Fish Health and Fish Diseases

In the course of 2008, Norwegian aquaculture produced 740 000 tonnes of salmon, 80 000 tonnes of rainbow trout, 14 000 tonnes (estimate) of cod and 5300 tonnes (estimate) of other marine species, representing a considerable increase from last year. For many years Norway has experienced a relatively favourable disease situation in farmed fish. The situation has, however, become slightly more complex in recent years.

In salmonid fish, pancreas disease (PD) gives grounds for concern. The industry has, however, united and implemented a series of concerted measures in an effort to eradicate this disease. Although it is too early to say whether the measures initiated by industry and the authorities have been effective, there are indications that the negative trend may have been stopped. This work is important not only in relation to eradication of pancreas disease, but also in relation to building a more robust infrastructure within the industry regarding fish health and control of future disease problems.

There is an increasing problem with salmon-louse resistance to various therapeutic treatments. Should this situation continue to develop it will have significant negative consequences for both wild and farmed fish. Salmon-louse control should be based on a broad range of methodologies and optimisation of existing treatments, as well as development of new control strategies. Both the industry and the authorities have increased efforts in these areas, but there is a need for even larger co-ordinated efforts over an extended period of time.

Transparency regarding the disease situation in individual farms is a basic necessity for maintenance of fish health on a national basis. Then and only then, may spread of disease be controlled. The National Veterinary Institute works towards compilation and quality assurance of disease related data.