1. Circulatory System

2. Objectives State the structures that make up the circulatory system
Describe the functions of the circulatory system
Identify and describe the function of the various types of blood cells
Describe blood flow through the heart
Objectives

3. Circulatory system is essential for life and involves the heart, blood, arteries, veins and capillaries. The functions of the circulatory system include oxygen flow, blood circulation, and transport of nutrients, waste removal and the movement of hormones
Introduction

4. Blood Circulatory system begins with blood flow
Blood is composed of 40% cells and 60% plasma
Plasma- formed of various proteins
Proteins include albumin, globulin and fibrinogen
Albumin: draws water into bloodstream and helps in providing hydration to the body
Globulins: provide antibodies to help prevent disease
Fibrinogen: aids in clotting blood
Blood

5. Hematology: study of blood and an essential practice in the vet facility
Some blood testing procedures require the blood tube to be spun at high speeds using a piece of equipment called a centrifuge
Uses speed to separate blood elements, causing the cells to separate the liquid portion of the blood known as serum
Serum: liquid portion of the blood sample that is used to analyze chemistry values to determine the functions of the body’s organs
Blood Continued

6. Blood Continued Blood is made up of red cells and white cells
Red Blood Cells (RBCs) known as erythrocytes and most abundant blood cell in the body
Main function is to transport oxygen throughout the body
Produced in bone marrow through the process of erythropoiesis
Constantly be produced and replaced
Hemoglobin: main component that allows for oxygen transport and produces iron that allows RBCs to be replicated or continue being produced
Blood Continued

7. Blood Continued White blood cells (WBCs) known as leukocytes
Body’s main defense against infection
Five types found in an animal’s bloodstream
Neutrophils: most commonly seen WBCs and destroy any microorganisms in the tissues
Lymphocytes: make up largest part of bloodstream and aid in immune functions and help fight diseases by producing antibodies in the blood
Eosinophils: fight against allergic reactions, help control inflammation and help prevent parasite infections within the body
Monocytes: largest WBC and help the neutrophils by removing organisms, dead cells and foreign particles
As age they become macrophages, which eat and destroy organisms at different locations
Basophils: cells are involved with allergic reactions and they have a segmented nucleus with granules that stain very dark
Granules contain histamine which is released during an allergic reaction
Blood Continued

8. Blood Continued Another type of cell found within blood is a platelet
Aid in clotting time of blood after an injury occurs to a blood vessel, causing the vessel to constrict
Attach to the vessel site and plug hole and help decrease bleeding
AKA thrombocytes
Not enough are formed in blood: anemia
Causes RBC count to be low and doesn’t allow them to replenish
Autoimmune disease may occur when animal’s RBCs are destroyed by its immune system
Blood Continued

9. Organ with four chambers and is located in the chest between two lungs
Wall made of thick cardiac muscle called myocardium
Thin inner layer of muscle called endocardium
Outside thin covering of the myocardium is the epicardium
Outside of the heart lined by sac called pericardium
Thin membrane that covers, protects, and maintains the beating action of the heart
The Heart

10. Blood flows throughout the body allowing for systemic circulation and oxygenation
Delivers nutrients to the entire body
Veins located through body and are vessels that carry blood to the heart
Arteries are vessels located throughout that carry blood away from the heart
Have thick muscular walls and can be used to determine pulse
Pulse is heart rate which is the pumping action of blood through the heart
Blood Flow

11. Heart Sounds Heart sounds created by closing of valves
Can be heard through the use of a stethoscope
Sounds can be controlled by a pacemaker of the heart known as the SA node
First heart sounds known as the lub is created by the closure of the AV valves
Second heart sound or the dub is the closure of the aorta and pulmonary valve
Heart Sounds

12. Blood Flow into the Heart
Flows into the heart through the vena cava
Enters the right atrium then passes into right ventricle
Pumps blood to the lungs
Atrium and ventricle are separated by the AV valve which opens and closes to allow blood to flow through in one direction
Pulmonary arteries carry oxygen-poor blood and prevent blood flow back to the heart
Pulmonary veins allow blood to flow back to heart and into left atrium and then the left ventricle
Aorta large vessel that allows blood flow out of the heart and back into systemic circulation
An artery that prevents blood flow back to the heart
As blood flows through the heart, the body produces blood pressure
Blood Flow into the Heart

13. Electrocardiography
Monitoring heart sounds and rhythms of animals this done with electrocardiography
Evaluation of the electrical currents of the heart through the use of machines
One type of machine is the electrocardiogram (EKG or ECG)
Records the electrical currents of the heart
Rhythm of the heart is shown on a screen that is depicted in waves or lines that peak according to the heartbeats