French stakeholders in sea bass and sea bream aquaculture are uniting to develop a vaccine to kill the harmful Tenacibaculum bacteria, which destroys fragile alevins. The government-funded project, called Pathotrack-fish, may provide a two-pronged benefit: an end to alevin mortality from Tenacibaculum and a boost in revenues as the vaccine is rolled out across the globe.
Project coordinator Catherine Beutin of the French agency Aquimer talked to SeafoodSource about Pathotrack-fish, which involves two French hatcheries (Aquanord’s Ecloserie Marine de Gravelines and les Poissons du Soleil), three diagnostic and science firms (Phylogene, Labofarm and Biovac) and the French science agency INRA.
What is the project’s key objective?
The project, which has EUR 2 million in funding, will last for three years and by the end of this time we hope to have a “candidate” vaccine. One of the partners involved in the project estimates the cost of alevin mortality due to the Tenacibaculum bacteria at EUR 50,000, which includes the treatment and the loss of alevins. This bacteria is currently the biggest problem for the alevins, against which there is currently no vaccine, only a water treatment which is not 100 percent effective and not ecological because a chemical is added to the water.
This is also a confidential project with some of the partners injecting their own capital into the work. Should the vaccine be developed, partners will have exclusive use of the vaccine for a certain time, yet to be determined, before the vaccine is launched onto the wider international market.
The project is a collaborative effort with each partner bringing a complimentary competence to the effort; INRA, for example, is strong on bacterial knowledge and Labofarm makes “environments” for bacteria.
Tenacibaculum bacteria [which is in the Flavobacteriaceae family] affects all marine fish, not just sea bass and sea bream. But because the two hatcheries involved in the project breed these species, these species have become the focus of the research.
What are the key challenges moving forward?
One of the first challenges will be to find the most suitable environment to isolate the bacteria. Today, there isn’t a specific medium that enables us to isolate the Tenacibaculum bacteria.
In addition, there are the typical challenges associated with creating a vaccine, for example, anti-bodies [and] anti-genes.
The alevins are very fragile, only weighing a few grams, so a further path is to find the best possible method to administer the vaccine on the tiny bass and bream fish, either via a bath or through their diet, but not an injection.
Where is the market for French sea bass and sea bream alevin producers?
French hatcheries produce about 8 percent of the European production of sea bass and sea bream alevins, and the large majority is exported to international markets (more than 60 percent of the total according to Ifremer, the French agency). French hatcheries are particularly strong on production and the genetic selection; the partners involved in the project are renowned abroad.
How will ecological concerns be embraced?
One key element of the project is to enable the development of a sustainable answer to the bacterial problem. Currently, the fish farmers treat the water with a chemical solution in order to combat the harmful Tenacibaculum bacteria and help the alevins beat the bacteria. If we design a vaccine, farmers could stop using the chemical option.
