Table 1.
Ingredients and chemical composition of the experimental diets fed during dry and lactation periods.
| Dry Period | Lactation | |
|---|---|---|
| Ingredient, % DM | ||
| Corn silage | 22.94 | 48.22 |
| Soybean meal | 7.96 | 15.62 |
| Corn meal | - | 12.73 |
| Alfalfa hay | - | 9.63 |
| Barley silage | 35.32 | 7.44 |
| Crushed barley grain | - | 3.64 |
| Mineral supplement 1 | 0.48 | 1.90 |
| Hydrogenated vegetable fat | - | 0.83 |
| Wheat straw | 26.55 | - |
| Sunflower meal | 6.86 | - |
| Chemical composition 2 | ||
| DM, % | 44.84 | 50.42 |
| NEL Mcal/Kg of DM | 1.26 | 1.55 |
| Starch, % DM | 12.88 | 27 |
| Sugar, % DM | 1.56 | 2.43 |
| CP, % DM | 12.11 | 16.11 |
| MP, % DM | 8.29 | 10.90 |
| Ether extract, % DM | 2.59 | 3.34 |
| NDF, % DM | 52.90 | 34.04 |
| ADF, % DM | 32.44 | 19.79 |
| ADL, % DM | 6.97 | 2.97 |
| Ca, % DM | 0.31 | 0.72 |
| P, % DM | 0.34 | 0.43 |
| Mg, % DM | 0.22 | 0.24 |
| K, % DM | 0.94 | 1.04 |
| Na, % DM | 0.07 | 0.25 |
| DCAD, mEq/kg DM | 250 | - |
1 For dry cows, the supplement contained the following (in descending order): dicalcium phosphate, magnesium oxide, monocalcium phosphate, sodium chloride, and wheat middlings; vitamins—vitamin A 1,500,000 IU/kg, vitamin D3 150,000 IU/kg, and vitamin E 7000 mg/kg. The composition (on a DM basis) was as follows: 11.5% Ca, 8.6% P, 7.5% Mg, and 2.7% Na. For lactating cows, the supplement contained the following (in descending order): sodium bicarbonate, calcium carbonate, monocalcium phosphate, sodium tripolyphosphate, magnesium oxide, magnesium carbonate, sodium chloride, and barley meal; vitamins—vitamin A 900,000 IU/kg, vitamin D3 150,000 IU/kg, and vitamin E 3000 mg/kg. The composition (on a DM basis) was as follows: 11.8% Ca, 10.8% Na, 6.5% P, and 4.5% Mg. 2 Calculated according to NRC [14]; DM is dry matter, CP is crude protein, MP is metabolizable protein, NDF is neutral detergent fiber, ADF is acid detergent fiber, ADL is acid detergent lignin, and NEL is net energy for lactation.