283
Effect of Increasing Sid Trp:Lys Ratio on Growth Performance of Grower-Finisher Pigs
Wednesday, March 15, 2017: 11:15 AM
214 (Century Link Center)
Tsung-Cheng Tsai
,
Department of Animal Science, Division of Agriculture, University of Arkansas, Fayetteville, AR
HaeJin Kim
,
University of Arkansas, Fayetteville, AR
Xiaofan Wang
,
Department of Animal Science, Division of Agriculture, University of Arkansas, Fayetteville, AR
J. J. Chewning
,
Swine Research Services, Inc., Springdale, AR
Jason A. Apple
,
Department of Animal Science, University of Arkansas Division of Agriculture, Fayetteville, AR
John E. Thomson
,
Evonik Degussa Corp, Kennesaw, GA
Charles V. Maxwell
,
Department of Animal Science, Division of Agriculture, University of Arkansas, Fayetteville, AR
Using a 5-phase feeding regime, pigs (n=252) were fed either antibiotic-free, control diets formulated to meet 100% SID Lys requirements and an SID Trp:Lys of 18.5 or diets formulated to 93% SID Lys requirements and incorporating L-Trp at 2.5 percentage unit increments to achieve SID Trp:Lys of 13.5, 16.0, 18.5, 21.0, or 23.5 during phase 1 (25 to 39 kg), 3 (71 to 86 kg), and 5 (110 to 140 kg) to determine the optimum SID Trp:Lys requirements. All pigs received a common corn-SBM-CDDGS-based, antibiotic-free, nutrient-adequate diets during feeding phase 2 and 4, and 10 ppm ractopamine hydrochloride was included in all phase-5 diets. ADG, ADFI, and BW increased quadratically, with the greatest responses observed in pigs fed SID Trp:Lys of 21 during phase 1 and 3, while the greatest ADG and BW at 18.5 and greatest ADFI at 16.0 during phase 5. G:F was similar in phase 1 and 3, but increased linearly with greatest result showed in pigs fed 23.5 of SID Trp/Lys diet in phase 5. HCW increased quadratic in pigs fed to an SID Trp:Lys 16.0, but 10
th rib fat depth and lean yield were similar among treatments. The optimum ADG was predicted to be 0.72, 0.75, 1.12 kg/d in pigs fed an SID Trp:Lys ratio of 18.2, 18.8 and 16.8 in phases 1, 3, and 5, respectively.
|
93% SID Lys
|
100% SID Lys
|
|
|
|
13.50%
|
16%
|
18.50%
|
21%
|
23.50%
|
18.50%
|
Linear
|
Quad.
|
Phase 1 ADG, kg/d
|
0.64
|
0.70
|
0.71
|
0.73
|
0.72
|
0.59
|
< 0.01
|
0.04
|
Phase 3 ADG, kg/d
|
0.65
|
0.72
|
0.74
|
0.75
|
0.70
|
0.80
|
0.26
|
0.07
|
Phase 5 ADG, kg/d
|
0.90
|
1.07
|
1.12
|
1.08
|
1.09
|
1.08
|
< 0.01
|
< 0.01
|
Phase 1 ADFI, kg/d
|
1.29
|
1.40
|
1.50
|
1.59
|
1.38
|
1.44
|
0.16
|
0.04
|
Phase 3 ADFI, kg/d
|
2.27
|
2.68
|
2.65
|
2.77
|
2.60
|
2.72
|
0.08
|
0.05
|
Phase 5 ADFI, kg/d
|
3.08
|
3.52
|
3.31
|
3.47
|
3.30
|
3.35
|
0.36
|
0.09
|
Phase 5 G:F
|
0.29
|
0.31
|
0.33
|
0.31
|
0.33
|
0.32
|
< 0.01
|
0.41
|
End of phase 1 BW, kg
|
37.76
|
39.09
|
39.25
|
39.73
|
39.48
|
36.67
|
< 0.01
|
0.04
|
End of phase 3 BW, kg
|
84.70
|
86.23
|
86.93
|
87.10
|
85.97
|
88.79
|
0.20
|
0.07
|
End of phase 5 BW, kg
|
134.50
|
140.21
|
141.39
|
139.89
|
139.87
|
141.70
|
0.02
|
0.01
|
HCW, kg
|
220.63
|
229.44
|
229.27
|
229.00
|
229.07
|
231.07
|
0.03
|
0.05
|
Lean, %
|
53.24
|
53.49
|
53.02
|
53.59
|
53.35
|
53.31
|
0.76
|
0.96
|
10th rib fat depth, mm
|
21.44
|
22.08
|
22.18
|
21.10
|
20.93
|
22.83
|
0.50
|
0.43
|