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Ingredient and chemical composition of basal experimental diet

 
Item Composition1
Ingredient composition
    Dry rolled corn 39.0
    Earlage 32.1
    Wet distiller’s grains 21.2
    Corn silage 3.2
    Supplement2 2.6
    Urea premix3 2.0
Chemical composition
Crude protein 15.9
    NDF 20.6
    ADF 8.6
    Lignin 1.0
    Ash 5.3
    Starch 45.8
    Crude fat 5.1
Diet NEg, Mcal/kg4 1.4
1Composition as % of 100 °C DM.
2Supplement contained (DM basis): monensin, 0.8 g/kg; Ca, 25%; P, 0.1%; NaCl, 7%; K, 3%; Co, 10 mg/kg; Cu, 350 mg/kg; Se, 9 mg/kg; Zn, 1750 mg/kg; vitamin A 15,000 IU/kg; vitamin D3, 29,000 IU/kg; vitamin E, 165 IU/kg; Thiamine, 500 mg/kg.
3Premix contained (DM basis): soybean meal, 714 g/kg; urea 286 g/kg.
4Estimated using Nutrient Requirements for Beef Cattle (NRC, 2000).



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Fatty acid and amino acid composition of the basal diet

 
Item Composition1
Total fatty acids, g/100 g of DM 4.9
Individual fatty acids, g /100 g of total FA
    C16:0 14.5
    C18:0 1.8
        Total C18:1 23.1
        trans-C18:1 23.1
        cis-C18:1 0.0
    C18:2 50.0
        C18:2, conjugated 0.0
    C18:3 1.5
    Other 8.1
Total amino acids, mg/g of DM 125.7
Essential amino acids, mg/g of DM
    Threonine 4.9
    Valine 6.7
    Methionine 2.7
    Isoleucine 5.0
    Leucine 14.8
    Phenylalanine 6.6
    Histidine 3.1
    Lysine 4.3
    Arginine 5.7
Nonessential amino acids, mg/g of DM
    Aspartic acid 9.4
    Serine 5.8
    Glutamic acid 22.1
    Proline 10.0
    Glycine 5.4
    Alanine 9.8
    Cysteine 2.3
    Tyrosine 4.8
Other amino acids, mg/g of DM1 2.3
1Composition, g/g of other amino acids: taurine, 0.33; hydroxyproline, 0.14; hydroxylysine, 0.43; ornithine, 0.10.



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Effect of bismuth subsalicylate and dietary sulfur level on DM, OM and fiber digestion in continuous culture

 
Treatment1
Low sulfur
High sulfur
P-value
Item, g/100 g CON BSS CON BSS SEM2 BSS Sulfur B × S
DM, apparent 47.1 39.2 50.3 39.3 1.4 < 0.01 0.31 0.38
DM, true3 64.1 46.9 67.9 47.6 2.5 < 0.01 0.13 0.33
OM, apparent 37.5 26.9 41.4 28.2 1.8 < 0.01 0.13 0.46
OM, true3 52.8 34.1 57.2 35.9 2.7 < 0.01 0.13 0.33
NDF 19.3 27.5 24.4 30.0 4.5 0.15 0.41 0.77
ADF 32.1 35.0 36.7 38.2 2.9 0.47 0.21 0.81
1Treatments were arranged in a 2 × 2 factorial design, with dietary sulfur at 0.12 (low sulfur) or 0.42 (high sulfur) % of diet DM, and bismuth subsalicylate at 0 (CON) and 0.5 (BSS) % of diet DM. High sulfur level was achieved by addition of sodium sulfate to the basal diet.
2Standard error of the mean, n = 4 observations per treatment.
3Corrected for microbial contribution.



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Effect of bismuth subsalicylate and dietary sulfur level on VFA concentration and nitrogen metabolism in continuous culture

