Sl. No. Vaccine Immunostimulants
1. Prophylactic for long duration with only one or two treatments. Prophylactic for short duration, require more treatments.
2. Efficacy of vaccine is excellent Efficacy of immunostimulants is good
3. Limited spectrum of activity. Wide spectrum of activity
4. No toxic side effects No toxic side effects
5. No accumulation of toxic residues No accumulation of toxic residues
6. No environmental impact No environmental impact
7. Enhance specific and nonspecific immune response Mainly enhance nonspecific immune system of larvae before specific immune system matures.
8. Difficult to vaccinate larvae of fish and shrimp Easy to vaccinate larvae of fish and shrimp
9. Costly Cost effective
Table 2: A comparison of characteristics of vaccines and immunostimulants.