Table 3.
Mean response ratio and estimated heterogeneity parameters describing the overall effects of supplementing an essential oil blend (1 g/d per cow) to dairy cows.
| Parameter 1 | n | Response Ratio (R) |
95% CI | p-Value | Heterogeneity | |
|---|---|---|---|---|---|---|
| Min. Max. | I 2 | Q | ||||
| DMI (kg/d) | 16 | 1.003 | 0.985-1.020 | 0.737 | 86 | <0.001 |
| Milk yield (kg/d) | 23 | 1.020 | 1.011-1.028 | <0.001 | 16 | 0.248 |
| Milk Fat (g/d) | 16 | 1.004 | 0.979-1.029 | 0.739 | 85 | 0.000 |
| Milk protein (g/kg) | 16 | 1.002 | 0.996-1.008 | 0.419 | 46 | 0.023 |
| Milk lactose (g/kg) | 8 | 0.998 | 0.992-1.003 | 0.519 | 76 | <0.001 |
| Milk SCC (log/mL) | 3 | 0.994 | 0.944-1.045 | 0.800 | 69 | 0.040 |
| FPCM yield (kg/d) | 20 | 1.031 | 1.026-1.035 | <0.001 | 0 | 0.995 |
| FCE (kg/kg) | 16 | 1.030 | 1.011-1.049 | 0.002 | 34 | 0.087 |
| Rumen pH | 3 | 1.006 | 0.989-1.022 | 0.476 | 0 | 0.511 |
| Total VFA (mmol/L) | 8 | 0.982 | 0.946-1.019 | 0.346 | 0 | 0.685 |
| Acetate (%) | 7 | 1.002 | 0.991-1.011 | 0.756 | 91 | <0.001 |
| Propionate (%) | 7 | 1.011 | 0.945-1.082 | 0.744 | 97 | <0.001 |
| Butyrate (%) | 7 | 0.991 | 0.963-1.019 | 0.525 | 7 | 0.377 |
| Protozoa (log cells/mL) | 3 | 0.977 | 0.924-1.032 | 0.405 | 39 | 0.193 |
| CH4 production (g/d) | 8 | 0.954 | 0.921-0.987 | 0.007 | 23 | 0.241 |
| CH4 yield (g/kg DMI) | 8 | 0.982 | 0.918-1.050 | 0.600 | 42 | 0.088 |
| CH4 intensity (g/kg FPCM) | 8 | 0.925 | 0.864-0.989 | 0.023 | 19 | 0.278 |
1 DMI, dry matter intake; SCC, somatic cell counts; FPCM, fat and protein corrected milk; FCE, feed conversion efficiency; VFA, volatile fatty acids