Table 7.
Effect of corn silage and modified distillers grains with solubles (MDGS) inclusion on pH and ruminal volatile fatty acid measurements (Exp. 3)
| Treatment1 | P-value2 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Item | 95:0 | 15:20 | 45:20 | 15:40 | 45:40 | SEM | F-test | Int. | Silage | MDGS |
| Ruminal pH | ||||||||||
| Maximum pH | 7.24a | 6.65bc | 6.77b | 6.58c | 7.02b | 0.18 | < 0.01 | 0.49 | 0.04 | 0.88 |
| Average pH | 6.69a | 5.72cd | 5.99bc | 5.67d | 6.20b | 0.18 | < 0.01 | 0.35 | 0.01 | 0.41 |
| Minimum pH | 5.94a | 5.01c | 5.22bc | 5.06c | 5.36b | 0.14 | < 0.01 | 0.55 | 0.03 | 0.31 |
| Magnitude | 1.30b | 1.64a | 1.55a | 1.52a | 1.67a | 0.15 | 0.02 | 0.98 | 0.70 | 0.16 |
| Variance | 0.12 | 0.22 | 0.18 | 0.13 | 0.16 | 0.06 | 0.20 | 0.80 | 0.95 | 0.13 |
| Time < 5.6, min/d | 7c | 690a | 335b | 752a | 212bc | 149 | < 0.01 | 0.61 | < 0.01 | 0.57 |
| Area < 5.63 | 1b | 247a | 92ab | 215a | 39b | 84 | 0.04 | 0.81 | 0.06 | 0.42 |
| Ruminal VFA 4 | ||||||||||
| Total, mM | 91.3c | 113.2a | 106.6b | 102.1b | 95.0bc | 6.5 | < 0.01 | 0.61 | 0.01 | 0.03 |
| Acetate5 | 59.2a | 50.1c | 54.0b | 48.3c | 53.0b | 1.7 | < 0.01 | 0.31 | < 0.01 | 0.54 |
| Propionate5 | 28.5c | 35.3a | 31.5b | 38.2a | 30.4bc | 2.3 | < 0.01 | 0.11 | < 0.01 | 0.68 |
| Butyrate5 | 9.4bc | 11.6ab | 11.3bc | 10.4c | 12.9a | 1.7 | < 0.01 | < 0.01 | 0.07 | 0.51 |
| A:P6 | 2.26a | 1.53c | 1.86b | 1.40c | 1.85b | 0.16 | < 0.01 | 0.95 | 0.01 | 0.31 |
Within a row, values lacking common superscripts differ when F-test was significant (P < 0.10).
95:0 = 95% corn silage, 0% MDGS; 15:20 = 15% Corn Silage, 20% MDGS; 15:40 = 15% Corn Silage, 40% MDGS; 45:20 = 45% Corn Silage, 20% MDGS; 45:40 = 45% Corn Silage, 40% MDGS.
F-test = P-value for the overall F-test of all diets. Int. = P-value for the interaction of corn silage × MDGS. Silage = P-value for the main effect of corn silage inclusion. MDGS = P-value for the main effect of MDGS inclusion.
Area < 5.6 = ruminal pH units below 5.6 by minute.
Ruminal volatile fatty acids (VFA).
VFA concentraton in mol/100 mol.
Acetate:Propionate.