Haemorrhagic smolt syndrome

摘要

FARM managers and associated staff have always been aware of the impact of infectious diseases on their business. Where this has occurred the losses may be minimal, but in some cases large numbers of fish have been lost. Research and investment have enabled farmers to choose to vaccinate against a range of diseases and for fish reared commercially this is now standard practice. However, so-called 'production losses' continue to add to mortality figures and profitability of individual companies. Suchdiseases do not always have an exact or known aetiology and fish affected by them are often simply referred to as 'poor doers', 'failing smolts' or 'losers', and are often more susceptible to other infectious diseases. In addition there is also increasing evidence that intensively rearing fish significantly alters some aspects of cardiac anatomy and physiology.