“…The retention of these nutrients has been documented as an important promoter of fish growth, critically supporting various physiological functions in fish including energy metabolism, tissue growth, and reproduction (Li et al 2009, Radhakrishnan et al 2020. Notably, phosphorus is an essential mineral for skeletal development and energy metabolism (Sugiura et al 2004, Fontagné et al 2009, Schamber et al 2014, whereas dietary protein is essential for muscle development and maintenance (Vareltzis 2000, Nemova et al 2021, and lipids provide a concentrated energy source necessary for the development and maintenance of cell membranes (Watanabe 1982, Izquierdo et al 2000. Consistent with our nutrient retention results, rainbow trout, Atlantic cod (Gadus morhua L.), and Atlantic salmon fed diets with higher phosphorus, protein, and lipid levels, respectively, showed positive correlations between growth and nutrient retention (Lellis et al 2004, Hansen et al 2007, Hixson et al 2017.…”