View Full Table | Close Full ViewTable 1.

Composition of experimental diets (as-fed basis)

 
Exp. 1
Exp. 2
Cereals — soybean meal — free AA
Cereals — free AA
Item 19.7% CP1 16.8% CP1 14.0% CP1 12.7% CP1 17.6% CP1 15.6% CP1 13.5% CP1 11.8% CP1 13.0% CP1 14.0% CP1
Ingredients, %
    Wheat 16.04 17.90 19.92 20.83 19.37 23.58 30.54 32.76 50.00 50.00
    Barley 16.04 17.90 19.92 20.83 19.37 23.58 30.54 32.76 28.40 28.40
    Corn 32.08 35.80 39.83 41.65 12.91 15.72 20.36 21.84
    Soybean meal 26.93 18.85 9.27 4.88 25.19 18.52 8.56 1.97
    Corn starch 4.00 4.00 4.00 4.00 15.00 10.06 8.10 6.29
    Sunflower oil 1.00 1.00 1.00 1.00 3.00 3.00 2.96 2.21 1.46 1.56
    l-Lys HCl 0.34 0.59 0.90 1.04 0.28 0.46 0.73 0.92 1.00 1.00
    l-Thr 0.13 0.25 0.40 0.46 0.12 0.20 0.31 0.40 0.45 0.45
    l-Trp 0.05 0.09 0.14 0.17 0.43 0.06 0.10 0.13 0.14 0.14
    dl-Met 0.13 0.21 0.31 0.35 0.12 0.16 0.21 0.27 0.32 0.32
    l-Val 0.15 0.32 0.39 0.09 0.21 0.32 0.39 0.39
    l-His 0.10 0.15 0.06 0.12 0.17 0.17
    l-Ile 0.18 0.27 0.11 0.22 0.28 0.28
    l-Leu 0.25 0.37 0.18 0.34 0.54 0.54
    l-Phe 0.22 0.37 0.10 0.29 0.43 0.43
    l-Arg 0.08 0.08
    l-Glu 1.88 3.59
    l-Gly 0.56 0.56
    l-Pro 0.20 0.20
    Phytase 0.01 0.01 0.01 0.01 0.02 0.02
    Sodium bicarbonate 0.09 0.39 0.81 1.15 1.30 1.30
    Salt 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45
    Calcium carbonate 1.10 1.10 1.10 1.10 1.97 2.02 2.08 2.13 2.14 2.14
    Dicalcium phosphate 1.20 1.20 1.20 1.20 1.20 1.20 1.20 1.20 1.20 1.20
    Vitamin and mineral premix2 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50
Analyzed composition,3 %
    CP 19.44 16.55 13.95 12.73 17.36 15.33 13.39 11.61 12.50 13.35
    Ether extract 3.71 3.59 3.59 3.41 4.16 4.23 3.24 2.14 2.13 2.39
    Crude Fiber 3.25 2.97 2.62 2.41 2.89 2.68 2.64 2.49 2.13 2.11
    NDF 12.45 11.06 10.08 9.29 10.21 11.60 10.55 9.29 7.99 8.01
    ADF 3.66 3.49 2.95 2.55 3.81 4.01 3.66 3.14 2.72 2.80
    ADL 0.64 0.67 0.69 0.54 0.24 0.40 0.39 0.38 0.40 0.35
    Lys 1.27 1.27 1.25 1.19 1.07 1.03 0.99 0.95 0.98 0.98
    Thr 0.80 0.80 0.69 0.72 0.72 0.70 0.69 0.65 0.64 0.64
    Met 0.40 0.43 0.52 0.52 0.33 0.34 0.36 0.39 0.41 0.41
    Met +     Cys 0.69 0.69 0.73 0.71 0.58 0.59 0.58 0.57 0.57 0.57
    Trp 0.28 0.27 0.26 0.26 0.56 0.24 0.21 0.19 0.21 0.21
    Ile 0.81 0.65 0.62 0.63 0.70 0.60 0.55 0.54 0.52 0.52
    Val 0.90 0.88 0.85 0.85 0.80 0.78 0.75 0.72 0.70 0.71
    Leu 1.52 1.28 1.23 1.23 1.28 1.12 1.05 1.00 0.98 1.00
    His 0.48 0.39 0.39 0.38 0.40 0.35 0.31 0.29 0.30 0.31
    Phe 0.95 0.78 0.78 0.83 0.83 0.72 0.66 0.68 0.74 0.75
    Tyr 0.66 0.53 0.39 0.32 0.57 0.48 0.38 0.28 0.23 0.22
    Arg 1.20 0.95 0.66 0.52 1.03 0.88 0.64 0.46 0.43 0.43
    Ala 0.87 0.74 0.58 0.51 0.73 0.64 0.52 0.42 0.29 0.29
    Asp 1.83 1.43 0.93 0.74 1.60 1.31 0.90 0.58 0.42 0.42
    Glu 3.57 3.02 2.33 2.06 3.33 2.97 2.56 2.14 3.67 5.18
    Gly 0.78 0.64 0.47 0.40 0.71 0.61 0.49 0.37 0.82 0.82
    Ser 0.91 0.76 0.54 0.47 0.81 0.70 0.55 0.42 0.36 0.36
    Pro 1.19 1.05 0.89 0.79 1.02 0.96 0.90 0.81 0.89 0.89
Calculated composition3
    NE,4 MJ/kg 9.92 10.22 10.54 10.58 10.25 10.30 10.30 10.33 10.55 10.77
    SID Lys,5 % 1.15 1.16 1.17 1.12 0.96 0.94 0.92 0.89 0.92 0.93
    Dig N:SID Lys,5 % 2.30 1.94 1.63 1.55 2.46 2.20 1.96 1.76 1.91 2.04
    EB5, mEq/kg 182 130 69 41 180 180 180 180 180 180
1Expected CP content.
2Supplied per kilogram of diet (as-fed basis): vitamin A, 10,000 IU; vitamin D3, 2,000 IU; vitamin E, 20 mg; vitamin K3, 2 mg; vitamin B1, 2 mg; vitamin B2, 5 mg; niacin, 20 mg; pantothenic acid, 10 mg; vitamin B6, 5 mg; biotin, 0.2 mg; folic acid, 1 mg; vitamin B12, 0.03 mg; chloride de choline, 600 mg; vitamin, 40 mg; Fe as iron sulfate, 100 mg; Cu as copper sulfate, 20 mg; Zn as zinc oxide, 100 mg; Mn as manganese oxide, 40 mg; I as calcium iodate, 0.6 mg; Se as sodium selenite, 0.3 mg; and Co as cobalt carbonate, 1 mg.
3Adjusted for 87.3% DM.
4Values for NE were calculated according to Noblet et al. (1994).
5SID Lys = standardized ileal digestible Lys; Dig N = fecal digestible N, calculated from the analyzed Lys and N content, the fecal N digestibility, and ileal Lys digestibility of the feed ingredients (Sauvant et al., 2004); EB = electrolyte balance calculated from the feed ingredients (Sauvant et al., 2004).



