| Meta-regression analysis for the linear phase | Meta-analysis for the plateau phase | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Duration, wk | No. of trials | I2, % | Intercept | P-value | Coefficient | P-value | Adjusted R2, % | Duration, wk | No. of trials | I2, % | Pooled effect size | P-value | |
CH4 | ≤ 12 | 13 | 76.2 | −5.484 | 0.001 | 0.486 | 0.003 | 76.8 | ≥ 11 | 9 | 0.0 | 0.313 | 0.039 |
TVFA | ≤ 12 | 12 | 35.5 | −1.883 | 0.008 | 0.132 | 0.048 | 99.9 | ≥ 11 | 19 | 46.7 | −0.424 | <  0.001 |
Individual VFA molar proportion | Â | ||||||||||||
 Acetate | ≤ 11 | 11 | 76.8 | −4.086 | 0.004 | 0.563 | 0.004 | 76.7 | ≥ 7 | 22 | 47.5 | 0.748 | <  0.001 |
 Propionate | ≤ 11 | 11 | 84.5 | 7.306 | <  0.001 | −0.898 | <  0.001 | 92.2 | ≥ 7 | 22 | 51.2 | −0.366 | 0.033 |
 Butyrate | ≤ 11 | 11 | 80.6 | −7.059 | <  0.001 | 0.732 | 0.001 | 92.3 | ≥ 7 | 20 | 54.0 | −0.582 | 0.002 |
 A:P | ≤ 11 | 10 | 78.6 | −6.737 | 0.001 | 0.884 | 0.002 | 90.8 | ≥ 7 | 10 | 59.2 | 0.915 | 0.016 |
Total-tract fiber digestibility | Â | ||||||||||||
 NDF | ≤ 23 | 15 | 55.7 | −4.458 | <  0.001 | 0.153 | 0.005 | 85.0 |  |  |  |  |  |
 ADF | ≤ 23 | 11 | 69.8 | −6.276 | 0.001 | 0.213 | 0.030 | 45.1 |  |  |  |  |  |