 
Treatment1
Low sulfur
High sulfur
P-value
Item CON BSS CON BSS SEM2 BSS Sulfur B × S
Total VFA, mM 107.0 49.7 122.3 50.1 9.7 < 0.01 0.39 0.42
Individual VFA, mol/100mol
    Acetate 34.5 27.5 34.5 29.8 1.2 0.01 0.56 0.57
    Propionate 36.1 13.8 39.0 20.7 3.4 < 0.01 0.27 0.65
    Butyrate 14.4 33.3 13.7 25.9 2.5 < 0.01 0.19 0.27
    Isobutyrate 0.12 0.03 0.15 0.10 0.02 0.15 0.27 0.61
    Isovalerate 0.15 0.0 0.11 0.0 0.03 < 0.01 0.62 0.62
Branched-chain VFA, mM 0.28 0.01 0.36 0.04 0.05 < 0.01 0.46 0.78
A:P Ratio 0.99 2.16 0.98 1.47 0.15 < 0.01 0.12 0.12
1Treatments were arranged in a 2 × 2 factorial design, with dietary sulfur at 0.12 (low sulfur) or 0.42 (high sulfur) % of diet DM, and bismuth subsalicylate at 0 (CON) and 0.5 (BSS) % of diet DM. High sulfur level was achieved by addition of sodium sulfate to the basal diet.
2Standard error of the mean, n = 4 observations per treatment.



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Effect of bismuth subsalicylate (BSS) and dietary sulfur level on fermentation pH in continuous culture

 
Treatment1
Low sulfur
High sulfur
P-value
Item CON BSS CON BSS SEM2 BSS Sulfur B × S
Mean pH3 5.23 5.75 5.25 5.72 0.02 < 0.01 0.77 0.26
Minimum pH3 5.17 5.70 5.19 5.68 0.03 < 0.01 0.95 0.50
Maximum pH3 5.30 5.80 5.32 5.77 0.02 < 0.01 0.81 0.20
Time above pH 5.64 0.1 99.1 0.0 88.4 11.2 < 0.01 0.31 0.37
Time between pH 5.2 and 5.64 74.3 0.9 76.2 11.6 21.2 < 0.01 0.58 0.68
Time below pH 5.24 25.6 0.0 23.8 0.0 17.9 0.03 0.93 0.93
1Treatments were arranged in a 2 × 2 factorial design, with dietary sulfur at 0.12 (low sulfur) or 0.42 (high sulfur) % of diet DM, and bismuth subsalicylate at 0 (CON) and 0.5 (BSS) % of diet DM. High sulfur level was achieved by addition of sodium sulfate to the basal diet.
2Standard error of the mean.
3Analyzed as repeated measures with 1 observation-1 × fermenter-1 × hour during 3 consecutive sampling days.
4Expressed as percent of total time over 3 consecutive sampling days, n = 4 replicates per treatment.



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Effect of bismuth subsalicylate and dietary sulfur level on nitrogen metabolism in continuous culture

 
Treatment1
Low sulfur
High sulfur
P-value
Item CON BSS CON BSS SEM2 BSS Sulfur B × S
NH3-N, mg/dL 2.7 20.8 2.4 19.9 2.3 < 0.01 0.37 0.67
N flow, g/d
    NH3-N 0.05 0.40 0.05 0.38 0.04 < 0.01 0.36 0.69
    Non NH3-N 2.10 1.72 2.06 1.67 0.05 < 0.01 0.21 0.88
    Microbial-N 1.10 0.50 1.09 0.52 0.08 < 0.01 0.78 0.67
    Dietary-N 1.00 1.22 0.97 1.15 0.03 0.02 0.32 0.69
CP degradation, % 47.6 36.2 49.4 40.0 2.4 < 0.01 0.28 0.69
EMPS3 29.3 20.6 26.8 20.7 0.8 < 0.01 0.14 0.13
1Treatments were arranged in a 2 × 2 factorial design, with dietary sulfur at 0.12 (low sulfur) or 0.42 (high sulfur) % of diet DM, and bismuth subsalicylate at 0 (CON) and 0.5 (BSS) % of diet DM. High sulfur level was achieved by addition of sodium sulfate to the basal diet.
2Standard error of the mean, n = 4 observations per treatment.
3EMPS: Efficiency of microbial protein synthesis (g of microbial N/kg of OM truly digested).



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Effect of bismuth subsalicylate (BSS) and dietary sulfur level on amino acid flow from fermenters1

