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.