Table 1.
Ingredient composition and nutrient levels of the experimental diets (% as fed)
| Items | Dietary L-lysine·H2SO4 levels (%) fed from d 1 to 21 | Dietary L-lysine·H2SO4 levels (%) fed from d 22 to 35 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 4 | 7 | 10 | 0 | 1 | 4 | 7 | 10 | |
| Ingredient, % | ||||||||||
| Corn | 59.12 | 59.75 | 62.41 | 65.21 | 68.85 | 60.67 | 61.27 | 63.67 | 67.77 | 71.58 |
| Soybean meal | 31.00 | 29.40 | 24.00 | 19.95 | 14.65 | 31.75 | 30.10 | 24.45 | 18.34 | 12.43 |
| Fish meal | 3.25 | 3.15 | 2.95 | 1.55 | 1.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
| Soybean meal | 3.00 | 2.97 | 2.80 | 2.00 | 1.00 | 4.00 | 4.00 | 3.95 | 2.70 | 1.70 |
| Limestone | 1.40 | 1.46 | 1.35 | 1.30 | 1.25 | 1.10 | 1.15 | 1.20 | 1.25 | 1.20 |
| Dicalcium phosphate | 1.10 | 1.12 | 1.20 | 1.50 | 1.60 | 1.40 | 1.40 | 1.52 | 1.55 | 1.55 |
| Salt | 0.30 | 0.30 | 0.30 | 0.30 | 0.30 | 0.30 | 0.30 | 0.30 | 0.30 | 0.30 |
| Mineral and vitamin premix1 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 | 0.50 |
| L-lysine·H2SO4 | 0.00 | 1.00 | 4.00 | 7.00 | 10.00 | 0.00 | 1.00 | 4.00 | 7.00 | 10.00 |
| DL-methionine | 0.15 | 0.16 | 0.20 | 0.25 | 0.28 | 0.10 | 0.10 | 0.15 | 0.20 | 0.21 |
| L-tryptophan | 0.00 | 0.00 | 0.00 | 0.04 | 0.07 | 0.00 | 0.00 | 0.00 | 0.02 | 0.06 |
| L-threonine | 0.00 | 0.01 | 0.11 | 0.22 | 0.32 | 0.00 | 0.00 | 0.08 | 0.19 | 0.29 |
| Choline chloride | 0.13 | 0.13 | 0.13 | 0.13 | 0.13 | 0.13 | 0.13 | 0.13 | 0.13 | 0.13 |
| Antioxidant | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 | 0.05 |
| Calculated nutritional value | ||||||||||
| ME, Mcal/kg | 3.04 | 3.05 | 3.10 | 3.10 | 3.10 | 3.10 | 3.11 | 3.16 | 3.15 | 3.16 |
| Analyzed nutritional value, %2 | ||||||||||
| Dry matter | 88.24 | 88.33 | 88.62 | 88.85 | 88.82 | 89.10 | 89.11 | 89.28 | 89.47 | 90.03 |
| Crude protein | 21.70 | 22.82 | 22.59 | 23.13 | 22.71 | 20.02 | 21.20 | 21.58 | 20.40 | 20.31 |
| Total calcium | 1.05 | 1.14 | 0.73 | 0.71 | 1.01 | 0.96 | 1.20 | 0.97 | 0.82 | 1.10 |
| Total phosphorus | 0.49 | 0.55 | 0.49 | 0.61 | 0.57 | 0.57 | 0.55 | 0.54 | 0.55 | 0.58 |
| Lysine | 1.30 | 1.89 | 3.18 | 4.19 | 5.78 | 1.25 | 1.69 | 3.57 | 4.61 | 6.47 |
| Tryptophan | 0.23 | 0.23 | 0.20 | 0.21 | 0.19 | 0.23 | 0.22 | 0.19 | 0.18 | 0.20 |
| Methionine | 0.49 | 0.49 | 0.49 | 0.48 | 0.43 | 0.36 | 0.38 | 0.42 | 0.42 | 0.39 |
| Cystine | 0.30 | 0.29 | 0.28 | 0.25 | 0.21 | 0.28 | 0.29 | 0.28 | 0.25 | 0.21 |
| Threonine | 0.81 | 0.80 | 0.83 | 0.83 | 0.80 | 0.78 | 0.75 | 0.73 | 0.75 | 0.77 |
1The mineral and vitamin premix provided the following per kg of feed: zinc, 75 mg; iron, 200 mg; copper, 15 mg; iodine, 0.88 mg; selenium, 0.35 mg; manganese, 100 mg; vitamin A, 9000 IU; vitamin D3, 3750 IU; vitamin E, 25 IU; vitamin K3, 2 mg; thiamine, 1.5 mg; vitamin B12, 120 μg; riboflavin, 6 mg; nicotinic acid, 40 mg; pantothenic acid, 10 mg; pyridoxine, 3 mg; biotin, 0.1 mg
2Values are the means of a chemical analysis conducted in duplicate, n = 6/diet