Unit 17: Vaccination & Immunization

 Vaccination Mechanical act of administering a vaccine for the purpose of developing immunity in an animal Amount of immunity developed depends:  Animal’s state of health  Condition of the vaccine  Manner in which it is infected  Immunity is relative Can be overcome by massive exposure to germs

Unit 17: Vaccination & Immunization Vaccination not the final answer in disease control  Combine with: Proper nutrition Stress reduction Sanitary measures  Antigen-Antibody reaction After vaccine is injected  Stimulates formation of immune bodies against the disease  May be accompanied by signs of poor health

Unit 17: Vaccination & Immunization  Can produce the actual disease  Immune response depends on type of vaccination given: MLV Killed Antibody buildup is normal reaction to infection Helps keep disease-causing organisms from their normal infectious course Boosters may be used to supplement or maintain antibody levels

Unit 17: Vaccination & Immunization  Types of immunity Natural  Protection an animal has when it is born  Not associated with antibodies in the body fluids  Species resistance Can be specific to a certain species Ex. Scrapie and sheep  Breed resistance Variations in immunity between breeds Ex. Milk fever more prevalent in Holsteins than Jerseys

Unit 17: Vaccination & Immunization  Individual resistance Some individuals have higher immunity and will be able to overcome disease outbreaks Acquired immunity  Associated w/ presence of antibodies from another immune animal or form exposure to the disease  Active immunity Direct contact w/ disease causing organisms Body develops specific antibodies to counteract invasion  After disease  After vaccination

Unit 17: Vaccination & Immunization Relatively long-lived and often lifelong  Passive immunity Transferring antibodies from an immunized animal to a susceptible animal Ex. Colostrum immunity  Animals have ability to absorb antibodies from colostrum in first 24 hrs from birth  Tests are available to test amount of immunoglobulins in colostrum

Unit 17: Vaccination & Immunization  Biologic Agents Organisms have been prepared so that they can be safely given to livestock Livestock carry protection with them Modified Live Viruses  Grown in lab of other animal  Stimulate antibody function in the animal  Can give lower doses, but get high immune response  Not as safe for pregnant cattle

Unit 17: Vaccination & Immunization Killed viruses  Pathogen is killed  Produced in a suspension  Given in high doses relative to MLV  Safer for pregnant cattle

Unit 17: Vaccination & Immunization  Types of Immunizing Agents Viral Vaccines  Must be propagated in living cells  Can be grown either from tissue culture, or in host or non-host animals Bacterial Vaccines  High doses required to illicit an immune response  Bacteria grown on artificial medium  Usually given in killed form

Unit 17: Vaccination & Immunization  Often times altered so as to increase duration of protection  Vaccinating animals What you need:  Good syringe  Sharp, sterile needles  Sterile techniques  Animal restraint

Unit 17: Vaccination & Immunization Don’t use chemical disinfectants when using MLV vaccines  Inactivates the vaccine Follow administration instructions  Subdermal  Subcutaneously  Intramuscular  Usually all is given in one place Unless large doses are given, then multiple sites

Unit 17: Vaccination & Immunization Avoid vaccinating sick animals  Often will cause a disease outbreak  Animal has little ability to maximize the immunity given because of other pathogen, stress load  Proper Care of Biologics Improper care/handling can greatly reduce strength & effectiveness of the vaccine Must be free from contaminants  Don’t reuse needles

Unit 17: Vaccination & Immunization Discard containers only partially used, if not going to be used for awhile Keep refrigerated Empty MLV containers should be burned Understand expiration dates  Some may be used past the expiration date, but will not be at full strength  Some may not be used MLV bottles should be used w/in 2 hrs, or vaccine loses potency

Unit 17: Vaccination & Immunization Most are sensitive to light and heat  Store in cool, dark places to prevent deterioration Improper storage can result in failure of vaccine to work properly