View Full Table | Close Full ViewTable 2.

Effect of reducing the dietary CP content on the N balance in 10- to 20-kg pigs (Exp. 1)1

 
CP, %
Item 19.7 16.8 14.0 12.7 RSD2 P-value
Initial BW, kg 11.5 11.9 11.8 11.7 0.8 0.90
Final BW, kg 16.5 16.4 16.0 15.7 0.9 0.56
ADFI,3 g/d 513 529 524 525 24 0.46
ADG,3 g/d 375a 364a 323b 305b 41 <0.01
G:F,3 g/g 0.73a 0.69a,b 0.62bc 0.58c 0.10 <0.01
Nitrogen balance
    Ingested, g/d 15.5a 13.8b 11.5c 10.5d 0.8 <0.01
    Absorbed, g/d 13.3a 11.7b 9.7c 9.0d 0.7 <0.01
    Retained, g/d 9.9a 9.8a 8.3b 7.5c 0.8 <0.01
    Digestibility, % 85.8 84.8 84.3 85.7 2.3 0.47
    Retained, % of intake 63.9a 71.0b 72.2b 71.4b 4.1 <0.01
    Retained, % of absorbed 74.4a 83.8b 85.6b 83.3b 3.7 <0.01
a–cWithin a row, values with different superscripts are different (P < 0.05).
1Data are presented as least squares means with 6 pigs per treatment.
2RSD = residual SD, which is the root-mean-square of the error that applies to the whole model.
3Adjusted for 87.3% DM.



View Full Table | Close Full ViewTable 3.

Effect of reducing the dietary CP content on performance in 10- to 20-kg pigs (Exp. 2)1

 
Cereals — soybean meal — free AA Cereals — free AA
Item 17.6% CP 15.6% CP 13.5% CP 11.8% CP 13.0% CP 14.0% CP RSD2 P-value
Initial BW, kg 12.7 12.7 12.6 12.6 13.0 12.8 0.6 0.60
Final BW, kg 22.2a 22.2a 21.9a 20.1b 21.8a 22.3a 1.7 <0.01
ADFI,3 g/d 766 775 779 734 810 782 96 0.55
ADG,3 g/d 450a 454a 442a 358b 420a 451a 67 <0.01
G:F,3 g/g 0.59a 0.59a 0.57a 0.49b 0.52b 0.58a 0.06 <0.01
a,bWithin a row, values with different superscripts are different (P < 0.05).
1Data are presented as least squares means with 14 pigs per treatment.
2RSD = residual SD, which is the root-mean-square of the error that applies to the whole model.
3Adjusted for 87.3% DM.