Genetic variation in feed intake, growth and feed utilization in Atlantic salmon ( Salmo salar)

Abstract

Feed intake, growth and feed utilization were studied in 14 full-sib family groups of Atlantic salmon (seven sires, two dams per sire, 30 fish per family), with an average initial body weight of 148 g. Each full-sib family was held in replicate tanks with fresh water for two subsequent 5-week periods. Body weight increased by 12–52%, and the average daily feed intake (DFI), thermal growth coefficient (TGC) and feed efficiency ratio (FER) were 0.33% of BW (CV=21), 1.08×10 −3 (CV=35) and 1.14 g weight gain/g feed intake (CV=16), respectively. The effects of family and growth period on DFI, TGC and FER were significant ( P<0.05), with family explaining 31–32% of the variation. FER was positively correlated with TGC ( r=0.79, P<0.001, n=28). The salmon consumed an average of 450 g protein (CV=16) and 22.6 MJ gross energy (CV=18)/kg gain: 43% of the protein and 31% of the energy were deposited. When calculated per kilogram weight gain, the effects of family were significant for feed consumption and visceral deposition of protein and energy. The results indicate a genetic variation for feed intake, growth and feed utilization in Atlantic salmon.