Table 2.
Gas production and fermentation parameters of cabbages (n = 3) and barley, sugar beet pulp, and wheat DDGS (dried distiller grains with solubles) used as reference (n = 1).
| Item | Cabbages | SEM 3 | p | Reference Feeds | |||||
|---|---|---|---|---|---|---|---|---|---|
| Brussels Sprouts | White Cabbage | Savoy Cabbage | Red Cabbage | Barley | Sugar Beet Pulp | Wheat DDGS | |||
| Gas production parameters 1 | |||||||||
| A (mL/g) | 275 c | 219 a | 229 ab | 233 b | 3.27 | <0.001 | 352 | 329 | 185 |
| c (%/h) | 5.55 c | 4.51 b | 4.75 b | 3.71 a | 0.17 | <0.001 | 5 | 5.21 | 4.15 |
| Lag (h) | 2.59 | 2.44 | 3.03 | 2.73 | 0.187 | 0.169 | 2.85 | 3.83 | 0 |
| AGPR (mL/h) | 9.11 c | 6.17 ab | 6.49 b | 5.47 a | 0.239 | <0.001 | 10.5 | 9.52 | 5.55 |
| DMED (%) | 58.4 b | 51.7 a | 49.1 a | 50.4 a | 0.69 | <0.001 | 45 | 45.2 | 38.4 |
| Fermentation parameters 2 | |||||||||
| Gas (mL) | 39.5 c | 34.2 a | 35 a | 36.8 b | 0.51 | <0.001 | 49.9 | 43.9 | 26.3 |
| pH | 6.52 a | 6.61 bc | 6.65 c | 6.60 b | 0.011 | <0.001 | 6.60 | 6.56 | 6.73 |
| Total volatile fatty acids (VFA; µmol) |
1632 | 1636 | 1612 | 1673 | 19.6 | 0.186 | 1452 | 1700 | 1311 |
| Individual VFA (mol/100 mol) | |||||||||
| Acetate (Ac) | 57.5 a | 62.6 b | 62.5 b | 62.9 b | 0.25 | <0.001 | 56.6 | 65.5 | 53.4 |
| Propionate (Pr) | 28.2 b | 24.5 a | 24.3 a | 24.1 a | 0.25 | <0.001 | 22.2 | 25.2 | 33.3 |
| Butyrate | 9.06 b | 8.18 a | 8.04 a | 8.31 a | 0.104 | <0.001 | 17.5 | 6.93 | 6.34 |
| Minor VFA | 5.23 b | 4.73 a | 5.15 b | 4.65 a | 0.106 | <0.001 | 3.70 | 2.31 | 6.96 |
| Ac/Pr (mol/mol) | 2.04 a | 2.55 b | 2.57 b | 2.60 b | 0.031 | <0.001 | 2.55 | 2.60 | 1.61 |
| NH3-N (mg/L) | 288 c | 223 a | 257 b | 218 a | 5.4 | <0.001 | 156 | 86.8 | 223 |
a, b, c Within cabbages, means in the same row with different superscript differ (p < 0.05). 1 A: potential gas production; c: fractional rate of gas production; Lag: is the time needed to start gas production; AGPR: average gas production rate; DMED: dry matter effective degradability estimated for a rumen digesta passage of 0.042 per h; 2 Determined in 24-h incubations in batch cultures of ruminal microorganisms containing 200 mg of substrate dry matter; VFA: volatile fatty acids; Minor VFA: calculated as the sum of isobutyrate, isovalerate, and valerate; 3 SEM: standard error of the mean.