Table 3. Description of gas emission, rumen fermentation characteristics, and performances in beef and dairy cattle database
Parameter | Parameter estimates |
n | Mean | SD | Median | MIN | MAX |
Beef | | | | | | |
CH4 (g/kg DMI) | 36 | 17.52 | 6.031 | 17.85 | 3.10 | 28.20 |
pH | 14 | 6.46 | 0.249 | 6.45 | 6.13 | 6.96 |
Total VFA (mM) | 18 | 112.61 | 25.142 | 104.65 | 74.50 | 160.50 |
Acetate (%) | 18 | 58.41 | 8.498 | 59.65 | 44.10 | 74.40 |
Propionate (%) | 18 | 23.49 | 7.216 | 21.00 | 15.90 | 42.60 |
Butyrate (%) | 18 | 12.28 | 3.475 | 12.95 | 5.00 | 17.80 |
Iso-butyrate (%) | 18 | 1.11 | 0.180 | 1.07 | 0.88 | 1.52 |
Valerate (%) | 18 | 1.92 | 0.552 | 1.84 | 1.20 | 3.19 |
Iso-valerate (%) | 18 | 2.08 | 0.558 | 1.97 | 1.20 | 3.18 |
A:P ratio | 18 | 2.85 | 0.998 | 2.89 | 1.06 | 4.70 |
DMI (kg/d) | 36 | 9.09 | 1.751 | 9.13 | 6.05 | 12.10 |
Dairy | | | | | | |
CH4 (g/kg DMI) | 17 | 16.81 | 4.560 | 17.80 | 7.18 | 23.50 |
pH | 8 | 6.37 | 0.106 | 6.38 | 6.20 | 6.50 |
Total VFA (mM) | 10 | 99.22 | 8.424 | 99.95 | 85.80 | 109.00 |
Acetate (%) | 10 | 57.70 | 4.195 | 57.94 | 52.10 | 65.70 |
Propionate (%) | 10 | 22.53 | 2.144 | 22.39 | 19.30 | 26.40 |
Butyrate (%) | 10 | 14.13 | 1.380 | 14.21 | 11.10 | 15.90 |
Iso-butyrate (%) | 10 | 0.94 | 0.238 | 1.00 | 0.57 | 1.19 |
Valerate (%) | 10 | 2.03 | 0.331 | 2.09 | 1.57 | 2.57 |
Iso-valerate (%) | 10 | 1.63 | 0.768 | 1.93 | 0.66 | 2.58 |
A:P ratio | 10 | 2.65 | 0.455 | 2.64 | 2.02 | 3.51 |
DMI (kg/d) | 17 | 22.22 | 3.732 | 21.30 | 18.30 | 28.00 |
Milk yield (kg/d) | 17 | 32.69 | 7.803 | 28.20 | 25.80 | 46.40 |
Milk fat (%) | 17 | 3.93 | 0.332 | 4.02 | 3.31 | 4.35 |
Milk protein (%) | 17 | 3.28 | 0.198 | 3.19 | 3.06 | 3.61 |
Milk lactose (%) | 14 | 4.61 | 0.195 | 4.65 | 4.26 | 4.81 |
FCM (kg/d) | 17 | 32.25 | 8.143 | 29.00 | 23.90 | 46.41 |
SD, standard deviation; MIN, minimum value in database; MAX, maximum value in database; CH4, methane; DMI, dry matter intake; H2, hydrogen; CO2, carbon dioxide; VFA, volatile fatty acids; A:P ratio, acetate to propionate ratio; FCM, fat corrected milk.