Fish disease preventing strategies

Abstract Infectious diseases cause severe problems in the aquaculture industry, with viral diseases being responsible for the greatest losses in production. Disease prevention strategies still have some limitations in terms of safety and efficacy. Antimicrobial peptides (AMPs) are molecules of the innate immune system, one of the first lines of defense against pathogens. Usually they not only exhibit antimicrobial activity, but also modulate the immune response. This review focuses on fish AMPs and their antiviral and immunoregulatory activities in order to assess their potential relevance to aquaculture. Since fish depend on their innate immune defenses more than mammals, they could be an alternative source of novel antiviral compounds. 

Prevention is in the first line of disease management, and the development and implementation of biosecurity strategies for fish diseases is exercised at national level and is embodied in the codes of practice of several international organisations such as the EU 2006 Directive and the OIE code of practice. Oidtmann et al. (2011) provide an overview of international and national biosecurity strategies in aquatic animal health. Preventative measures on the whole require more risk analysis and closer adherence than they currently enjoy so that they may become a higher priority. Unfortunately, the preventative measures most closely adhered to tend to be largely those most closely regulated. Some of these preventative measures as out-fined below are subjected to intensive research and are dealt with elsewhere in this book. 

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