 
Treatment2
Low sulfur
High sulfur
P-value
Amino acid CON BSS CON BSS SEM3 BSS Sulfur B × S
Essential flow, mg/d
    Threonine 528.2 396.3 498.8 394.0 11.5 < 0.01 0.24 0.34
    Valine 667.3 551.4 634.8 538.0 11.2 < 0.01 0.18 0.66
    Methionine 262.4 197.3 246.5 197.0 7.2 < 0.01 0.42 0.45
    Isoleucine 554.2 435.1 528.9 424.2 9.8 < 0.01 0.20 0.70
    Leucine 1334.8 1152.2 1257.3 1137.9 26.0 < 0.01 0.18 0.39
    Phenylalanine 638.2 514.4 598.2 509.4 11.5 < 0.01 0.15 0.28
    Histidine 253.9 237.9 242.9 231.2 4.8 0.03 0.19 0.85
    Lysine 513.8 431.4 537.2 415.3 20.6 < 0.01 0.83 0.36
    Arginine 510.8 433.3 504.0 422.6 12.6 < 0.01 0.62 0.77
Nonessential flow, mg/d
    Aspartic acid 1077.0 792.7 1029.5 785.9 20.4 < 0.01 0.31 0.50
    Serine 540.3 423.9 510.1 428.6 14.2 < 0.01 0.47 0.32
    Glutamic acid 1919.7 1690.9 1797.2 1667.2 32.2 < 0.01 0.10 0.29
    Proline 743.1 726.7 685.6 704.5 14.4 0.96 0.04 0.39
    Glycine 541.9 427.8 510.7 424.5 11.0 < 0.01 0.24 0.36
    Alanine 931.4 759.6 883.6 767.4 14.5 < 0.01 0.36 0.20
    Cysteine 168.1 171.5 153.4 166.2 3.0 0.02 0.01 0.22
    Tyrosine 514.6 403.7 487.5 399.1 9.9 < 0.01 0.22 0.43
1Daily outflows calculated as effluent DM outflow x amino acid concentration of effluent.
2Treatments were arranged in a 2 × 2 factorial design, with dietary sulfur at 0.12 (low sulfur) or 0.42 (high sulfur) % of diet DM, and bismuth subsalicylate at 0 (CON) and 0.5 (BSS) % of diet DM. High sulfur level was achieved by addition of sodium sulfate to the basal diet.
3Standard error of the mean, n = 4 observations per treatment.



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Effect of bismuth subsalicylate (BSS) and dietary sulfur level on fatty acid flows from fermenters

 
Treatment1
Low sulfur
High sulfur
Item CON BSS CON BSS SEM2
Total fatty acid intake, mg/d3 3708.1 3699.0 3697.2 3699.7 -
Individual fatty acid intake, mg/d
    C16:0 539.1 537.8 537.5 537.9 -
    C18:0 66.7 66.5 66.5 66.5 -
    C18:1 857.1 855.0 854.5 855.1 -
    C18:2 1855.8 1851.1 1850.2 1851.4 -
    C18:3 55.9 55.8 55.7 55.8 -
    Other 298.9 298.2 298.0 298.2 -
Total fatty acid outflow, mg/da,4 3124.5 3899.9 2904.2 3421.3 183.5
    C16:0 a 476.0 623.3 404.0 499.0 53.2
    C18:0c 206.8d 72.8d 396.5e 64.0d 45.3
    C18:1a,b 1630.9 943.2 1388.4 862.4 58.3
    C18:2a,b 617.6 2052.1 550.7 1850.1 59.1
    C18:3a 16.8 78.5 15.6 56.5 9.2
    Othera,b 130.4 82.4 111.5 54.8 11.3
Biohydrogenation intermediates
    Total trans-C18:1c 1026.9f 7.2d 872.1e 9.6d 35.4
        trans-8a 25.8 0.0 30.4 0.0 7.7
        trans-9a 10.3 0.0 22.5 0.5 6.6
        trans-10a 981.9 7.2 816.4 8.4 39.7
        trans-11 8.9 0.0 2.8 0.8 3.6
    Total cis-C18:1a,b 604.0 936.0 516.3 852.7 37.0
        cis-9a 552.4 693.4 345.5 828.0 133.8
        cis-10 6.2 213.8 131.9 0.0 123.7
        cis-11a 45.4 28.9 38.9 24.7 4.3
    C18:2 Conjugated 0.6 0.7 0.2 0.3 0.3
aMain effect of bismuth subsalicylate (P < 0.05).
bMain effect of dietary sulfur (P < 0.05).
cInteraction of bismuth subsalicylate and dietary sulfur (P < 0.05).
d–f Within a row, means without a common superscript differ (P < 0.05).
1Treatments were arranged in a 2 × 2 factorial design, with dietary sulfur at 0.12 (low sulfur) or 0.42 (high sulfur) % of diet DM, and bismuth subsalicylate at 0 (CON) or 0.5 (BSS) % of diet DM.
2Standard error of the mean, n = 4 observations per treatment.
3Daily intakes calculated as diet DM intake × fatty acid concentration of the diet.
4Daily outflows calculated as effluent DM outflow × fatty acid concentration of effluent.