Vaccines Stimulate immune response “safe” (non-pathogenic) 1st fish vaccine (Duff 1942) –killed bacteria preparation of A. salmonicida –1st commercial vaccine- ERM (1976) – licensed vaccines (USDA) for 5 diseases in US

Vaccines Vaccines are a “proactive” approach Antibiotics are a “reactive” approach

Advantages of Vaccines Decrease disease impact Fixed cost for disease prevention Vaccinated fish often grow better than unvaccinated fish

Disadvantages of Vaccines Vaccine doesn’t eliminate disease organism Vaccinated fish could become carriers of disease –

What Characterizes an Acceptable Vaccine? Provide adequate protection under intensive rearing conditions Provide long-term protection Safe to animal and easily administered Cost effective (production, licensing, use)

Delivery Methods Injection - –Atlantic Salmon industry Immersion - protection, mass numbers of fish –Bacterin (killed bacteria preparation) Oral - most desirable, poor protection (poor uptake and breakdown in gut) Spray -

Vaccine Preparation Most are simple bacterins (early vaccines) Grow up bacteria Add formalin to kill Dilute and use as immersion Autogenous - vaccines made from specific isolates (on-site) –easier approval for use

Adjuvants/Immunostimulants Boost immune responses Increases length of exposure/protection Broadens effect of vaccine

Types of Adjuvants Glucans in feed - LPS - bacterial cell wall fraction (endotoxin) Oil bases adjuvants –Freunds complete adjuvant (FCA) –FIA- Aluminum salts

Management Proper management must accompany any vaccination program Effects on vaccine performance: – –proper administration