Laboratory Procedures PreVet Laboratory Techniques TM 1 Circulatory

Laboratory Procedures Pre-Vet Laboratory Techniques TM 1

Circulatory System Functions • Respiratory – O 2 and CO 2 exchange • Excretory – removes waste from body cells • Protection – clotting, transports white blood cells to infections • Nutrition – carries energy and food throughout the body • Regulatory – helps to maintain p. H and temperature • Hormonal – transfers hormones to organs Laboratory Techniques TM 2

Circulatory System Components • Heart- muscular, four-chamber 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 Laboratory Techniques TM 3

Circulatory System Components • 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 Laboratory Techniques TM 4

Circulatory System Components • 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 blood cells. Laboratory Techniques TM 5

Heart Circulation Aorta Pulmonary Arteriesto lungs Pulmonary Veins Cranial Vena Cava Left Atrium Right Atrium Left Ventricle Caudal Vena Cava Right Ventricle Laboratory Techniques TM 6

Major Veins Jugular veins Cephalic veins Right axillary vein Right brachial vein Cranial vena cava Caudal vena cava Ovarian vein Renal vein Testicular vein Right external iliac Femoral vein Saphenous vein Caudal vein Laboratory Techniques TM 7

Major Arteries Facial arteries Right axillary Right brachial Common carotid arteries Brachiocephalic Aorta Pulmonary artery Mesenteric arteries Ovarian artery Renal artery Testicular artery Right external iliac Femoral artery Caudal artery Laboratory Techniques TM 8

Structure of Blood is composed of : 40% cells and 60% plasma v The cells that in the blood are: v. Erythrocytes (red blood cells) v. Leukocytes (white blood cells) v. Platelets Laboratory Techniques TM 9

Erythrocyte (red blood cell) • The most abundant blood cell • Function – transport O 2 throughout the body Mammals – no cell nucleus Birds & Reptiles –cell nucleus Laboratory Techniques TM 10

Leukocytes (white blood cells) • Colorless (leuk=white) cells capable of movement that provide body defence • Two categories: – Granulocytes • Neutrophil • Basophil • Eosinophil – Agranulocytes • Lymphocytes • Monocyte Laboratory Techniques TM 11

Neutrophil • Function- to stop or slow down foreign organisms • They work by: – Phagocytosis – to eat bacteria and dead cells – Bacteriocidal – to kill bacteria Laboratory Techniques TM 12

Basophil • Functions – – Phagocytosis – Mediate allergic reactions – Produce heparin and histamine Laboratory Techniques TM 13

Eosinophil • Functions – – Moderate the inflammatory response – phagocytosis Laboratory Techniques TM 14

Lymphocyte & Monocyte • Lymphocyte – plays a vital role in immunity Ø T-cells (memory cells) – cells are sensitized to an antigen, remember that antigen and fight it off next time • Monocyte – largest blood cell Ø Function is phagocytosis Ø B-cells – divide to form many cells to fight an antigen Laboratory Techniques TM 15

Thrombocyte • Function – – Hemostasis (clotting) – stop bleeding by adhering to damaged vessels and clumping together, release proteins that help form a clot Laboratory Techniques TM 16

Urinary System Urethra Ureter Kidney Bladder Laboratory Techniques TM 17

The Kidney Cortex Medulla Renal artery Renal pelvis Ureter Renal capsule Laboratory Techniques TM 18

The Nephron Glomerulus Arterioles Bowman’s capsule Proximal convoluted tubule Distal convoluted tubule Loop of Henle Collecting duct Laboratory Techniques TM 19

Urinalysis Laboratory Techniques TM 20

Color • • Most speices are pale yellow to amber color Color correlates to specific gravity (sg) Lighter color= lower sg Darker color= higher sg Red color= hematuria (rbc in urine) Yellowish-brown foamy urine= presence of bile Rabbits have darker orange to reddish-brown Laboratory Techniques TM 21

Transparency • Clear, fresh urine is normal • Cloudy urine indicates the presence of cells, bacteria, crystals, or fats, but horse, rabbit, and hamster cloudy urine is normal • Flocculent describes urine with pieces of debris floating in it caused by cells, fats, and mucus Laboratory Techniques TM 22

Specific Gravity • Measures concentration or density of urine compared to distilled water. 3 ways to measure – Refractometer: refracts light through urine and measure density – Urinometer: bulb is floated in a cylinder filled with urine, read off a scale attached – Reagent strips: chemical pad that changes color when dipped in urine Laboratory Techniques TM 23

SG cont. • Increased sg could indicate dehydration, decreased water intake, acute renal disease, or shock • Decreased sg could indicate increased water intake, chronic renal disease. Laboratory Techniques TM 24

Chemistry • Evaluate: p. H, protein, glucose, blood, bile, etc. • Done with reagent strips • Determine diabetes, renal failure, liver infections, urinary tract infection, etc Laboratory Techniques TM 25

Sediment • RBC, WBC (large amounts mean disease or infection) • Bacteria (infection) • Crystals (irritating the urinary tract) • Casts: tubular clumps of cells Laboratory Techniques TM 26