Salmon becomes food for cod
New farmed species create new challenges for feed manufacturers. But the solution can lie in marine raw materials until now unused.
Scientists at Fiskeriforskning's department in Bergen, Norway, have discovered that the key to a better feed for farmed cod can be a marine raw material easily available at home: bones from farmed salmon.
Better appetite and faster growth
Wild cod eat a lot of crustaceans and thus have a mineral-rich diet. The scientists have now revealed that this can be carried over to the aquaculture industry.
The farmed cod had a noticeably better appetite when the scientists added the mineral-rich salmon bones in the feed, and the fish also grew faster. This in turn means that the farmed cod can be ready sooner for the fish counter.
"The fish that received 20 % salmon bone meal in the feed grew 10 % faster than the fish that received regular feed", says Scientist Jogeir Toppe as Fiskeriforskning.
It was not until the scientists mixed in more than 20 % salmon bone meal in the feed that the feed factor increased, i.e. that the fish ate more without growing correspondingly. But the scientists believe that by using untreated salmon bones with the fish meat, it is possible to increase the content of salmon bones in the feed up to as much as 40 % without increasing the feed factor.
Can save millions
By mixing in meal of salmon bones, the price of the feed also drops because you don't have to use as much of the expensive fishmeal that is used today.
"Also, use of untreated salmon bones with fish meat can replace the fish oil and some of the proteins that are used in the feed", he continues.
Toppe has calculated that it is possible to reduce the price of the feed by around 12 % by using meal of untreated salmon bones. Consequently, there can lie lots of money for the aquaculture industry in these research results. In 2005, production of farmed cod totalled around 11,000 tonnes, of which about 7,400 tonnes slaughtered weight were for sale in the market.
This means a consumption of approximately 13,000 tonnes of feed last year, and the industry could thus have saved several million by having such a feed of salmon bone meal available. Because cod farming is a national priority programme through the Norwegian Cod Breeding Programme, we can also expect this figure to be much higher in the coming years.
"The volume of salmon bones from the Norwegian aquaculture industry is large enough to ensure stable supplies of salmon bone meal for the feed industry, particularly if more of the salmon is processed domestically and we take care of the bones", says Toppe in closing.
The study is part of the efforts at Fiskeriforskning's department in Bergen to find new marine raw materials for use in feed for the aquaculture industry. The studies are financed by Fiskeriforskning and Stiftelsen RUBIN (Foundation for Recirculation and Exploitation of Organic By-products in Norway).
Contact scientist at Fiskeriforskning: Jogeir Toppe
