1 材料与方法
1.1 试验设计
1.2 试验饲粮
表1 基础饲粮组成及营养水平(风干基础)Table 1 Composition and nutrient levels of the basal diet (air-dry basis) |
| 项目Items | 含量Content | ||
|---|---|---|---|
| 原料Ingredients | |||
| 玉米Corn | 56.62 | ||
| 豆粕Soybean meal | 23.40 | ||
| 豆油Soybean oil | 2.50 | ||
| 小麦麸Wheat bran | 4.00 | ||
| 菊花梗粉Chrysanthemum stalks powder | 4.90 | ||
| 石粉Limestone | 5.80 | ||
| 磷酸氢钙CaHPO4 | 1.70 | ||
| DL-蛋氨酸DL-methionine | 0.10 | ||
| 维生素预混料Vitamin premix1) | 0.10 | ||
| 微量元素预混料Trace element premix1) | 0.20 | ||
| 食盐NaCl | 0.40 | ||
| 沸石粉Zeolite powder | 0.28 | ||
| 合计Total | 100.00 | ||
| 营养水平Nutrient levels2) | |||
| 代谢能ME/(MJ/kg) | 11.31 | ||
| 粗纤维CF | 4.58 | ||
| 粗蛋白质CP | 16.27 | ||
| 钙Ca | 2.97 | ||
| 总磷TP | 0.75 | ||
| 蛋氨酸Met | 0.35 | ||
| 赖氨酸Lys | 0.89 | ||
| 蛋氨酸+半胱氨酸Met+Cys | 0.63 | ||
| 苏氨酸Thr | 0.61 | ||
| 色氨酸Trp | 0.22 |
1)维生素预混料和微量元素预混料为每千克饲粮提供 The vitamin premix and trace element premix provided the following per kilogram of the diet: VA 9 000 IU,VD3 2 000 IU,VE 40 mg,VK1 2 mg,VB2 4.0 mg,VB6 4.0 mg,烟酰胺 nicotinic acid 30 mg,叶酸 folic acid 0.5 mg,VB12 12 μg,泛酸钙 calcium pantothenate 11 mg,生物素 biotin 0.2 mg,Se 0.5 mg,Fe 80 mg,Mn 30 mg,Cu 4 mg,I 0.3 mg,Zn 0.3 mg。 2)粗蛋白质、粗纤维和苏氨酸为实测值,其他营养水平为计算值。CP, CF and Thr were measured values, while the other nutrient levels were calculated values. |
1.3 饲养管理
1.4 采集样品与指标测定
1.4.1 营养成分测定
1.4.2 生产性能
1.4.3 血浆生殖激素、抗氧化和生化指标
1.5 统计分析
2 结果
2.1 饲粮苏氨酸水平对产蛋期种鹅生产性能的影响
表2 饲粮苏氨酸水平对产蛋期种鹅生产性能的影响Table 2 Effects of dietary threonine level on performance of breeding geese during laying period |
| 项目 Items | 饲粮苏氨酸水平Dietary threonine levels/% | SEM | P值 P-value | ||||
|---|---|---|---|---|---|---|---|
| 0.61 | 0.68 | 0.75 | 0.82 | 0.89 | |||
| 产蛋率Laying rate/% | 42.26 | 48.95 | 44.17 | 43.39 | 41.82 | 0.898 | 0.071 |
| 平均日采食量 Average daily feed intake/(g/d) | 207.84a | 208.33a | 205.00ab | 204.81ab | 199.59b | 1.051 | 0.049 |
| 平均蛋重Average egg weight/g | 115.92 | 116.21 | 116.69 | 116.71 | 116.03 | 0.573 | 0.990 |
| 料蛋比Feed to egg | 4.26a | 3.69b | 4.00ab | 4.07ab | 4.14a | 0.064 | 0.050 |
| 产蛋数Egg number/(个/只) | 41.41 | 47.98 | 43.29 | 42.53 | 40.99 | 0.880 | 0.071 |
| 产蛋总重Egg mass/(kg/只) | 4.79 | 5.56 | 5.05 | 4.96 | 4.76 | 0.098 | 0.054 |
| 种蛋受精率 Fertilization rate of breeding eggs/% | 85.00 | 90.00 | 90.00 | 88.33 | 88.33 | 0.970 | 0.914 |
| 受精蛋孵化率 Hatching rate of breeding eggs/% | 90.17 | 92.73 | 90.70 | 90.46 | 90.83 | 0.930 | 0.920 |
同行数据肩标不同小写字母表示差异显著(P≤0.05),相同或无字母表示差异不显著(P>0.05)。下表同。 | |
In the same row, values with different small letter superscripts mean significant difference (P≤0.05), while with the same or no letter superscripts mean no significant difference (P>0.05). The same as below. |
2.2 饲粮苏氨酸水平对产蛋期种鹅血浆生殖激素指标的影响
表3 饲粮苏氨酸水平对产蛋期种鹅血浆生殖激素指标的影响Table 3 Effects of dietary threonine levels on plasma reproductive hormone indices of breeding geese during laying period |
