Table 5. Equations for linear regression of ruminal fermentation parameters on 3-nitrooxypropanol levels (mg/kg of DMI) from ruminant database

Parameter Parameter estimates Model statistics
n intercept SE intercept p-value Slope SE slope p-value RMSE R2
Ruminal fermentation parameters
 pH 21 6.368 0.0643 < 0.0001 0.0007 0.00018 0.0071 0.048 0.678
 Total VFA (mM) 27 107.230 3.8455 < 0.0001 −0.0366 0.01090 0.0073 4.897 0.388
 Acetate (%) 29 61.303 2.0731 < 0.0001 −0.0310 0.00303 < 0.0001 0.875 0.898
 Propionate (%) 28 20.000 1.1388 < 0.0001 0.0128 0.00329 0.0031 1.250 0.448
 Butyrate (%) 28 12.364 0.6298 < 0.0001 0.0108 0.00333 0.0087 0.899 0.404
 Iso-butyrate (%) 28 1.004 0.0618 < 0.0001 0.0005 0.00019 0.0301 0.068 0.366
 Valerate (%) 28 1.719 0.1083 < 0.0001 0.0018 0.00038 0.0007 0.117 0.581
 Iso-valerate (%) 29 1.737 0.1595 < 0.0001 0.0021 0.00071 0.0135 0.217 0.381
 A:P ratio 28 3.153 0.2602 < 0.0001 −0.0034 0.00037 < 0.0001 0.110 0.884
 Ammonia (mg/dL) 26 10.606 1.9932 0.0005 −0.0112 0.00408 0.0228 1.658 0.001
 Bacteria1) 14 7.535 2.8407 0.0453 0.0068 0.00748 0.4157 1.211 0.052
 Methanogen2) 14 4.114 1.3232 0.0266 −0.0076 0.00288 0.0574 0.641 0.610
 Protozoa3) 12 2.426 0.4245 0.0046 0.0003 0.00270 0.9243 0.550 0.457
Animal performances
 DMI (g/kg) 50 12.074 1.5541 < 0.0001 −0.0017 0.00072 0.0304 0.329 0.170
 DMD (%) 13 68.022 2.6669 0.0001 0.0024 0.00559 0.6979 1.119 0.055
 OMD (%) 14 69.818 2.9233 0.0002 0.0047 0.00899 0.6359 1.273 0.086
 NDFD (%) 14 48.338 6.0701 0.0041 0.0111 0.01125 0.3952 1.944 0.123
1010/g of rumen digesta.
108/g of rumen digesta.
105/g of rumen digesta.
VFA, volatile fatty acids; A:P ratio, acetate to propionate ratio; DMI, dry matter intake; DMD, dry matter digestibility; OMD, organic matter digestibility; NDFD, neutral detergent fiber digestibility; SE, standard error; RMSE, residual mean square error; R2, coefficient of determination.