Linking fish diseases and animal welfare in aquaculture – A study of the turbot herpesvirus

Abstract

Infectious diseases of fish are of major concern of the aquaculture industry, impacting upon economic growth, sustainability and financial viability. In Germany there has been a paucity of research in this area, and while German marine aquaculture is still in its infancy, the problems which this sector faces nationally in dealing with e.g. disease outbreaks, are similar to those encountered worldwide. The Geomar Helmholtz Institute for Ocean Research in Kiel, Germany, is ideally located to conduct studies of marine fish within the environment of the North and Baltic Sea. Our newly founded Aquaculture and Fish Disease group comprises experts in immunology, physiology, ecology and diseases of fish, as well as larval biology and evolutionary ecology. Our research focuses on species that are important for German and European marine Aquaculture, including sea bass Dicentrarchus labrax and turbot Scophthalmus maximus. The overall aim of our research is to maximize the productivity and sustainability of aquaculture through research-led improvements in disease characterization, prevention and diagnostics and animal welfare. By understanding the factors that contribute to disease outbreaks, such as variations in water temperature and quality, and the genetic background and stresses faced by farmed fish, we hope to devise new methods of predicting when infections will occur, and minimize their impact. Of particular interest is the way in which stress can affect the immune response of fish in aquaculture at each stage of their life history. Characterization of changes which occur in immune parameters following infection would facilitate identification of infections in aquaculture at an early stage, such that appropriate treatment can be begun before mortalities occur. We also plan to evaluate the potential efficacy of novel tools including siDNA and immunostimulation in disease treatment and prevention. In this context we are especially interested in the herpesvirus of turbot (Herpesvirus scophthalmi) and aim to characterize its influence on both its host and aquaculture as a whole. We will report some of our recent advances in this field.