Genomic Resources for Immunology and Disease of Salmonid and Non-Salmonid Fish

Abstract

The development of aquaculture has increased interest in infectious diseases of fish due to the economic losses in fish farms. Although there are successful vaccines against bacteria, therapeutic treatments for viral diseases have yet to be established. The innate immune system is the first line of defense and therefore an important protection against pathogens in fish. The reason is the relatively inefficiency of the adaptative response in comparison with the unspecific response, given the evolutionary status and poikilothermic nature of these animals. In spite of this, not many innate immune genes have been cloned in fish. However, this number has increased lately owing to the recent advances in genomics and proteomics techniques together with functional studies of gene expression in vivo and in vitro. Many genes and regulatory pathways of biological processes, including defense mechanisms, could be identified and characterized. This knowledge will allow determining the molecular basis of these responses and also be used in the improvement of cultured species via effective fight strategies against pathogens, new vaccine design, and genetic selection of disease-resistant species. In this chapter, we review the application of these techniques to study immune response and disease resistance of non-salmonid and salmonid fish.