| 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 |