Questions Flashcards
Neutrophils make up the majority of white blood cells in the circulation of dog and cat. What percentage?
70 %
30% are lymphocytes.
The other white blood cells are present in very small numbers.
How are neutrophils identified?
The large nucleus and numerous granules in the cytoplasm. The neutrophil nucleus consists of 2-5 lobes and appears segmented. Neutrophils are short lived and usually only survive in circulation for 1-4 days.
What is the neutrophils function?
They attacks infectious agents.
They phagocytose foreign material and release enzymes to digest any infecting organism. They are the predominant cells present in pus. The presence of immature neutrophils(also called band cells) and increased number of neutrophils suggest an infection.
What are the two types of lymphocytes?
T lymphocytes produced in the thymus
B lymphocytes produced by the bone marrow.
These are very important cells in the immune response.
Lymphocytes are larger than rbc.
The cytoplasm of the cell can be stained pale blue for examination.
Life span can vary from few days to few years.
What is the eosinophil function?
The nucleus generally has 2 lobes and cytoplasm containing granules.
Following romanowsky staining these granules appear bright red.
Main function is to fight parasitic infection but can also be seen in allergic reactions.
Describe basophil.
In dogs and cats they make up only 1% of wbc and are difficult to locate in normal blood.
Nucleus is separated into separate lobes and cytoplasm contains granules.
Granules appear blue when stained.
They are involved in inflammation and allergic reactions.
What are monocytes?
They are the largest type of wbc.
They have an oval or horseshoe shaped nucleus.
They are produced in the bone marrow.
They travel to the connective tissue of the skin, spleen, brain and other organs.
When they enter the connective tissue they are known as macrophages.
They are responsible for phagocytosis.
What is haemopoeisis?
The process by which wbc are produced from bone marrow in the long bones, pelvis, sternum and skull in young animal. And in the epiphyses of long bones, pelvis, sternum and skull of adult animals.
The spleen and liver can also take part in production where there is an increased demand for blood cells.
What is erythropoiesis?
The process where rbc are produced from the bone marrow. The process is stimulated by erythropoietin produced by the kidney.
As rbc develop, the nucleus condensed and is present until the developing rbc becomes a reticulocyte.
In aneamia increased numbers of nucleated rbc and reticulocytes can be seen in circulation.
What is the most predominant blood cell?
Rbc or erythrocytes are circular in shape with a depression in the centre. This gives a disc like appearance. Allowing a greater transfer of oxygen.
Rbc contain haemoglobin which is needed to carry o2.
When they die or become damaged they are removed from the circulation by the spleen.
Platelets are..
Very small cells that have no nucleus. They originate from a giant cell known as a megakaryocyte, located in the bone marrow.
Once in circulation, they have a lifespan of approx 10s days. They are involved in the clotting mechanism and are also known as thrombycytes.
Red blood cells in horses have a tendency to form..
Rouleaux. (stacks)
What unusual wbc are found in a rabbit?
Pseudo eosinophil, which is really a neutrophil but when stained looks more like an eosinophil.
What unusual wbc are found in the Guinea pig?
Kurloff cell.
This is a circulating mononuclear cell with a large inclusion (Kurloff body) commonly seen in mature Guinea pigs during gestation.
There tend to be more lymphocytes than neutrophils in small mammals.
In a bird neutrophils are known as
Heterophils.
They are nucleated and oval in shape. They have a lobed nucleus and cigar shaped granules in cytoplasm which appear red when stained.
They are the first line of defence during an infection.
The avian platelet is also nucleated.
