Table 1. Ingredients and nutritional composition of the two experimental diets (air-dried basis, %).
| Ingredients1 | HN diet | LN diet | Nutrient level3 | HN diet | LN diet |
|---|---|---|---|---|---|
| Corn | 58.20 | 57.20 | Digestible energy (MJ/kg) | 14.50 | 12.20 |
| Soybean meal | 11.00 | 0.00 | Crude protein | 13.10 | 11.00 |
| Wheat bran | 11.50 | 11.00 | Crude protein/digestible energy | 0.90 | 0.90 |
| Rice bran | 4.00 | 13.00 | Crude fiber | 4.56 | 6.86 |
| Alfalfa meal | 3.00 | 14.00 | Ether extract | 9.34 | 5.00 |
| Soybean oil | 7.50 | 0.00 | Ca | 0.62 | 0.58 |
| Dicalcium phosphate | 1.15 | 1.15 | Total P | 0.52 | 0.44 |
| Limestone | 0.79 | 0.79 | Available P | 0.28 | 0.26 |
| Salt | 0.30 | 0.30 | Lys | 1.11 | 0.83 |
| Premix2 | 1.00 | 1.00 | Met + Cys | 0.65 | 0.52 |
| Lys | 0.88 | 0.88 | |||
| Met | 0.27 | 0.27 | |||
| Thr | 0.33 | 0.33 | |||
| Tyr | 0.08 | 0.08 |
HN, higher-nutrient; LN, lower-nutrient.
1 All dietary components except for the alfalfa meal were provided by a feed manufacturer (Guilin city, China), and all components were mashed and pelletized. Alfalfa meal was purchased from Gansu Tianmu Co., Ltd. (Lanzhou city, China).
2 Premix provided the following per kg of feed: vitamin A, 12,040 IU; vitamin D3, 2,112 IU; vitamin E, 29.7 IU; vitamin K3, 2.8 mg; vitamin B1, 1.2 mg; vitamin B2, 7.1 mg; vitamin B6, 1.3 mg; vitamin B12, 0.03 mg; nicotinic acid, 42.9 mg; pantothenic acid, 21.6 mg; folic acid, 0.44 mg; biotin, 0.12 mg; choline, 320 mg; Fe, 80 mg; Cu, 40 mg; Zn, 140 mg; Mn, 52 mg; I, 0.56 mg; Co, 1.4 mg; and Se, 0.33 mg.
3 Digestible energy, crude protein, Ca, total phosphorus, and available phosphorus are calculated values, while other factors are shown as measured values.