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Impact of feeding diets containing corn distillers dried grains with solubles (DDGS) with variable predicted NE content on growth performance and carcass characteristics of growing-finishing pigs
The NE system is increasingly being adopted in the U.S. because of increased use of high-fiber feed ingredients such as DDGS. However, limited data are available on the NE content of corn DDGS for swine. Illuminate® provides NE estimates based on chemical composition for various DDGS sources, but these values require validation. The objective of this study was to determine growth and carcass responses of growing-finishing pigs fed 4 DDGS sources with increasing NE (as-fed) content estimated by Illuminate®. Pigs (n = 432) were blocked by initial BW (22.0 ± 4.3 kg) and pens were allotted randomly to 1 of 4 dietary treatments (9 pigs/pen, 12 replicates/treatment). Treatments consisted of corn-soybean meal diets containing 40% DDGS from: 1) low NE (2,083 kcal/kg; LOW), 2) medium-low NE (2,255 kcal/kg; ML), 3) medium-high NE (2,469 kcal/kg; MH), and 4) high NE (2,743 kcal/kg; HIGH), and were fed using a 4-phase feeding program. Diets met or exceeded NRC (2012) nutrient requirements and were calculated to contain the same standardized ileal digestible Lys:NE within phases. Growth performance and carcass data were analyzed using the MIXED procedure of SAS. Overall, ADFI of pigs fed LOW was less than ML, but greater than MH and HIGH. No differences were observed in ADG among treatments. Gain:feed was reduced in pigs fed LOW and ML compared with MH and HIGH. No treatment differences (P > 0.40) were observed in HCW, dressing percentage, backfat depth, LM area, and carcass percent fat-free lean. Assuming NE content of corn and soybean meal based on NRC (2012), NE estimates were calculated for each DDGS source using the NRC (2012) model to match the model-predicted G:F with the observed G:F. In conclusion, G:F responses of pigs did not correspond to the increasing NE estimates of the 4 DDGS sources and suggest that NE may have been overestimated for ML and HIGH DDGS sources, and underestimated for the LOW and MH DDGS sources. However, variable NE content of DDGS sources had no impact on carcass composition of growing-finishing pigs.
Item |
LOW |
ML |
MH |
HIGH |
SEM |
ADFI, kg |
2.57a |
2.70b |
2.47c |
2.45c |
0.033 |
ADG, kg |
0.89 |
0.92 |
0.91 |
0.90 |
0.014 |
G:F |
0.362a |
0.353a |
0.385b |
0.385b |
0.004 |
DDGS NE1, kcal/kg (as-fed) |
2,377 |
1,924 |
2,612 |
2,513 |
|
a,b,c Within a row, means without a common superscript differ (P < 0.05). 1 Calculated NE of DDGS using NRC (2012) model |
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Keywords:
Carcass composition, DDGS, growing-finishing pigs, growth performance, NE prediction