1 材料与方法
1.1 试验材料、时间与地点
1.2 试验设计
1.3 试验方法
1.3.1 试验材料处理
1.3.2 相关指标测定及计算
1.4 数据统计与分析
2 结果与分析
2.1 收获期与青贮对甜玉米秸秆营养物质含量的影响
表1 收获期与青贮对甜玉米秸秆营养物质含量的影响(干物质基础)Table 1 Effects of harvest time and silage on nutrient contents of SCS (DM basis) % |
| 项目 Items | 处理 Treatments | 收获期Harvest time | P值P-value | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| HT0 | HT1 | HT2 | HT3 | HT | S | HT×S | |||||
| 有机物 | 未青贮Un-silage | 90.51±0.24B | 91.07±0.31B | 90.57±0.27B | 90.81±0.87B | 0.060 | <0.001 | 0.069 | |||
| OM | 青贮Silage | 92.75±0.60A | 92.55±0.11A | 91.83±0.61A | 91.68±0.51A | ||||||
| 干物质 | 未青贮Un-silage | 20.58±2.42b | 22.47±1.97ab | 23.58±1.98a | 24.00±2.30a | 0.001 | 0.073 | 0.869 | |||
| DM | 青贮Silage | 19.33±1.39b | 20.77±0.79bc | 22.13±1.65ab | 23.70±0.93a | ||||||
| 粗脂肪 | 未青贮Un-silage | 1.79±0.10B | 2.32±0.27B | 1.78±0.12B | 2.13±0.59B | 0.053 | <0.001 | 0.788 | |||
| EE | 青贮Silage | 2.73±0.28A | 3.19±0.13A | 3.01±0.12A | 3.08±0.77A | ||||||
| 粗灰分 | 未青贮Un-silage | 7.25±0.60B | 7.45±0.11B | 8.17±0.61B | 8.32±0.51B | 0.092 | <0.001 | 0.068 | |||
| Ash | 青贮Silage | 9.49±0.24A | 8.93±0.31A | 9.43±0.27A | 9.19±0.87A | ||||||
| 钙 | 未青贮Un-silage | 0.33±0.02B | 0.31±0.01B | 0.34±0.06B | 0.34±0.03B | 0.053 | <0.001 | 0.438 | |||
| Ca | 青贮Silage | 0.41±0.02A | 0.41±0.01A | 0.48±0.02A | 0.46±0.08A | ||||||
| 磷 | 未青贮Un-silage | 0.31±0.06 | 0.31±0.04 | 0.32±0.04 | 0.32±0.02 | 0.964 | 0.652 | 0.990 | |||
| P | 青贮Silage | 0.32±0.06 | 0.33±0.06 | 0.31±0.02 | 0.33±0.04 | ||||||
同行数据肩标不同小写字母表示不同收获期间差异显著(P<0.05),同列数据肩标不同大写字母表示同一收获期青贮前后差异显著(P<0.05)。HT和S分别表示收获期和青贮。 | |
Values with different lowercase letter superscripts in the same row indicated significant difference between different harvest time (P<0.05), and values with difference capital letter superscripts in the same column indicated significant difference before and after silage of the same harvest time (P<0.05). HT and S represented harvest time and silage, respectively. The same as |
2.2 收获期与青贮对甜玉米秸秆碳水化合物含量和RFV的影响
表2 收获期与青贮对甜玉米秸秆碳水化合物含量及相对饲喂价值的影响(干物质基础)Table 2 Effects of harvest time and silage on carbohydrate content and RFV of SCS (DM basis) % |
| 项目 Items | 处理 Treatments | 收获期Harvest time | P值P-value | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| HT0 | HT1 | HT2 | HT3 | HT | S | HT×S | |||||
| 中性洗涤纤维 | 未青贮Un-silage | 53.77±1.00cA | 53.23±1.51cA | 56.10±1.28bA | 58.30±1.31aA | <0.001 | <0.001 | 0.041 | |||
| NDF | 青贮Silage | 48.00±1.30bB | 48.95±1.27bB | 48.20±1.06bB | 51.73±0.61aB | ||||||
| 酸性洗涤纤维 | 未青贮Un-silage | 32.35±0.87bA | 33.30±1.39abA | 35.00±1.82aA | 35.13±1.43aA | 0.001 | <0.001 | 0.582 | |||
| ADF | 青贮Silage | 28.80±1.47bB | 29.80±1.56bB | 30.55±1.84abB | 32.85±1.89aB | ||||||
| 酸性洗涤木质 | 未青贮Un-silage | 12.03±0.09b | 12.83±0.83ab | 12.96±0.17a | 13.27±0.62a | 0.001 | 0.530 | 0.638 | |||
