highly significantP < 0.01
Furthermore, whereas we detected no significant differences between the 2 groups regarding MBW0.75 and FCR, the values obtained for FI, BWG, ADG, ADFI, and RFI were significantly higher in HR group ducks compared with those of ducks in the LR group ( P < 0.05), among which, the difference in RFI was found to be highly significant ( P < 0.01).