In Lelystad we have a specialized fish and shellfish diseases laboratory. This is the one complete diseases laboratory in the Netherlands for cultured fish for human consumption, ornamental and wild fish and shellfish.
In 1985 we started our fish diseases research. In 2000 the shellfish diseases research was added. We have broad experience and expertise on various fish and shellfish diseases. It is consulted frequently for its diagnostic service, its expertise on diseases, and as partner for collaboration in research and network projects by both national and international parties.
The fish diseases laboratory was set up in 1985, and the task on shellfish diseases was added in 2000. The laboratory has the following core tasks:
- Serving as a knowledge and advisory centre for the Dutch Ministry of Agriculture, Nature and Food Quality (LNV);
Diagnosing diseases for the aquatic industry, and the ornamental and wild fish branches:
- In case of fish disease at fish farms
- At suspicion of notifiable fish and shellfish diseases, in cooperation with the Food and Consumer Product Safety Authority (Voedsel en Waren Autoriteit)
- For certification of live fish for export, in cooperation with the Food and Consumer Product Safety Authority (NVWA).
- Provide expertise by consultancy for the government and the aquaculture branch regarding fish and shellfish diseases
- Research on fish and shellfish diseases that occur in the Netherlands.
The laboratory is the Dutch National Reference Lab (NRL) for fish and shellfish diseases for the EU. It was the first fish diseases laboratory in Europe accredited for quality standards ISO 9001 and 17025 (EN 45001). The laboratory has an impressive national and international network, in which knowledge and materials are exchanged.
The inoculated agar plates are incubated at room temperature, as fish are cold-blooded animals and their pathogenic organisms have adapted to that temperature. In case a pure culture of bacteria results, an antibiogram is made, so that the fish owner can choose an appropriate antibiotic to treat the disease. In parallel to this process, the bacteria are characterized by classic and/or molecular techniques.
For virus isolation, a suspension of the fish organs is put on fish cell cultures to cultivate any virus that may be present. The morphology of the virus can be examined with an electron microscope. The virus is generally characterized with specific antibodies that neutralize the particular virus. Moreover, for various viruses PCR-tests (sensitive rapid diagnostics) are available. After the name of the virus is known, specific recommendations are made, for example regarding changes in the water temperature in the fish culture system, to inhibit clinical disease.
For histopathology, the fixed tissue is sliced and stained in such a way that it can be examined with a microscope. This makes it possible to see alterations at cell level that indicate a viral, bacteriological or other disease. This method also enables detection of very small parasites in the tissue or in cells.