The need for a sustainable aquaculture is increasing the use of plant ingredients in replacement to fishmeal and fish oil in diets for tambaqui Colossoma macropomum, which is leading to not detectable levels of docosahexaenoic acid (DHA) in its flesh. We evaluated the effect of a finishing plant diet supplemented with 5% of microalgae meal from Schizochytrium sp. (MD) on tambaqui growth, on proximal composition and fatty acid content of its flesh, comparing it to a non-supplemented diet. One hundred and sixty-two fish (489.67 g) were distributed into six tanks (2,000 L) and fed the experimental diets for a 90-day period. Three fish per tank were euthanized for analyses every 15 days. The MD did not affect the growth and proximal composition of fish flesh. The MD increased the DHA content (from 14.81 to 38.60 mg/g of lipids) and the n-3:n-6 ratio (from 0.16 to 0.51) in the flesh of fish, beginning on the 15th day and reaching the highest DHA content on the 71st day (39.81 mg/g of lipids). We recommend C. macropomum to be fed with a finishing diet supplemented with microalgae meal for 71 days before slaughter to improve the DHA content and n-3:n-6 ratio in the flesh.
Bibliographical noteFunding Information:
The authors thank FAPEAM (Fundação de Amparo à Pesquisa do Estado do Amazonas) for the scholarship to C.A.A. Cortegano and PAPAC Project (number 062.00718/2016) for the financial support in the review of the English text. To Dr. Janilson Felix da Silva and José Ribamar Benício Castro for the collaboration on sample collection. To Dr. Rogério Souza de Jesus for allow‐ ing the use of the Fish Processing Laboratory – INPA, Manaus, Amazonas, Brazil.
- n-3:n-6 ratio
- nutraceutical fish
- Schizochytrium sp.