1. Animal Diseases

2. Disease Broad definition – not being at ease or uncomfortable
Producers have a vested interest to keep their animals healthy

3. Healthy Animals Grow faster and produce more profit for their owners
Some diseases are mild, others may be severe and cause rapid death

4. Sick animals Usually display outward signs of illness
Animal may be droopy, go off feed and water, be restless, have a dull haircoat

5. Infectious diseases
Caused by microorganisms that invade the animal’s body
Usually contagious diseases that the animal can pass to another animal

6. Bacteria Live in a wide range of conditions
Live on and in the bodies of all animals
More numerous than the cells of the body

7. Bacteria Many are beneficial
Those living in the stomachs of ruminant animals aid in digestion

8. Bacteria Useful in production of foods such as cheese and sauerkraut
Many can be harmful
Invade the cells of an animal’s body

9. Parasitic bacteria
May harm the animal by feeding off the body cells or secreting a material known as a toxin

10. Toxin
Substance that causes harm to an organism
A poison

11. Harmful bacteria When large numbers invade, the animal becomes ill
Type and form of the illness depends on the type of bacteria that invades the animal

12. Cocci Round spherical shaped bacteria
Some forms of pneumonia and strep are caused by this bacteria

13. Bacillus Rod shaped Single, pairs, or arranged in chains
Cause some serious diseases in animals

14. Bacillus Anthrax Tetanus Blackleg Intestinal coliform
Salmonella and tuberculosis

15. Spirilla Shaped like spirals or corkscrews Very motile
Require moist atmosphere to live

16. Spirilla Live very well in the reproductive tracts of animals
Leptospirosis
Vibrosis and spirochetosis

17. Most bacteria Can be controlled by the use of antibiotics
Penicillin was one of the first
Produced from extracts of molds

18. Penicillin Many forms are now produced
Very effective against bacterial infection.

19. Viruses
Very tiny particle of matter composed of a core of nucleic acid and a covering of protein that protects the virus

20. Viruses Have characteristics of both living and nonliving material
Are on the borderline between living and non living

21. Viruses
Made up of some of the material found in cells but are not cells because they do not have a nucleus or other cell parts.

22. Viruses Do not grow and cannot reproduce outside a living cell
Once inside a living cell, virus reproduces using energy and materials in the invaded cell

23. Viruses Harm cells by causing them to burst during reproduction
And by using material that the cell needs to function properly

24. Virus
Viral diseases cause the animal to be sick by preventing certain cells in the body from functioning properly

25. Virus More difficult to treat than bacterial diseases
Antibiotics are not effective against viral infections

26. Viral diseases Foot and mouth disease Influenza Hog cholera
Pseudorabies

27. Viral diseases
Best means of dealing with them is prevention

28. Protozoa Microorganism that causes disease
Single celled organisms that are often parasitic

29. Protozoa Cause harm by feeding on cells or producing toxins
African sleeping sickness
Anaplasmosis

30. Protozoa Coccidiosis One of the most costly poultry diseases
Caused diarrhea and weight loss

31. Protozoa
Most can be controlled by drugs

32. The immune system Several lines of defense in fighting disease
Physical barriers that keep pathogens out

33. The immune system
Nostrils are lined with hairs that attract particles that harbor germs before they can enter the body

34. The immune system
Mucous membranes secrete viscous water substance that traps and destroys bacteria and viruses

35. The immune system
Digestive and respiratory systems – greatest avenue for entry
Some disease germs can live in the soil for many years

36. Soil borne disease
Animals come into contact with the ground when they graze
Many pathogens are breathed in by livestock

37. Germs Swallowed by animals are destroyed by digestive enzymes
Inhaled germs are trapped in mucous membranes of respiratory tract

38. 2nd line of defense Blood cells White and Red
Red – carry oxygen and other nutrients to other body cells

39. White Blood Cells Are produced in the bone marrow
Circulate throughout the body to get rid of worn out cells

40. Phagocytes White blood cells that intercept and destroy pathogens
Also migrate to certain organs and remain there to intercept pathogens

41. White Blood Cells
Circulate through other body fluids and the mucous membranes

42. Phagocytes
Release chemicals that can induce the production of more white blood cells to help fight disease

43. Phagocytes
An elevated WBC count indicated that there are disease organisms present in the animal’s body and a large number of phagocytes have been produced to combat them

44. Lymphocytes Lymph glands that produce certain WBC’s
These cells react to foreign substances by releasing chemicals that kill the pathogen or inactivate the foreign substance

45. Antigens Substances that cause the release of chemicals
May be viruses, bacteria, toxins, or other substances

46. Antibodies
The chemicals released by the lymphocytes

47. 2nd Immune Response
Lymphocytes become memory cell and are ready to release the antibody if the antigen enters the body at a later time

48. 2nd Immune Response Response occurs much more quickly
Lasts longer than primary response

49. Immunity
Means than an animal is protected from catching a certain disease
Animal’s body is capable of producing enough antibodies fast enough to neutralize the disease

50. Immunity Active or passive
Active –animal is more or less permanently immune
Passive – animal is only temporarily immune

51. Immunity Animals are born with some immunity
Colostrum is rich in antibodies
Serve the new animal until its own immune system can take over

52. Immunity
As the animal is exposed to more antigens, antibodies build up within the animal.
Naturally acquired active immunity results from the animal actually contracting the disease and recovering

53. Artificial Active Induced by injecting antigens into the animal
Causes phagocytes to react without making the animal seriously ill

54. Edward Jenner Late 1700’s Began vaccination process
Smallpox and cow pox
Collected material from sores of people with cowpox

55. Edward Jenner Injected healthy people with material
Became mildly ill with cow pox
Then were immune

56. Louis Pasteur
Developed several vaccines following Jenner’s lead

57. Vaccines Live Killed or weakened strain
Both stimulate production of antibodies
Killed – less dangerous when compared to live vaccine

58. Noninfectious Disease
Not contagious
Genetic diseases
Caused by defects in the genes
Problem or disease can be passed from parent to offspring

59. Genetic Diseases Cannot be spread through contact with other animals
Control of genetic diseases, using good selection practices
Avoid breeding animals that are known to have genetic defects in their line

60. Nutritional Diseases Milk fever in dairy cattle
Cows lie down and are unable to stand
Insufficient amount of Ca in the bloodstream

61. Milk fever Usually cured by injection of Ca salts
Effects are immediate and dramatic

62. Overeating Founder – horses, cattle and sheep Eat too much grain
Causes feet to become inflamed and hooves to grow upward and outward

63. Poisoning Moldy feed can contain toxins
Aflatoxins and ergot – fungi that grow on grains
Grazing on poisonous plants

64. Disease prevention Vaccination
Humans can carry disease from one farm to another
Many farms require plastic boots be worn over the shoes of visitors

65. Quarantine Isolation of newly purchased animals
Government regulates quarantine for animals coming into the US

66. Quarantine
Many states have quarantine periods or require health papers for animals crossing state lines
Animals tested positive for Brucellosis (Bangs) are branded and sent to slaughter.