Composition of Blood
Red blood cells
White blood cells
Platelets
Plasma
Hemoglobin
Allows red blood cells to transport oxygen to tissues
Contains iron molecules that bind to oxygen molecules
what gives blood its red color
One of three proteins in the blood
Bilirubin
Created by hemoglobin when red blood cells are destroyed or lysed
a catabolic byproduct
yellow pigment
Can show up in bruises or on tissue membranes
Methemoglobinemia
A condition when animals consume acetaminophen
large amounts of hemoglobin will be replaced by methemoglobin
Methemoglobin will bind to oxygen, not releasing it to the cells
Causes internal hypoxia
Icterus or Jaundice
used to describe yellow membranes
large amounts of bilirubin in the bloodstream
Plasma
The liquid portion of whole blood
Contains all three proteins
Serum
The liquid portion of clotted blood
secreted from an open wound
3 major proteins found in the blood
Albumin
Globulins
Fibrinogen
Albumin
Maintains oncotic pressure (blood pressure)
Globulins
The major component of the immunity system
Fibrinogen
Used to clot blood
Blood functions
Transportation
Regulation
Defense
Blood Transportation
carries oxygen to tissues
carries carbon dioxide to the lungs
carries hormones for the endocrine system
Blood Regulation
Regulates internal temperatures and pH levels
Blood Defense
White blood cells defend against foreign invaders
Platelets prevent excessive hemorrhaging
Types of Blood cells
Erythrocytes
Leukocytes
Thrombocytes
Erythrocyte structure
Red blood cells Make-up the majority of the blood's cells Anucleated Biconcave disk shape Devoid of organelles Carry fluid and hemoglobin
Erythrocyte function
To act as an oxygen carrier
Anemia
Reduced oxygen-carrying capability
Causes of Anemia
Iron-deficiency Hemolytic Hemorrhagic Aplastic Morphological Erythropoietin-deficiency
Iron deficiency
Without iron, hemoglobin cannot bind to oxygen
This can be congenital or metabolic
Hemolytic
Caused by the destruction of red blood cells
Hemorrhagic
Caused by bleeding
Removes blood from the circulatory system
Aplastic
Occurs when the bone marrow cannot make enough
Autoimmune or neoplastic
Morphological
Rare in animals
Can be caused by any alterations to the shape of erythrocytes
Erythropoietin-deficiency
occurs during end-stage chronic renal failure
Hypoxia
Lack of oxygen in the tissues
Leads to Cyanosis
Erythropoiesis
production of red blood cells
occurs within the spongy bone of bone tissue and is stimulated in response to hypoxia
Erythrocytes Life Cycle
Mature red blood cells are released from the bone marrow
Immature red blood cells may be released early into the bloodstream either from anemia or bone marrow dysfunction
Erythrocytes End of Life Cycle
68 days for cats
110 days for dogs
broken down and recycled by fixed macrophages in the spleen and liver
Leukocytes
Neutrophils-granulocyte Lymphocytes-agranulocyte Monocytes-agranulocyte Eosinophils-granulocyte Basophils-granulocyte
Diapedesis
The act of a cell passing through a capillary wall in response to a stimulant
Chemotaxis
The movement of a cell towards a chemical stimulant
Neutrophils
Most common white blood cells Active immune response via phagocytosis First responder for foreign invaders Engulf microorganisms nuclei segment with age
Band neutrophil
A neutrophil has a nucleus with no visible segments
Released prematurely
Lymphocytes
Heavily involved with the immune system
The smallest type of leukocyte
The nucleus normally takes up the majority of the intracellular space
Four types
Monocytes
Largest of all white blood cells
Contain visible cytoplasmic vacuoles
Devoid of granules
Monocyte function
- Active immune response via phagocytosis
- The second responder during an infection
- Partners with neutrophils
- Active longer than neutrophils
- Become macrophages when they enter tissues
- A blood panel displaying high amounts of monocytes indicate a chronic infection
Eosinophils
Anti-inflammatory response
Assists with the immune system
Attacks many parasites with its granules
Named after the red color of the solution that it absorbs during staining
Basophils
Anticoagulation and allergic reaction response
Granules contain histamine and heparin
Gets its name from the blue stain of the granules
rarest of all leukocytes
Histamine
Used to initiate an allergic reaction
Heparin
Used as an anticoagulant
Leukopoiesis
Production of white blood cells
Thrombocytes
Platelets
Serves as the body’s immediate response to hemorrhaging
Lack a nucleus so not true cells
Composed of fragments that bud off a megakaryocyte
Smaller than red blood cells
Thrombocytes Function
Achieves homeostasis by forming a clot that plugs an open wound
Prevents more hemorrhaging
Clotting cascade
A wound is introduced to a blood vessel causing bleeding
Receptors on the endothelial membrane activate the clotting cascade
Thrombin is released and converts fibrinogen into fibrin
Fibrin polymerized into a mesh that forms a clot
Thrombus
A blood clot formed in the bloodstream
Embolism
The blockage of a blood vessel by any object
Thromboembolism
The blockage of a blood vessel by a blood clot
Thrombocytopenia
Having a thrombocyte count less than normal
Can be caused by an autoimmune response, neoplastic or severe blood loss
leads to clotting disorders
Petechiae
Pin-point and numerous
Ecchymosis
Larger and covers a wider area
Thrombocyte count
175,000 to 500,00 in dogs and cats
Cyanosis
Lack of oxygen causes mucous membranes and other thin tissues to appear blue