Evaluation of Brewers Spent Grains with different levels of exogenous enzymes on the production performance and body composition of Nile tilapia (Oreochromis niloticus) and channel catfish (Ictalurus punctatus)

This study evaluated Brewers Spent Grains (BSG) and an enzyme additive (Allzyme (TM); ENZ) in practical diets for juvenile (similar to 5 g/fish) Nile tilapia (Trial 1) and channel catfish (Trial 2). Following a factorial arrangement, effects of three dietary levels of BSG (0, 270, and 550 g/kg) and three levels of ENZ (0, 0.2, and 0.4 g/kg) on production performance and whole-body composition of the fish were evaluated. Upon conclusion of the feeding trials, no effects of ENZ, or interactions between BSG and ENZ, were found. Fish survival was >85% and unaffected by diet. Reduced growth of tilapia (from 949% to 778%) and catfish (from 1802% to 1364%) as dietary BSG increased from 0 to 550 g/kg were observed. In these trials, weight gain was reduced in both channel catfish and tilapia at BSG inclusion rates of >= 270 g/kg and that the addition of exogenous enzymes did not improve BSG utilization.