Effect of Precision Feeding Strategy on Growth Performance and Nitrogen Excretion of Growing-Finishing Pigs

Abstract Text: The objective of this study was to assess the impact of moving from conventional to precision feeding systems on animal performance and nitrogen excretion in growing-finishing pig operations. Sixty randomly selected pigs (initial BW: 41.2 ± 3.9 kg) were used in a 84 d performance trial with pigs fed according to 1) a 3-phases feeding program (3P), providing within each phase a fixed proportion of premixes A (high-nutrient density) and B (low-nutrient density) calculated at the beginning of each phase to satisfy the LYS requirements of the 80^th percentile pig of this group; 2) a multi-phase group feeding program (MPG), in which pigs received the same blend of premixes A and B calculated at the beginning of each day to satisfy the LYS requirement of the 80^th percentile pig of this group; and 3) a precision feeding program (MPI), in which pigs were fed individually with daily tailored diets. Feed intake was recorded daily and BW weekly and these data used in a factorial method to estimate the daily nutrient requirements of each pig of the trial. Lean and fat body composition were assessed at the beginning of the trial and every 28 d by dual-energy X-ray absorptiometry (DXA). Neither ADFI (3.05, 3.07, and 3.05 kg/d), ADG (1.11, 1.11, and 1.10 kg/d), G:F (0.38, 0.37, and 0.37), average daily protein gain (161, 155, and 154 g/d), nor final BW (134, 135, and 136 kg) were affected (P > 0.05) in pigs fed according to the 3P, MPG, and MPI feeding programs, respectively. On average, 3P pigs ingested 23.8 g/d of standardized ileal digestible (SID) LYS and excreted 48.1 g/d of nitrogen. Compared to 3P pigs, MPG and MPI pigs reduced (P < 0.05) SID LYS intake by 17% and 27% and nitrogen excretion (P< 0.05) by 12% and 22%, respectively. Precision feeding is an effective approach for reducing LYS intake and nitrogen excretion in growing-finishing pig operations.

Keywords: nutrition, nutrient requirements, precision feeding.