The Circulatory System

1. The Circulatory System 8646-A Mr. Akin’s Animal Science Class

2. Circulatory consists of . . . Heart Veins Capillaries Arteries Lymph Vessels Lymph Glands

3. Specific Functions of the CS • Distribution of nutrients • Transportation and exchange of oxygen and carbon dioxide • Removal of waster materials • Distribution of endocrine secretions • Prevention of excessive bleeding • Prevention of infection • Regulation of body temperature

4. The heart

5. The Heart

6. Anatomy and Physiology of the Heart • Located in the thoracic cavity • Funnel-shaped, hollow, muscular organ • Housed in the pericardial sac = pericardium

7. Heart • The wall of the heart consists of 3 layers: • 1. Epicardium • Outer layer is actually the inside layer of the pericardium • 2. Endocardium • Consist of endothelial cells • 3. Myocardium • Middle layer of the walls

8. Left Ventricle Atrium Atrioventricular valve (AV) = bicuspid Aortic Valve Right Ventricle Atrium Atrioventricular valve (AV) = tricuspid Pulmonary Valve Heart = divided into left and right side Valves consists of two or three flaps of skin called leaflets.

9. Valves

12. Valves

13. Blood returns through the cranial and caudal vena cava Right atrium to ventricle to lungs through the pulmonary artery Returns in Pulmonary vein To left atrium to left ventricle Oxygenated blood goes out the body in the aorta Blood flow

14. Notice the black areas of the heart. This is an indication of diseased or dead tissue. Common heart lesions

15. Notice the "cauliflower" lesion on the walls of the hearts in the above photos. This is a thrombus (blood clot adhered to a blood vessel or the heart) and is usually found on the valves of the heart.

16. The hearts in these photos each have a hole that is in the septum, middle wall of the heart, connecting the two sides of the heart.

17. The heart sac has been opened and you can see that the heart is surrounded by fibrous material. This material is due to infection within the heart sac. This can be referred to as a "shaggy heart".

18. Blood Flow

19. Blood Flow

20. Flow through Body

21. The Heart Beat • Controlled by the action of the sinoatrial (SA) node • SA node – • Group of cells located in the right atrium that send out electric signals to make the heart pump • Heart’s “natural” pacemaker • Travel across to the AV node • Reacts to adrenaline • The Sinoatrial Node

22. Blood Vessels • Arteries – carry oxygenated blood to the body • Veins – carry unoxygenated blood to the lungs • Capillaries – where O2 and CO2 change; connect arteries to veins.

23. Capillary Bed

24. Other than the Lungs . . . Blood passes through: • Kidneys - filter much of the waste from blood • Small Intestine - picks up nutrients • Liver - filters sugars from the blood and stores them

25. A & P of Blood • Expressed as % of body weight - 7.7% in cattle - 8.0% in sheep - 9.7% in horses

26. Plasma • Comprises 50 to 60 percent of the total volume of blood • Plasma is a straw-colored liquid = 90% H2O and 10% solids • Solids = inorganic salts and organic substances like antibodies, hormones, vitamins, enzymes, proteins, and glucose.

27. Erythrocytes = bioconcave • RBC’s – Contain Hemoglobin – Hb is made of Fe • Leukocytes • WBC’s – two types • Platelets • Blood clotting

28. Erythrocytes

29. Erythrocytes • Live 90 to 120 days • Reabsorbed by the spleen, liver, bone marrow, or lymph nodes. • Anemia = results when a subnormal level of RBC’s and Hb exists. Other causes can be caused by parasites • Hemoconcentration = normally caused by by dehydration from vomiting or diarrhea

30. Leukocytes • Two categories: • Granulocytes • Neutrophils – made in bone marrow; fight disease – pus- abscess • Eosinophils – contain mostly histamine – indicates allergies • Basophils – rare in blood; responsible for the symptoms of allergies • Agranulocytes – produced by the lymph glands, spleen, thymus • Monocyte – absorb disease, do not produce pus but join body tissue • lymphocyte • WBC’s differ from RBC’s because they have a nucleus and free movement

31. Pus and Abscess

32. Abscess

33. Vertebral Abscess from tail docking

34. Abscess

35. WBC attacking bacteria

36. WBC and RBC comparison

37. Platelets • Coagulation – blood clotting and healing • Normal blood clotting times: • Cattle = 6.5 minutes • Swine = 3.5 minutes • Sheep = 2.5 minutes • Horses = 11.5 minutes

38. Fibrinogen • Is a fiberous protein in the blood that reacts with thrombin produced from the injured tissue to make a threa-like mass called Fibrin. • Vitamin K is IMPORTANT in this feat!

39. Blood Types in Animals • Some may cause disease in offspring • Example: • Has been used in identifying swine that has PSS (Porcine Stress Syndrome)

40. Lymph System • An accessory to the Circulatory system • Responsible for for filtering foreign substances from the lymph.

41. Lymph System

42. Lymph Node and Glands • Scattered among the vessels • Produce Lymphocytes and Antibodies • Each lymph gland has its own blood supply and venous drainage.

43. Lymph Node

44. Lymph NodeBovine TB in Wild Hog

45. Temperature • If temp is elevated above norm, then the animal has a fever. • Many things other than ill health affect temp. • Excitement • Exercise • Digestion • Rest • High Surrounding Temp

46. Temperature RangeNORMAL

47. Temperature is usually taken in the rectum in animals.

48. The End • All Information came from 8646-A IMS material and pictures from random websites with web addresses tied to the pictures.