Table 1.
Methane production (g/d) and yield (g/kg DMI) estimated from measurements during mealtime at the feed bin and from 24 CH4 measurements in growing heifers fed ad libitum alfalfa silage in respiration chambers
| Item | Mean | SD | Maximum | Minimum | CV |
|---|---|---|---|---|---|
| 24-h CH41 (g/d) | 262 | 24.0 | 319 | 226 | 9.2 |
| 24-h CH4 (g/kg of DMI) | 25.3 | 2.15 | 29.0 | 20.8 | 8.5 |
| Mealtime CH4 (g/d) | 276 | 22.7 | 313 | 241 | 8.2 |
| Mealtime CH4 (g/kg of DMI) | 25.8 | 3.07 | 35.3 | 20.8 | 11.9 |
1
The 24-h measured CH4 production was calculated by averaging all ~3-min CH4 values recorded in a 24-h period by the chamber system.