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Demystifying the Avian CBC: The Complete Blood Count - Glossary

KrissyBy Jeannine Miesle, MA (Available for Professional Writing, Editing, Proofing)


Full Article: Demystifying the Avian CBC: The Complete Blood Count



  • Anemia: decrease in the number of red blood cells
  • Anisocytosis: the red blood cells are of unequal size and shape
  • Artifact: substances in the blood not naturally present
  • Basophils: a type of white blood cell that protects the body from infection by releasing histamines
  • Biliverdin: the green bile pigment that results from the breakdown of hemoglobin and is responsible for the greenish color seen in bruises; in birds it is seen in the droppings.
  • Buffy Coat: the layer of white cells that separates out at the junction between the red blood cells and the plasma after the sample is taken
  • Catalysts: a substance that causes or accelerates a chemical reaction without itself being affected.
    Coagulation: blood clotting
  • Colloidal osmotic pressure: pressure exerted by proteins in a blood vessel's plasma.
  • Cytoplasm: the complex of chemical compounds and structures within a plant or animal cell, excluding the nucleus.
  • Differential: the differential refers to the percentage of the different types of WBC’s; changes in normal range and cell characteristics indicate disease conditions.
  • Dyscrasias: diseases or disorders
  • Dysplasia: abnormal development
  • Electrophoresis: a process used in the separation of proteins and nucleic acids; it is used to study diseases in which there are altered (abnormal) serum and plasma proteins.
  • Enteropathies: diseases of the intestine
  • Eosinophils: A type of white blood cell that has coarse granules within its cytoplasm. Eosinophils are produced in the bone marrow. When a foreign substance enters the body, lymphocytes and neutrophils release substances to attract eosinophils and then release toxic substances to kill the invader. The number of eosinophils increases in response to allergens. Elevated eosinophil counts are also common in parasite diseases and asthma.
  • Erythrocytes: red blood cells
  • Fibrinogen: a protein in the plasma that is the blood-clotting factor
  • Granules/granulocytes: tiny spindle-shaped bodies in the white blood cell
  • Hematocrit: a blood test that measures the percentage of the volume of whole blood that is made up of red blood cells
  • Hemoconcentration: increased concentration of cells and solids in the blood, usually resulting from loss of fluid to the tissues
  • Hemolysis: the breakdown of RBC’s and subsequent release of red hemoglobin molecules into the plasma
  • Heparin: a drug that is used to prevent blood clots
  • Hepatic insufficiency: failure of the liver to function normally
  • Heterophils: a granular white blood cell or leukocyte; the avian equivalent of the mammalian neutrophil. They actively participate in inflammatory lesions and are phagocytic.
  • Heterophilia: increase in the number of heterophils
  • Hydrostatic pressure: pressure when fluids are at rest
  • Hypocalcemia: low serum calcium levels in the blood; this occurs when the concentration of free calcium ions in the blood falls below 4.0 mg/dl. Symptoms include neuromuscular irritability and numbness and tingling in their fingers and toes (neuropathy), although there are many more.
  • Hyperglycemia: high blood glucose level
  • Hypoglycemia: low blood glucose level
  • Icterus/Icteric, or jaundice: a yellowish pigmentation of the skin and eyes associated with liver disease
  • Immunoproteins: Blood proteins whose activities affect the functioning of the immune system.
  • Inanition: exhaustion due to starvation or chronic infection.
  • Leukocytes: white blood cells that provide the body’s defense as part of the immune system
  • Leukocytosis: an increase in the WBC count
  • Leukogram: a tabulation of the leukocytes present in a blood sample
  • Leukopenia: a decrease in the number of white blood cells
  • Lipemia: the presence of a fine emulsion of fat (lipids) in the blood
  • Lipemic artifact: fatty substances in the blood not naturally present
  • Lymphocytosis: all or most lymphocytes appear abnormal or immature. They attack infection, inflammation and bacteria
  • Lysis: breakdown of cells
  • Microhematocrit/microhematocrit tubes: a hematocrit determination done on an extremely small quantity of blood by use of a capillary tube and a high-speed centrifuge.
  • Mononuclear: having one nucleus
  • Mycosis/mycotic: fungal disease
  • Necrosis: the death of body tissue. It occurs when there is not enough blood flowing to the tissue, whether from injury, radiation, or chemicals.
  • Nephrotic syndrome: the damaged kidneys leak large amounts of protein in the urine
  • Neoplasia: the formation of an abnormal mass of tissue
  • Neutrophils: a granular leukocyte that fights against infection
  • Oocyte: the immature egg cell
  • Osteolysis/osteolytic: bone breakdown; dissolution or degeneration of bone tissue through disease; the reverse of ossification, or hardening of tissue to a bone-like state
  • Phagocyte: the cells that protect the body by ingesting (phagocytizing) harmful foreign particles, bacteria, and dead or dying cells
  • Phagocytize: To “eat” foreign material such as bacteria
  • Plasma: blood plasma; the fluid portion of the blood in which the particulate components (blood cells) are suspended
  • Platelets: cell cytoplasmic fragments that are responsible for blood clotting in mammals
  • Polychromasia: an abnormal color of the red blood cells; the RBC’s appear grayish-blue when examined on a blood smear slide under a microscope. Polychromasia occurs when RBC’s are released prematurely from the bone marrow, where they are produced. The premature release occurs in response to a certain type of hormone stimulation. This usually results from anemia or structural damage to the bone marrow from a variety of causes.
  • Polycythemia: abnormally high number of erythrocytes
  • Portal circulation: the regular movement of the blood through the heart and blood vessels
  • Psittacosis : an infectious bacterial disease in birds. This disease is zoonotic.
  • Reticulo-endothelial system: that part of the immune system that clears out abnormal and old cells, such as phagocytes, and deals with plasma cell dyscrasias.
  • Septicemia: bacteria in the blood (bacteremia) that often occurs with severe infections
  • Serum: the cell-free portion of the blood from which fibrinogen has been separated in the process of clotting
  • Suppuration: formation of pus
  • Thrombocytes: blood clotting cells in birds
  • Toxicosis: a disease due to poisoning
  • Vacuolated: containing tiny, bubble-like structures
  • Vacuoles: small cavities in the cytoplasm of a cell, bound by a single membrane, and containing water, food, or metabolic waste

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