Table 1.
Chemical composition of total mixed diets (DM basis).
| Items 1 | Control | SRU | SRU-I | IBA-S | IBA |
|---|---|---|---|---|---|
| Ingredients, g/kg | |||||
| Corn | 270 | 270 | 270 | 270 | 270 |
| SBM | 150 | 91 | 102.5 | 113.5 | 125 |
| Wheat bran | 50 | 100 | 88.5 | 77.5 | 66 |
| SRU | 0 | 9 | 6 | 3 | 0 |
| IBA | 0 | 0 | 3 | 6 | 9 |
| NaCl | 10 | 10 | 10 | 10 | 10 |
| Sodium bicarbonate | 10 | 10 | 10 | 10 | 10 |
| Premix 2 | 10 | 10 | 10 | 10 | 10 |
| Whole corn silage | 300 | 300 | 300 | 300 | 300 |
| Wheat straw | 200 | 200 | 200 | 200 | 200 |
| Nutrient levels | |||||
| DM (g/kg) | 716 | 717 | 716 | 715 | 715 |
| OM (g/kg DM) | 937 | 938 | 938 | 936 | 936 |
| EE (g/kg DM) | 23.5 | 23.9 | 23.6 | 23.7 | 23.9 |
| CP (g/kg DM) | 131 | 131 | 131 | 131 | 131 |
| NDF (g/kg DM) | 365 | 379 | 376 | 372 | 370 |
| ADF (g/kg DM) | 204 | 211 | 210 | 209 | 207 |
1 SRU, 0.9% slow-release urea group; IBA, 0.9% isobutyramide group; SRU-I, 0.6% slow-release urea + 0.3% isobutyramide group; IBA-S, 0.6% isobutyramide + 0.3% slow-release urea group; SBM, soybean meal; DM, dry matter; OM, organic matter; EE, ether extract; CP, crude protein; NDF, neutral detergent fiber; ADF, acid detergent fiber. 2 Contained per kg premix: vitamin A, 60,000 IU; vitamin D3, 6000 IU; vitamin E, 400 UI; Fe, 500 mg; Cu, 200 mg; Zn, 500 mg; Mn, 400 mg; I, 5 mg; Se, 2 mg.