GROWTH OF ATLANTIC SALMON Salmo salar FED SQUID AND SCALLOP PROCESSING BYPRODUCT HYDROLYSATES INCORPORATED INTO SOY PROTEIN CONCENTRATE (SPC)-DIETS

Gary Burr*, Bill Wolters, Fredric Barrows and Chong Lee
USDA-ARS-National Cold Water Marine Aquaculture Center, 25 Salmon Farm Road, Franklin Maine 04634
 

New protein ingredients are going to be needed to support the expansion of aquaculture.  Byproducts that are currently considered waste can be converted into feed ingredients for fish.  The purpose of this study was to determine the effects of squid and scallop byproducts on the growth of Atlantic salmon.  Five-hundred Atlantic salmon smolts were stocked twenty 0.2 m3 tanks (25 fish per tank).   After smolting, the fish were stocked in approximately 15 ppt well water.  Temperature was maintained at approximately 13-14°C for the duration of the study.  Fish were fed five experimental diets with automatic feeders Fish were fed one of: soy-protein concentrate (SPC) diet, SPC + 5% squid hydrolysate, SPC + 5% scallop hydrolysate, SPC + 2.5% squid hydrolysate + 2.5% scallop hydrolysate, SPC impregnated with squid hydrolysate.  Fish fed the diets with the hydrolysates had significantly higher final weights and average weight gain compared to salmon fed the SPC diet (see table below).  The fish fed the experimental diets containing the hydrolysates were offered more food resulting in an increased growth rate compared to the fish fed the SPC diet, although the increased growth rate was not significant.  The proximate composition of the fish did not significantly differ among treatments, with crude protein ranging from 64% to 69% by dry weight and crude lipid ranging from 17% to 19% by wet weight.  Overall, incorporating squid or scallop hydrolysates into the SPC-diets of Atlantic salmon smolts increased weight gain and did not affect the proximate composition of the fish.