1. Laboratory Techniques and Procedures Objective 4.01: Implement proper techniques for collection and analysis of laboratory samples

2. Circulatory System Functions Heart, blood, vessels, and lymphatics Functions: ◦ Respiratory – O 2 and CO 2 exchange ◦ Excretory – removes waste from body cells ◦ Protection – clotting and transporting white blood cells to infections ◦ Nutrition – carries energy and food throughout the body ◦ Regulatory – maintain pH and temperature ◦ Hormonal – transfers hormones to organs

3. Circulatory System Components Heart – muscular, four-chambered pump that drives the circulatory system Pericardium – fibrous sac that encloses the heart Artery – elastic vessel with thick walls to maintain high pressure while carrying blood away from the heart Vein – thin-walled vessel that carries deoxygenated blood to the heart

4. Capillary – microscopic vessel that forms a network between arteries, veins, and body tissues Lymph system – consists of lymphatic vessels & tissues (tonsils, thymus, spleen, lymph nodes) that play an important role in immunity and disease prevention

5. Lymph node – bean-shaped structures located throughout the body that produce lymphocytes and monocytes, and filters bacteria, foreign bodies, and malignant cells Spleen – largest lymph organ, produces lymphocytes and monocytes, stores red blood cells and iron, and destroys old red blood cells

6. Blood Circulation Through the Heart Problems in the right side of the heart will cause the abdomen to fill with fluid (ascites) Problems in the left side of the heart will cause lung congestion Flow of blood through heart in this order: right atrium  right ventricle  pulmonary arteries  lungs  pulmonary veins  left atrium  left atrium  left ventricle  aorta

7. Cardiac Cycle Video https://www.youtube.com/watch?v=5tUW OF6wEnk https://www.youtube.com/watch?v=5tUW OF6wEnk

8. Major Arteries & Veins Aorta – largest artery that sends blood from the heart to the body Brachiocephalic – branches from the aorta to send blood to the head and right side of the body Common carotid arteries – (left & right) run up both side of the neck and supply blood to the head

9. Coronary arteries – wraps around the exterior of the heart and supply blood to the heart muscle Facial artery – wraps under lower jaw and is used to take the pulse on a horse or cow Femoral artery – runs down the inside hind leg; used to take the pulse on a cat or dog Mesenteric – supplies blood to the intestines

10. Renal artery – supplies blood to the kidney Pulmonary arteries – carry deoxygenated blood to the lungs Pulmonary veins – carry oxygenated blood to the left atrium Cranial vena cava – returns blood to the heart from the head, neck, and forelegs Caudal vena cava – returns blood to the heart from the thorax, abdomen, and hind legs

11. Cephalic vein – runs along the front of the foreleg Jugular vein – runs down the neck and returns blood from the head Renal vein – returns blood from the kidney to the caudal vena cava Femoral vein – runs along the inside of the hind leg Saphenous vein – an extension of the femoral vein

12. Heart

13. Major Veins

14. Major Arteries

15. Structure of Blood Composed of cells and plasma (liquid portion of blood) ◦ 40% cells  Erythrocytes (red blood cells)  Leukocytes (white blood cells)  Platelets ◦ 60% plasma Typically blood volume comprises 6% - 8% of the animal’s total body weight

16. Blood Cells Hematopoiesis blood formation & development The formation and development of blood cells

17. Blood Cells All blood cells develop in the bone marrow from one type of cell called a hemocytoblast In young animals blood is produced in all bones In adult animals blood is produced in the pelvis, ribs, vertebrae, femur, and humerus

18. Erythrocytes (Red Blood Cells) Most abundant blood cell Function: to transport O 2 throughout the body Contains: hemoglobin (a pigment that contains iron and gives blood its red color when combined with O 2 )

19. In mammals the red blood cell is non-nucleated In reptiles and birds the red blood cell is nucleated Red cell’s life span in dogs and humans is 120 days, but it varies among different species

20. Leukocytes (White Blood Cells) Colorless, nucleated cells capable of moving throughout the body Function: body defense Divided into two categories: ◦ Granulocytes ◦ Agranulocytes

21. Granulocytes Produced in the bone marrow Have lobed nuclei and granules in their cytoplasm Neutrophils, basophils, and eosinophils

