Table 2.
Ingredient and chemical composition, and nutritional values of experimental diets fed to dairy cows (g/kg of DM); mean ± (SD).
| Item 1 | Diet 2 | |||
|---|---|---|---|---|
| GS | GSO | GSMS | GSMSO | |
| Ingredient composition (n = 20) | ||||
| Grass silage | 560 (13.1) | 530 (13.7) | 276 (11.5) | 283 (11.9) |
| Maize silage | 0 | 0 | 290 (8.5) | 258 (6.7) |
| Crimped barley | 330 (10.3) | 318 (9.3) | 328 (5.9) | 314 (5.20) |
| Rapeseed meal | 90 (2.8) | 90 (2.7) | 90 (1.6) | 90 (1.3) |
| Rapeseed oil | 0 | 42 (4.2) | 0 | 39 (2.8) |
| Mineral mixture | 20 (0.46) | 20 (0.45) | 16 (0.27) | 16 (0.24) |
| Chemical composition (n = 4) | ||||
| Organic matter | 922 (3.3) | 924 (2.9) | 935 (2.1) | 935 (1.6) |
| Crude protein | 160 (9.0) | 154 (3.1) | 138 (9.3) | 133 (4.5) |
| Neutral detergent fibre (NDF) | 371 (10.3) | 355 (5.4) | 348 (14.4) | 332 (9.7) |
| Indigestible NDF (iNDF) | 61.9 (3.8) | 59.4 (2.0) | 68.8 (3.8) | 66.1 (2.2) |
| pdNDF | 309 (10) | 296 (8.7) | 279 (9.1) | 266 (6.7) |
| Crude fat | 35.1 (0.57) | 75.3 (4.1) | 34.6 (0.78) | 72.9 (2.6) |
| Nutritional values (n = 4) | ||||
| ME, MJ/kg of DM | 11.9 (0.04) | 12.8 (0.08) | 11.8 (0.03) | 12.6 (0.05) |
| MP, g/kg of DM | 92.5 (0.49) | 88.7 (0.71) | 92.0 (0.35) | 88.6 (0.41) |
| PVB, g/kg of DM | 26.9 (0.30) | 26.4 (0.41) | 5.9 (0.98) | 6.1 (0.65) |
1 Rapeseed meal is ExPro-00SF (AAK Sweden AB, Karlshamn, Sweden); Mineral mixture—Mixa Optimal (Lantmännen Lantbruk AB, Malmö, Sweden); pdNDF—potentially digestible NDF (NDF-iNDF); ME—metabolisable energy and PVB—protein balance in the rumen, both calculated based on coefficients from feed tables [20]; MP—metabolisable protein calculated according to Spörndly [21]; 2 GS—grass silage; GSO—grass silage with rapeseed oil supplementation; GSMS—grass silage plus maize silage; GSMSO—grass silage plus maize silage with rapeseed oil supplementation.