| ADL | 青贮Silage | 12.28±0.27b | 12.48±0.74b | 13.26±1.03ab | 13.61±0.35a | ||||||
| 淀粉 | 未青贮Un-silage | 4.00±0.17A | 4.30±0.22A | 4.40±0.24A | 4.44±0.39A | 0.051 | <0.001 | 0.027 | |||
| Starch | 青贮Silage | 3.43±0.21B | 3.68±0.16B | 3.66±0.12B | 3.13±0.29B | ||||||
| 相对饲用价值 | 未青贮Un-silage | 153.82±2.83aB | 155.43±4.41aB | 147.45±3.40bB | 141.88±3.18cB | <0.001 | <0.001 | 0.061 | |||
| RFV | 青贮Silage | 172.36±4.58aA | 169.01±4.37aA | 171.61±3.78aA | 159.83±1.89bA | ||||||
2.3 收获期与青贮对甜玉米秸秆蛋白质组分的影响
表3 收获期与青贮对甜玉米秸秆蛋白质组分的影响(干物质基础)Table 3 Effects of harvest time and silage on protein components of SCS (DM basis) % |
| 项目 Items | 处理 Treatments | 收获期Harvest time | P值P-value | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| HT0 | HT1 | HT2 | HT3 | HT | S | HT×S | |||||
| 粗蛋白质 | 未青贮Un-silage | 11.50±0.51A | 11.80±0.41A | 11.90±0.90A | 12.23±0.21A | 0.121 | <0.001 | 0.140 | |||
| CP | 青贮Silage | 9.35±0.29B | 10.15±0.15B | 9.35±0.47B | 9.55±0.35B | ||||||
| 可溶性蛋白质 | 未青贮Un-silage | 8.30±0.22A | 8.10±0.24A | 7.53±0.62A | 7.77±0.37A | 0.104 | <0.001 | 0.067 | |||
| SP | 青贮Silage | 4.00±0.14B | 4.23±0.05B | 4.13±0.19B | 3.93±0.34B | ||||||
| 中性洗涤 不溶蛋白质 | 未青贮Un-silage | 1.65±0.04A | 1.67±0.06A | 1.70±0.03A | 1.71±0.08A | 0.043 | <0.001 | 0.675 | |||
| NDIP | 青贮Silage | 1.51±0.07bB | 1.57±0.04abB | 1.56±0.04abB | 1.61±0.03aB | ||||||
| 酸性洗涤 不溶蛋白质 | 未青贮Un-silage | 1.08±0.07 | 0.99±0.04 | 0.95±0.04 | 1.04±0.03 | 0.629 | 0.488 | 0.120 | |||
| ADIP | 青贮Silage | 0.97±0.09 | 0.98±0.08 | 1.03±0.12 | 1.01±0.06 | ||||||
2.4 收获期与青贮对甜玉米秸秆能量价值的影响
表4 收获期与青贮对甜玉米秸秆能量价值的影响(干物质基础)Table 4 Effects of harvest time and silage on energy value of SCS (DM basis) |
| 项目 Items | 处理 Treatments | 收获期Harvest time | P值P-value | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| HT0 | HT1 | HT2 | HT3 | HT | S | HT×S | |||||
| 总可消化养分 | 未青贮Un-silage | 49.13±0.36aB | 49.40±0.79aB | 47.01±0.45bB | 47.54±1.45bB | <0.001 | <0.001 | 0.651 | |||
| TDN/% | 青贮Silage | 54.20±0.66aA | 53.99±1.13aA | 52.63±1.51abA | 50.82±1.69bA | ||||||
| 代谢能 | 未青贮Un-silage | 7.44±0.05aB | 7.48±0.12aB | 7.11±0.07bB | 7.04±0.22bB | <0.001 | <0.001 | 0.651 | |||
| ME/(MJ/kg) | 青贮Silage | 8.20±0.10aA | 8.17±0.17aA | 7.97±0.23abA | 7.69±0.26bA | ||||||
| 维持净能 | 未青贮Un-silage | 6.14±0.10aB | 6.22±0.23aB | 5.55±0.12bB | 5.42±0.39bB | <0.001 | <0.001 | 0.624 | |||
| NEm/(MJ/kg) | 青贮Silage | 7.64±0.20aA | 7.58±0.35aA | 7.17±0.45abA | 6.63±0.49bA | ||||||
| 泌乳净能 | 未青贮Un-silage | 6.18±0.06aB | 6.11±0.10abB | 5.99±0.13bB | 5.98±0.10b | 0.001 | <0.001 | 0.582 | |||
| NEL/(MJ/kg) | 青贮Silage | 6.44±0.11aA | 6.37±0.11aA | 6.32±0.13abA | 6.15±0.14b | ||||||
| 增重净能 | 未青贮Un-silage | 1.64±0.05aB | 1.68±0.11aB | 1.34±0.06bB | 1.27±0.20bB | <0.001 | <0.001 | 0.657 | |||
| NEg/(MJ/kg) | 青贮Silage | 2.33±0.09aA | 2.30±0.15aA | 2.12±0.20abA | 1.87±0.23bA | ||||||