| 项目 Items | 饲粮苏氨酸水平Dietary threonine levels/% | SEM | P值 P-value | ||||
|---|---|---|---|---|---|---|---|
| 0.61 | 0.68 | 0.75 | 0.82 | 0.89 | |||
| 促黄体素LH/(mIU/mL) | 11.47 | 11.82 | 11.88 | 12.02 | 11.49 | 0.199 | 0.899 |
| 催乳素PRL/(mIU/L) | 659.71 | 596.29 | 605.72 | 605.91 | 611.86 | 9.793 | 0.269 |
| 雌二醇E2/(pg/mL) | 338.14 | 356.32 | 342.55 | 339.70 | 333.44 | 4.120 | 0.505 |
| 促卵泡素FSH/(mIU/mL) | 5.48b | 5.87a | 5.70ab | 5.66ab | 5.61ab | 0.043 | 0.047 |
| 孕酮PROG/(ng/mL) | 7.53 | 7.56 | 7.60 | 7.80 | 7.72 | 0.053 | 0.489 |
2.3 饲粮苏氨酸水平对产蛋期种鹅血浆抗氧化指标的影响
表4 饲粮苏氨酸水平对产蛋期种鹅血浆抗氧化指标的影响Table 4 Effects of dietary threonine levels on plasma antioxidant indices of breeding geese during laying period |
| 项目 Items | 饲粮苏氨酸水平Dietary threonine levels/% | SEM | P值 P-value | ||||
|---|---|---|---|---|---|---|---|
| 0.61 | 0.68 | 0.75 | 0.82 | 0.89 | |||
| 总抗氧化能力T-AOC/(U/mL) | 8.94 | 9.44 | 9.29 | 9.23 | 9.22 | 0.213 | 0.974 |
| 丙二醛MDA/(nmol/mL) | 3.37a | 3.05b | 3.18ab | 3.28a | 3.29a | 0.036 | 0.032 |
| 谷胱甘肽过氧化物酶 GSH-Px/(U/mL) | 277.24 | 317.71 | 303.40 | 273.64 | 279.46 | 8.072 | 0.351 |
| 谷胱甘肽GSH/(μmol/mL) | 14.63 | 13.52 | 15.10 | 15.48 | 14.33 | 0.611 | 0.891 |
| 过氧化氢酶CAT/(U/mL) | 0.95 | 1.05 | 0.82 | 0.98 | 0.84 | 0.084 | 0.904 |
| 超氧化物歧化酶SOD/(U/mL) | 253.64 | 299.97 | 270.48 | 254.03 | 254.64 | 7.470 | 0.222 |
2.4 饲粮苏氨酸水平对产蛋期种鹅血浆生化指标的影响
表5 饲粮苏氨酸水平对产蛋期种鹅血浆生化指标的影响Table 5 Effects of dietary threonine levels on plasma biochemical indices of breeding geese during laying period |
| 项目 Items | 饲粮苏氨酸水平Dietary threonine levels/% | SEM | P值 P-value | ||||
|---|---|---|---|---|---|---|---|
| 0.61 | 0.68 | 0.75 | 0.82 | 0.89 | |||
| 尿素氮UN/(mmol/L) | 2.31ab | 1.78bc | 1.99bc | 2.17abc | 2.57a | 0.084 | 0.018 |
| 甘油三酯TG/(mmol/L) | 1.21 | 1.67 | 1.65 | 0.88 | 2.88 | 0.354 | 0.479 |
| 尿酸UA/(mmol/L) | 0.71 | 0.71 | 0.96 | 0.67 | 0.89 | 0.078 | 0.740 |
| 总蛋白TP/(g/L) | 54.73 | 50.14 | 52.26 | 47.56 | 47.09 | 1.910 | 0.721 |
| 葡萄糖GLU/(mmol/L) | 13.98 | 14.81 | 11.73 | 12.76 | 13.23 | 0.553 | 0.493 |
| 白蛋白ALB/(g/L) | 15.58 | 14.44 | 16.36 | 14.24 | 14.51 | 0.610 | 0.806 |
| 总胆固醇TCHO/(mmol/L) | 4.44 | 4.07 | 4.06 | 4.54 | 3.77 | 0.198 | 0.779 |
| 高密度脂蛋白胆固醇 HDL-C/(mmol/L) | 2.19 | 2.72 | 2.72 | 3.80 | 2.46 | 0.207 | 0.128 |
| 低密度脂蛋白胆固醇 LDL-C/(mmol/L) | 2.02b | 2.68ab | 2.42ab | 3.50a | 1.73b | 0.203 | 0.044 |
| 碱性磷酸酶AKP/(金氏单位/dL) | 0.58 | 0.56 | 0.66 | 0.68 | 0.65 | 0.041 | 0.893 |
| 天门冬氨酸氨基转移酶AST/(U/L) | 21.82ab | 26.30a | 23.07a | 22.53ab | 16.66b | 1.018 | 0.035 |
| 丙氨酸氨基转移酶ALT/(U/L) | 14.76 | 12.70 | 10.27 | 7.36 | 12.45 | 1.254 | 0.427 |
2.5 苏氨酸适宜水平线性回归分析
表6 产蛋期种鹅饲粮中适宜苏氨酸水平Table 6 Dietary optimal threonine level for breeding geese during laying period |
| 项目 Item | 回归方程 Regression equation | 决定系数 R2 | 适宜苏氨酸水平 Optimal threonine level/% | P值 P-value |
|---|---|---|---|---|
| 平均日采食量Average daily feed intake/(g/d) | y=226.564-28.600x | 0.828 | 0.68 | 0.032 |