22. Neutrophil Has red and blue granules in cytoplasm Function: stop or slow down foreign organisms How they work – 1.Phagocytosis: to eat bacteria and dead cells 2.Bactericidal: kill bacteria How they get to infection site – 1.Sticky and can migrate through vessel walls 2.Release chemicals to attract other neutrophils to the infection site

23. Basophil Has dark purple granules in cytoplasm Function: phagocytosis, mediate allergic reactions, and produce heparin and histamine

24. Eosinophil Has orangish-red granules in the cytoplasm Function: moderate the inflammatory response and phagocytosis

25. Agranulocytes Produced in lymphatic organs Have rounded nuclei, and no granules in the cytoplasm Lymphocytes and monocytes

26. Lymphocytes Has a round nucleus and plays a vita role in immunity Two categories: 1.T-cells (memory cells) – long-lived; once they are sensitized to an antigen, they remember it so that next time they can fight off that antigen 2.B-cells – encounter an antigen and divide to form many cells that all produce the same antibodies to fight the antigen

27. Monocyte Has an irregular shaped nucleus Largest cell in the blood Function: phagocytosis

28. Thrombocytes (platelets) Main function: hemostasis (clotting) Platelets are 1/3 the size of a red blood cell Stop bleeding by adhering to damaged vessels and clumping together and releasing proteins that help form a clot Average life span: 10 days

29. Hematology Study of the structure of blood and the tissues that produce blood Lab tests most commonly performed in vet medicine: ◦ PCV or hematocrit ◦ White cell count ◦ TPP (total plasma protein) ◦ Blood film evaluation

30. PCV – Packed Cell Volume Measures percentage of red blood cells in the total blood volume Capillary tube is filled with fresh anticoagulated blood, sealed with clay, and centrifuged for five minutes Results read using special scale Animal with PCV below normal is said to have anemia

31. Normal PCV values: Dog: 37 – 55 Cat: 30 – 45 Horse: 32 – 48 Bovine: 24 – 46

32. TPP – Total Plasma Protein Measurement of proteins produced mainly by the liver Measured using a capillary tube of blood, broken at the plasma layer, plasma placed on a refractometer Elevated TPP is a sign of inflammation, infection, or dehydration Decreased TPP occurs normally in newborns and pregnant animals

33. Blood Film Evaluation Used to determine size, color, and shape of cells and abnormalities in their formation Used to look for blood parasites such as microfilaria of the heartworm

34. Prepared by spreading a drop of blood on a slide, drying the slide, staining with Wright’s stain Evaluated by scanning under high power for abnormalities Abnormalities appear in the RBC as color changes in the cell, abnormal cell shape and size, and foreign bodies within the cell

35. Blood Chemistry Procedures Vacutainer tubes have a vacuum created to place a needle and syringe into a rubber plunger Different tubes for specific requirements – different colors to identify

37. Red Top – sterile or no anticoagulant that contains a gel separator Tiger Stripe – contains no silicone, gel separators, anticoagulants, or additives of any kind Lavender Top – sterile, contains EDTA as the anticoagulant Green Top – sterile, contains lithium heparin as the anticoagulant Light Blue Top – sterile, contains sodium citrate as the anticoagulant Gray Top – sterile, contains potassium oxalate and sodium fluoride as the anticoagulant

38. Each test requires a specific amount of blood, serum, or plasma to run the sample Allow the samples that require centrifuging at least 30 minutes to clot prior to spinning but not more than 60 minutes

39. Specific Procedures Complete Blood Count – evaluates the different types of WBCs Blood Smear – evaluates blood cell morphology

40. Specific Procedures PCV – measurement of the percentage of RBCs in whole or unclotted blood (also a hematocrit) Plasma Protein (total protein) – measures the ratio of protein within the blood and checks the hydration of the patient

41. Videos Veterinary Blood Testing: https://www.youtube.com/watch?v=o00e U2sqRtU https://www.youtube.com/watch?v=o00e U2sqRtU Vet Tech Training-Basic Blood Collection: https://www.youtube.com/watch?v=uYyh3 DIQ91c https://www.youtube.com/watch?v=uYyh3 DIQ91c