Norwegian firm discovers novel way to preserve live feed for fish larvae

Norwegian fish feed maker Planktonic AS has developed a novel and game-changing techniques to use marine crustacean nauplii, CryoProduct, both commercially and sustainably. It discovered a way to cryopreserve the nauplii in large user-friendly entities, and to revive them as live individuals after thawing, reports CORDIS, the European Commission's Community Research and Development Information Service.

 

Crustacean nauplii, the offspring of many types of crustacean zooplankton, is the natural first feed for most fish larvae.

 

"Our overall vision was to upscale, pilot and commercialise the innovative CryoPlankton production process for cryopreserved marine crustacean nauplii. This can replace conventional live feeds used at marine hatcheries," explained lead researcher Dr. Nils Egil Tokle, chief technology officer of Planktonic AS.

 

A large-scale, industrial trial showed that the vulnerable period during which larvae consume live feed could be greatly reduced compared with the time needed when the fish juveniles exist on diets commonly used at marine hatcheries.

 

The project managed to scale up production more than they had estimated initially, producing more than 8 tonnes. Protocols developed at end-users' hatcheries resulted in fish juveniles that showed 50-100% higher growth rates and far higher rate of survival compared with the control treatments.

 

The produced fish juveniles were also of better quality, with low deformities and high stress-resistance.

 

The project likewise found a way of making the process more environmentally friendly by reducing the amount of plastics normally associated with the process.

 

The new system is also more efficient as it uses just one unit to thaw, wash and revitalise the nauplii, which means it is more practical to undertake at the end-user's location. The whole process takes just half an hour a day. "Conventional live feed diets require a lot of time and considerable skill", explained Tokle.

 

The team believes CryoPlankton can help the aquaculture industry overcome problems such as growth, survival, vitality and stress-response. "One of the reasons for high mortality is the presence of pathogenic bacteria in conventional live feed diets. No pathogens have ever been detected in CryoPlankton, and fish producers have even medicated infected fish larvae with our product," Tokle said.

 

PHOTO FROM CryoPlankton2