RASTECH Magazine

News Feeding and Nutrition Sustainability
Canadian researchers find trout, salmon grow better with marine microbe oil

May 25, 2021  By  Nestor Arellano

Bailey Hart (left) and Angelisa Osmond (right), M.Sc. students, weighing rainbow trout as part of experimental activities in the lab.(Credit: Dr. Stefanie Colombo, assistant professor in Dalhousie’s Department of Animal Science and Aquaculture)

Fish grown in aquaculture systems do better when given a diet that contains marine microbe oil rather than oil obtained from wild-caught fish. This was what researchers from Nova Scotia’s Dalhousie University found out when they completely replaced fish oil used in the diet of farmed rainbow trout and Atlantic salmon with oil from a new strain of marine microbe.

Stefanie Colombo, an assistant professor in Dal’s Department of Animal Science and Aquaculture and a Canada Research Chair, tested oil from Schizochytrium (T18), a new strain of microbe.

Colombo and her fellow researchers found that  both trout and salmon grew as well or better than fish that were fed oil from wild fish.


The salmon and trout also stored more DHA in their fillets, which is important for consumers, according to a press release from the Dalhousie University.

“Inclusion of Schizochytrium sp. (T18) oil at high or low levels in the diet resulted in a similar growth performance as seen in trout fed the control diet; however, muscle and liver fatty acid profiles were impacted by diet,” according to the article the by the researcher which was published in the scientific journal MDPI. “Overall, our results showed that Schizochytrium (T18) is an effective source of omega-3 fatty acids in diets for rainbow trout.”

The findings are important for the aquaculture industry since it now provides operators and business owners a sustainable source of omega3 for fish feed. The aquaculture industry relies heavily on oil obtained from wild-caught fish, a practice that is not sustainable.

Print this page


Stories continue below