anemia in all species except horses.
What are Howell-Jolly Bodies
These are nuclear fragments and appear as basophilic inclusions within RBC, a few Howell bodies are normally seen in dogs and cats, but not in other species.
What are Heinz Bodies
These result from the oxidation of Hb and appear as refractile, light, pale areas in the Hb, especially in cats.
Average Life Span of RBC in Days: Cattle
159
Average Life Span of RBC in Days: Horse
145
Average Life Span of RBC in Days: Dog
120
Average Life Span of RBC in Days: Goat
125
Average Life Span of RBC in Days: Sheep
110
Average Life Span of RBC in Days: Cat
73
Average Life Span of RBC in Days: Pig
67
Average Life Span of RBC in Days: Bird
35
Leukocytes
Classified as polymorphonuclear granulocytes (neutrophils, eosinophils, basophils) and mononuclear agranulocytes (lymphocytes, monocytes); proportions of different populations of leukocytes vary among different species (see chart below); while neutrophils predominate in dogs and cats, they slightly exceed lymphocytes in horses; lymphocytes predominate in ruminants and lab animals.
Neutrophils account for what percent of total leukocyte in most animal species
Account for 40-70% of total leukocyte count in most animal species
What are neutrophils
First line of Defense
Phagocytic
12-15 micrometers in diameter; multilobed nuclei with an occasional Barr body in females
What do neutrophils contain
Contain pale azurophilic (or primary) granules (unspecific lysosomes and specific granules (specific lysosomes) in domestic species circulate for 6-14 h, emigrate to C.T., where they function for 48-96 h and then die or leave the body via the digestive epithelium; numbers increase in bacterial infections.
What are Heterophils
Note granules are large and reddish in rabbits, guinea pigs, and chickens; therefore, neutrophils are called heterophils in these species
Eosinophils account for what percent of total leukocyte in most animal species
Account for 2-8% of leukocyte count
What are Eosinophils
10-15 micrometers in diameter
bilobate nuclei; contain only specific granules, but they differ in morphology among species
The morphological difference of bilobate nulei’s specific granules based on species
horse: large, brick-red, mulberry-like shape
cattle: small, round, orange, and fill the cell
dog: few to many, vary in shape, rarely fill the cell
cat: rod shaped, grayish orange; microphage, phagocytose antigen-antibody complexes; numbers increase in parasitic infestations.
Basophils account for what percent of total leukocyte in most animal species
Account for 0-2% of leukocyte count
What are Basophils
10-15 micrometers in diameter; nuclear lobulation is obscured by basophilic granules, which are like mast cell’s granules in functions.
Monocyte account for what percent of total leukocyte in most animal species
Account for 3-8% of leukocyte count
What are monocytes
Largest blood leukocyte, agranular, 12-18 micrometers in diameter
Nucleus large and kidney shape, cytoplasm may show vacuoles in activated cells, emigrate to C.T. and differentiate into macrophages.
Lymphocytes account for what percent of total leukocyte in different animals
Account for 20-40% of leukocyte count in dogs, cats, and horses; 60-70% in ruminants, rats and mice; and 50-60% in pigs
What are Lymphocytes
Small (6-9 micrometers) and large (9-15 micrometers), T & B; small lymphocytes are prominent in dogs and cats, large lymphocytes in cows may have a vacuolated cytoplasm and can be confused with monocytes.
What are thrombocytes
Nucleated in fish, reptiles, and birds; anucleate in mammals; 2-3 micrometers in diameter; 9–12-day life span; formed from cytoplasmic processes of megakaryocytes;
What do thrombocytes cell contain
Cytoplasm surrounded by a cell membrane contains mitochondria, dense bodies, and alpha granules in the center and microfilaments and microtubules in the periphery;
What is the function of Thrombocytes
Function in blood clotting and sealing defects in the wall of blood vessels.
What is Hematopoiesis
Hematopoiesis is a continuous replacement of blood cells
Sites where Hematopoiesis occurs
Prenatal:
yolk sac
liver
spleen
lymph node
bone marrow.
Postnatal:
Bone marrow of all bones in young animals
sternum
vertebrae
ribs
skull
pelvis
and epiphyses of long bones in adult animals.
Stem cells involved in Hematopoiesis
Pluripotent
multipotent (lymphoid and myeloid)
and unipotent.
What is Myelopoiesis
Formation of all blood cells from one precursor cell, except lymphocytes.
Development of RBC
CFU-E (erythrocyte colony-forming unit, also known as mature progenitors), rubriblast (proerythroblast), prorubricyte (basophilic erythroblast), rubricyte (poychromatophilic erythroblast, also called normoblast), metarubricyte (orthochromatophilic erythroblast), reticulocyte, erythrocyte (no mitosis beyond rubricyte).
Maturational Changes during the development of RBC
Decrease in cell size, synthesis of Hb, loss of organelles, and condensation and loss of the nucleus.
What is erythropoietin
Erythropoietin plays an important role in RBC production.
Species variation in reticulocytes
Horse: do not find reticulocytes in the blood of healthy or anemic animals
Ruminants: do not find reticulocytes in healthy animals but is found in anemic animals
Dogs and cats: 1-2% of reticulocytes in the blood of healthy animals, increase in number in anemic animals (condition is called polychromasia in all animals).
Staining of reticulocytes
Cannot be identified conclusively in slides stained with both basic and acidic dyes (e.g., Wright’s or Romanowsky stain)
Conclusive identification can be made in slides stained with basic dyes only (e.g., methylene blue) because they contain polyribosomes, which, with basic dyes, are seen as basophilic strands.
Development of Granulocytes
CFU-G, myeloblast, promyelocyte, myelocyte, metamyelocyte, band cells, granulocytes (no mitosis beyond metamyelocyte). Maturational changes: synthesis of azurophilic granules (non-specific), formation of specific granules (neutral, acidic, or basic), decrease in cell size, increase in lobation and darkening of the nucleus, increase in the number of specific granules.
