Table 2.
In vitro ruminal fermentation patterns.
| Item | Treatments | SEM | p-Value | Contrast | |||||
|---|---|---|---|---|---|---|---|---|---|
| CTL | NA1 | NA2 | CHI1 | CHI2 | L | Q | |||
| pH 1 | 6.8 ± 2.9E−8 | 6.9 ± 4.1E−8 | 6.8 ± 5.2E−8 | 6.8 ± 5.2E−8 | 6.7 ± 3.7E−8 | 1.8E−8 | 0.387 | 0.524 | 0.626 |
| N-NH3 (mg/dL) | 13.7 ± 0.07 c | 17.8 ± 0.16 a | 15.7 ± 0.16 b | 17.2 ± 0.35 a | 12.8 ± 0.19 c | 0.210 | <0.001 | <0.001 | 0.055 |
| Molar proportions of VFA (%) | |||||||||
| Acetic | 46.6 ± 0.01a | 40.9 ± 0.65 b | 40.7 ± 0.36 b | 41.9 ± 0.99 b | 43.1 ± 0.11 b | 0.555 | 0.003 | <0.001 | 0.004 |
| Propionic | 18.6 ± 0.63 c | 24.0 ± 0.01 b | 25.9 ± 0.16 a,b | 24.8 ± 0.32 a,b | 26.2 ± 0.23 a | 0.340 | <0.001 | <0.001 | <0.001 |
| Isobutyric | 5.0 ± 0.59 | 4.4 ± 0.67 | 4.6 ± 0.11 | 3.6 ± 0.11 | 3.5 ± 0.10 | 0.411 | 0.18 | 0.994 | 0.043 |
| Butyric | 18.6 ± 0.16 b,c | 19.9 ± 0.37 a,b | 18.3 ± 0.23 c | 20.0 ± 0.22 a | 18.6 ± 0.01 b,c | 0.231 | 0.009 | 0.370 | 0.014 |
| Isovaleric | 7.9 ± 0.15 a | 7.3 ± 0.17 a | 7.3 ± 0.17 a | 6.3 ± 0.13 b | 5.8 ± 0.00 b | 0.141 | <0.001 | 0.788 | <0.001 |
| Valeric | 2.5 ± 0.08 a,b | 3.3 ± 0.15 a | 2.9 ± 0.01 a,b | 3.1 ± 0.21 a,b | 2.6 ± 0.02 b | 0.120 | 0.042 | 0.842 | 0.415 |
| Acetic:propionic acid ratio | 2.5 ± 0.08 a | 1.7 ± 0.02 b | 1.5 ± 0.00 b | 1.6 ± 0.06 b | 1.6 ± 0.01 b | 0.049 | <0.001 | <0.001 | <0.001 |
CTL, control treatment; NA1, naringin (1.5 g/kg DMI); NA2, naringin (3.0 g/kg DMI); CHI1, chitosan (1.5 g/kg DMI); CHI2, chitosan, (3.0 g/kg DMI). 1 Standard error of pH is expressed in H ions. abc Different letters in the same row are statistically different; SEM, standard error of the difference among means; surface response: L: linear contrast; Q: quadratic contrast. VFA, volatile fatty acids.