Livestock Vaccine Flashcards
T/F: vaccines prevent infection
False- they stimulate the immune response to get protection from disease
What are the goals of livestock vaccination
1) Improve animal health and welfare
2) Increase animal productivity
3) Reduce consumer risk
4) Disease eradication
T/F: 100% vaccine efficacy in 100% of animals is possible
False
-instead aims to increase the level of herd immunity
can achieve 70-80% response in the herd
the level of immunity in a population required to prevent an outbreak
herd immunity
How might herd immunity be achieved to make disease spread less likely
Vaccination
Prior illness
What is the immune response to vaccination goals in herd
Memory cells produce antibodies (B cells) and memory cells that will be actived to lyse target cells (T cells)
The initial antibody response that occurs ~4 days post vaccination produces
IgM
The second antibody response that occurs ~10-14 days post-vaccination produces
IgG
The cell mediated response occurs about ______ days post vaccination
10-14 days
The booster vaccination produces
secondary or anamnestic response
-Predominantly IgG
-Stronger Ab, longer duration
the primary vaccine response is
largely IgM and some IgG, shorter duration
response of Ab and T cell
What kind of vaccines are bacterin
killed, inactivated
formed exotoxins that are denatured (often with formulin)
must contain adjuvant
Toxoid vaccine
T/F: toxoid vaccines are immunogenic
True
-Stimulates antibody production
-Antibodies then bind to and nautralize the toxin
Toxoid vaccines must contain
adjuvant
How have we traditionally assessed vaccine efficacy
Serologic data
the level of immunity in a population required to prevent an outbreak
herd immunity
Killed vaccines require
adjuvant
result in more injection reactions and boosters
T/F: with killed/ inactivated vaccines, there is a risk of reversion to pathogenic wild type
False
Killed vaccines produce strong _________ but less robust _____
strong humoral
less robust cell mediated
Killed vaccines are safer in what patients
pregnant and young patients
What are the disadvantages of killed vaccines
-Require booster vaccination
-Slower onset of protection
-Hypersensitivities can be seen
-Narrower spectrum of protection
What are the advantages of killed vaccines
-Induce IgA, IgG production
-Stimulate memory T cell production
-Safe in pregnant and young patients
-Cannot revert to wild type
-Thermostable
Induce mild infection with live organisms from non-target hosts or attenuated to reduce virulence
Modified live vaccines