By Alex Ploeg

The two most important topics in our industry in the years to come will be Animal Welfare and Biosecurity. Animal Welfare is playing an increasing role in discussions in governments worldwide about whether or not to allow the collection of animals from the wild for ornamental purposes or the circumstances under which captive-bred animals are raised and handled.

Biosecurity
Until now biosecurity has primarily played an important role in farming of food-producing animals. Biosecurity of non-food producing animals has always been important as well, but this was involved primarily in cases where risks are present for the introduction of disease which could affect the food- producing animals. In recent years, the risks for introductions of diseases which could affect local populations have also become increasingly important in the development of import legislation.

Use of medicines
The import legislation is not the only legislation where biosecurity is important. In the last few decades, we have seen that importers need more and more medication to treat the fish upon arrival. We have built up resistance in several of the disease-causing agents for often several medicines among an array of medicines commonly in use in our industry also including various antibiotics. For antibiotics in particular, the legislation is getting stricter and stricter, also because of the developing resistance of agents causing diseases in humans. The public pressure for stricter legislation for medicines is severe and to be honest, fully understandable.

The only way to avoid severe problems for our industry in the future is the implementation of much stricter biosecurity measures, in all stages of the supply chain, starting with the selection of brood stock by breeders and ending with the handling in the retail shops selling the fish to the consumers. Only with healthier fish with fewer diseases present in production systems, will it be possible to acclimate fish with much less frequent application of medication.
OFI is not the only organisation involved. Our colleagues of OATA in the United Kingdom have developed a good and practical manual on Biosecurity, which can be downloaded by OFI members from the Members' Area of our website.

DNA Multiscan
One of the aspects of improved biosecurity is improved methods of disease detection. OFI is involved as stakeholder in a research project in Belgium which aims to find an improved method of detection of several diseases in a single "scan", the so-called DNA Multiscan project (www.dnamultiscan.com).

The Belgian Scientia Terrae Research Institute (STRI), in cooperation with several European and North American research institutes, has already developed such a test for the horticulture industry (plants). Using a single test, it is possible to test for the most important plant diseases (mostly fungi and bacteria, as these are the most important hazards in this industry). The test not only detects the presence of the disease-causing agents with a very high accuracy, it also indicates how many of these are present in the sample. Most disease-causing agents can be present in low quantities without causing disease, however, if the level increases to a certain level, an outbreak can occur, even in healthy fish.

The researchers claim that it is only a small step to develop a similar multiple test for the most important fish diseases, as the principles are exactly the same. The test is based on the detection of certain parts of the DNA of the micro-organisms. Every organism, be it bacteria, fungi, viruses or others, have DNA as the carrier of the genetic information. Differences between organisms find their genetic basis in the DNA. If we can define the locations of DNA which are specific for one species, it is currently possible to show whether such bits of DNA are present in a sample. The testing is based on so-called PCR techniques, the same type of technique that is most commonly used for the detection of single diseases such as Koi Herpes Virus. The specific features of the DNA multiplan technique is not merely the fact that the presence of many different diseases can be tested using one test, but also that this can be done within a very limited time. The test will take no more than 36 hours.

For the horticulture industry, the test has been developed for almost 90 different fungi and bacteria. It should be possible to develop such a multi-test for the most important diseases in the ornamental aquatic industry as well. In fact, it is not necessary to develop new techniques, it is only necessary to find the specific bits of DNA which characterise specific disease-causing agents.

Application in our industry
For the ornamental aquatic industry, this development is an important one. Of course I realise that this is not the very cheap, easy, compact and still 100% accurate all-purpose test kit every keeper of aquarium fish would like to have. I also realise that although the 36-hour test period may be considered very fast for this type of testing, we can never wait this long before starting treatment if we see certain signs in ornamental fish, as the fish will be all dead before the test results are in. urthermore, the costs of one test might exceed the total value of the sick tank. Currently the price for a test on plant deseases costs about 70-150 Euro, depending on requested advise.

No, I do not see this DNA Multiscan as a practical test for diagnosing the disease of a certain fish in my tank with guppies. For marine tanks, expensive koi or discusfish, this might be different. But above all I see it as a very valuable tool in ensuring biosafe fish. As indicated above, importers are already facing more and more problems regarding fish health, as many of them carry all sorts of

viruses, bacteria and other microorganisms. They want healthier fish, but how can they ensure that the fish are healthy to start with?

This DNA Multiscan could be a tool for providing reassurance from breeders and collectors. If they regularly test with DNA Multiscan, this can prove that relevant diseases are absent in the breeding farm. The official test results can serve as a reassurance for biosafety for customers.

Furthermore, this test can play an important role in developing certified disease-free brood stocks.
For importers, the DNA Multiscan test can serve as a tool in finding a proper preventive medication for fish originating from one supplier. After testing, it becomes very clear which diseases have been imported with the fish and medication can be much more specific than before, which will result in less mortality but also less medication used.

OFI Participation
The development of the DNA Multiplan test method for ornamental fish is a research project. The project should be financed mainly by a grant from the Belgian Government under the TETRA program. The Government will, after official approval, provide 92.5% of the budget, the rest should be financed by participating industrial partners, in this case, the ornamental aquatic industry. The participating industrial partners will be considered preferred partners which are first in line to benefit from and/or profit from the results. Several Belgian importers have committed themselves to this project and OFI has also signed a declaration of intent to participate in this project and has reserved funds from the research budget. As a result, OFI members will be amongst the first to benefit from the research of this project.