Effects of Precision Feeding on the Growth Performance and Variation of Growing-finishing Pigs

Abstract Commercial swine environments typically allow for a single dietary phase to be fed to pigs in a facility at a given time. As such, it is common practice to formulate diets to meet nutrient recommendations for the mean of the population, meaning required nutrients will be overfed or underfed to 50% of the population each. Sorting pigs and precision feeding by BW would allow heavy and light pigs to have more precise diets, thus maximizing growth performance. The objective of this study was to evaluate the effects of precision feeding compared to commercial practice. A total of 2,223 pigs (DNA 610 × DNA 241 or PIC 1050; 33.0 ± 5.32 kg BW) were housed in mixed-sex pens of 19 in a commercial grow to finish facility and used in a randomized complete block design for 71 days with three treatments: 1) Precision Feeding: heavy, medium, and light BW pigs sorted into 3 separate pens and fed unique diets with SID Lys:ME based on their respective BW category, 2) Size Sorting: heavy, medium, and light BW pigs sorted into 3 separate pens and fed a common diet with SID Lys:ME based on the population average, and 3) Commercial Practice: 3 mixed-BW pens of pigs fed a common diet with SID Lys:ME based on the population average. Experimental unit consisted of three pens representing each BW in each treatment, with a replicate having 9 pens. There were 13 replicates of each treatment. Individual pen weights and feed intakes were recorded at allotment and every 14 days thereafter. Pigs were individually weighed at day 0 and 71. Data were analyzed with the Mixed Procedure in SAS 9.4, with treatment as the fixed effect and replicate as the random effect. Overall, Size Sorting did not improve (P 0.05) performance compared to Commercial Practice. At d 71, Precision Fed pigs were 1.1 kg heavier (P = 0.011) compared to Commercial Practice. Precision Feeding increased (P = 0.026) overall ADG by 2.43% and improved (P 0.001) overall G:F by 3.12% compared to Commercial Practice. Precision Feeding reduced (P 0.001) d 71 BW standard deviation 3.3 kgs and reduced (P 0.001) BW coefficient of variation 3% compared to Commercial Practice. Size Sorting reduced (P 0.001) day 71 BW standard deviation 0.8 kgs and reduced (P 0.001) BW coefficient of variation 0.7% compared to Commercial Practice. Precision feeding pigs improved final BW and overall grow-finish ADG and G:F, while reducing coefficient of variation, compared to Commercial Practice.