Table 4.
Mean response ratio and estimated heterogeneity parameters describing the short-term effects (<28 days of treatment) of supplementing an essential oil blend (1 g/d) to dairy cows.
| Parameter 1 | n | Response Ratio(R) |
95% CI | p-value | Heterogeneity | |
|---|---|---|---|---|---|---|
| Min.–Max. | I 2 | Q | ||||
| DMI (kg/d) | 17 | 1.000 | 0.976–1.024 | 0.988 | 84 | <0.001 |
| Milk yield (kg/d) | 19 | 1.026 | 1.006–1.046 | 0.008 | 76 | <0.001 |
| Milk Fat (g/kg) | 10 | 1.000 | 0.978–1.022 | 0.999 | 76 | <0.001 |
| Milk protein (g/kg) | 10 | 1.002 | 0.991–1.012 | 0.731 | 55 | 0.018 |
| Milk SCC (log/mL) | 3 | 1.036 | 0.984–1.090 | 0.177 | 0 | 0.910 |
| FPCM yield (kg/d) | 16 | 1.028 | 1.009–1.047 | 0.004 | 69 | <0.001 |
| FCE (kg/kg) | 15 | 1.010 | 0.989–1.029 | 0.348 | 40 | 0.055 |
| Rumen pH | 3 | 1.007 | 0.991–1.023 | 0.385 | 0 | 0.445 |
| Total VFA (mmol/L) | 9 | 0.973 | 0.936–1.010 | 0.158 | 4 | 0.400 |
| Acetate (%) | 7 | 1.005 | 0.998–1.011 | 0.116 | 22 | 0.260 |
| Propionate (%) | 7 | 1.009 | 0.969–1.049 | 0.672 | 39 | 0.131 |
| Butyrate (%) | 7 | 0.985 | 0.958–1.012 | 0.276 | 0 | 0.544 |
| Protozoa (log cells/mL) | 3 | 0.969 | 0.896–1.046 | 0.423 | 78 | 0.011 |
| CH4 production (g/d) | 8 | 0.978 | 0.957–0.998 | 0.037 | 0 | 0.675 |
| CH4 yield (g/kg DMI) | 8 | 0.980 | 0.923–1.039 | 0.497 | 49 | 0.047 |
| CH4 intensity (g/kg FPCM) | 7 | 0.974 | 0.944–1.003 | 0.087 | 0 | 0.984 |
1 DMI, dry matter intake; SCC, somatic cell counts; FPCM, fat and protein corrected milk; FCE, feed conversion efficiency; VFA, volatile fatty acids; AI, artificial inseminations.