Skretting senior Researcher Grethe Rosenlund considers the feeds available prevent salmon from suffering heart issues. (Photo: Skretting/FIS)
Skretting researcher refutes findings by NIFES on vegetarian feed
Wednesday, November 02, 2011, 22:50 (GMT + 9)
Skretting is refuting findings published recently by the National Institute of Nutrition and Seafood Research (NIFES) by stating that “the commercial feeds sold today with a high content of vegetable raw ingredients do not produce salmon with heart problems,” said Grethe Rosenlund, senior Researcher at Skretting.
The article recently published by NIFES concludes that “Farmed salmon fed a diet that does not contain enough marine raw ingredients have a greater risk of suffering a heart attack.”
NIFES arrived at these findings via a sub-project of the extensive European Union- (EU) funded Aquamax project, in which salmon were fed a diet where 70 per cent of the fish oil was replaced with vegetable oil and 80 per cent of the fishmeal was replaced with vegetable proteins over a period of 12 months.
Said article determines that ”the feeding trial showed that salmon do not benefit from being vegetarians” because the fish “store body fat in the wrong places.” The results suggest that such a diet seem to be lacking essential nutrients for large-growing salmon.
Commercial fish feeds in the market today usually contain 16-17 per cent fish oil and around 20 per cent fishmeal, which is slightly lower than what it was just a few years ago. The percentage of non-marine raw ingredients is above 50 per cent.
”The trial NIFES refers to is several years old and shows what can happen if the composition of nutrients is not correct. We were involved in these trials, and have learnt from the findings that both this and other research has shown”, Rosenlund said.
She suggested that the article by NIFES is misleading.
“It is not primarily the ingredients that are important, but the nutrients. By compensating for vegetable raw ingredients generally not having an optimum composition of nutrients, through what we call MicroBalance we have developed a feed that does not give the problems NIFES refers to in its trials”, she said.
Still, she underscored the importance of NIFES’s research, as studies must constantly be done to test what works and what does not.
New findings, Rosenlund said, can slash dependence on marine raw ingredients in salmon feed, which is needed to ensure continued sustainable growth in the salmon industry.
The NIFES trial is one of many that add to this body of knowledge and which is included in further evaluations before changes are made to the commercial feed.
“In trials we have shown that we can reduce the content of the vegetable raw materials more than we have done today, without causing problems. You just have to make sure that the salmon are getting the right nutrients, and then it doesn’t matter if these are vegetable or not”, Rosenlund added.
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By Natalia Real
Photo Courtesy of FIS Member Skretting AS - Headquarters