Nutrient digestibility of selected microalgae as sustainable ingredients in aquafeed

Whole-cell dried microalgae biomass represents possible candidate ingredients for more sustainable aquafeed. The study estimated the nutritive value of Tetraselmis suecica, Tisochrysis lutea, Chlorella sorokiniana, Nannochloropsis ocellata and Arthrospira platensis dried biomass for rainbow trout, a carnivorous fish species. Significant differences were recorded in the apparent digestibility coefficients of nutrients among the microalgae biomasses. The highest values were recorded for T. lutea (90.6% for d.m.; 92.6% for crude protein; 90.0% for organic matter and 94.3% for energy) while the lowest were registered with C. sorokiniana (52.6% for d.m.; 63.1% for crude protein; 57.9% for organic matter and 61.8% for energy).