Marine yeast (Candida sake) cultured on herring brine side streams is a promising feed ingredient and omega-3 source for rainbow trout (Oncorhynchus mykiss)

A major challenge for the aquaculture industry is supply of sustainable feeds. promising model to achieve this utilize circular flows where feed ingredients, such as single cell protein, are cultivated using side streams food industry. The aim study was evaluate marine yeast Candida sake, produced on herring brine streams, a source protein and immune stimulant in salmonid fish. dry C. sake product contained 54% (3.3% lysine 0.8% methionine) 13% lipids (1.1% eicosapentaenoic, EPA, 1% docosahexaenoic acid, DHA). Four experimental diets were designed tested 9-week feeding trial juvenile rainbow trout (Oncorhynchus mykiss). control diet containing both fish plant-based ingredients constituted base which 20% (to effects digestibility, growth intestinal physiology), heat-treated downstream processing) 3% stimulatory properties, replacing soy concentrate) added. apparent digestibility coefficient fat gross energy above 80%, amino acids 90% regardless treatment, suggesting high bioavailability sake. All three performed equally regarding specific rate, conversion ratio functional health. These results suggest that alternative feeds presence EPA DHA represents an added value. heat treatment increased matter by 8% but decreased acid average 3%, indicating may not be optimal processing technique. Furthermore, inclusion lamina propria width TGF-β transcription, stimulating effect. Future research needed understand these modulatory supplementation.