2.5 不同处理的甜玉米秸秆的主成分分析
表5 不同处理的甜玉米秸秆的主成分分析Table 5 Principal component analysis of SCS with different treatments |
| 项目 Items | 主成分Principal components | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 未青贮Un-silage | 青贮Silage | |||||||||
| 1 | 2 | 3 | 4 | 5 | 1 | 2 | 3 | 4 | ||
| 粗脂肪EE | 0.298 | -0.297 | -0.562 | -0.015 | -0.367 | 0.234 | 0.714 | 0.566 | 0.045 | |
| 钙Ca | -0.231 | -0.027 | 0.845 | -0.388 | -0.103 | -0.728 | -0.638 | 0.159 | 0.073 | |
| 磷P | -0.004 | -0.406 | 0.707 | 0.197 | 0.242 | -0.045 | 0.369 | -0.068 | 0.763 | |
| 中性洗涤纤维NDF | -0.582 | -0.618 | -0.047 | -0.048 | -0.401 | -0.553 | 0.543 | 0.224 | 0.381 | |
| 酸性洗涤纤维ADF | -0.258 | -0.912 | 0.056 | -0.042 | -0.091 | -0.919 | 0.068 | 0.191 | -0.094 | |
| 酸性洗涤木质素ADL | -0.822 | -0.070 | -0.136 | -0.278 | -0.005 | -0.884 | 0.100 | 0.035 | -0.029 | |
| 淀粉Starch | -0.369 | -0.032 | 0.099 | -0.885 | -0.055 | 0.323 | -0.808 | 0.000 | -0.082 | |
| 可溶性蛋白质SP | -0.019 | 0.154 | 0.107 | 0.036 | 0.923 | 0.003 | 0.006 | -0.856 | -0.276 | |
| 中性洗涤不溶蛋白质NDIP | -0.882 | -0.075 | -0.163 | 0.230 | 0.179 | -0.503 | 0.250 | 0.702 | -0.200 | |
| 酸性洗涤不溶蛋白质ADIP | 0.012 | 0.468 | 0.514 | 0.455 | -0.416 | -0.124 | -0.226 | 0.414 | 0.764 | |
| 总可消化养分TDN | 0.886 | 0.242 | -0.304 | 0.205 | 0.023 | 0.979 | -0.041 | 0.003 | -0.161 | |
| 代谢能ME | 0.886 | 0.242 | -0.304 | 0.205 | 0.023 | 0.979 | -0.041 | 0.003 | -0.161 | |
| 维持净能NEm | 0.887 | 0.242 | -0.300 | 0.203 | 0.028 | 0.978 | -0.050 | -0.001 | -0.166 | |
| 泌乳净能NEL | 0.258 | 0.912 | -0.056 | 0.042 | 0.091 | 0.919 | -0.068 | -0.191 | 0.094 | |
| 增重净能NEg | 0.885 | 0.242 | -0.306 | 0.205 | 0.021 | 0.980 | -0.036 | 0.005 | -0.159 | |
| 特征值Eigen value | 5.338 | 2.786 | 2.239 | 1.484 | 1.445 | 7.569 | 2.140 | 1.871 | 1.565 | |
| 贡献率Contribution rate/% | 35.588 | 18.574 | 14.928 | 9.895 | 9.631 | 50.457 | 14.269 | 12.470 | 10.433 | |
| 累积贡献率 Cumulative contribution rate/% | 35.588 | 54.163 | 69.091 | 78.986 | 88.617 | 50.457 | 64.727 | 77.197 | 87.631 | |
2.6 甜玉米秸秆青贮前后指标间的相关性分析
图1 甜玉米秸秆青贮前后指标间的相关性分析A:甜玉米秸秆青贮前指标间相关性分析;B:甜玉米秸秆青贮后指标间相关性分析。“*”为显著相关(P<0.05);“**”为极显著相关(P<0.01)。 Fig.1 Correlation analysis of indexes on SCS before and after silage A: correlation analysis of indexes of SCS before silage. B: correlation analysis of indexes of SCS after silage. “*” mean significant correlation (P<0.05); “**” mean extremely significant correlation (P<0.01). |
2.7 收获期对甜玉米秸秆饲用品质的综合评价
表6 不同处理甜玉米秸秆饲用品质隶属函数分析Table 6 Membership function analysis of forage quality of SCS with different treatments |
| 项目 Items | 收获期Harvest time | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| HT0 | HT1 | HT2 | HT3 | ||||||||||||||||||||
| 未青贮 Un-silage | 青贮 Silage | 未青贮 Un-silage | 青贮 Silage | 未青贮 Un-silage | 青贮 Silage | 未青贮 Un-silage | 青贮 Silage | ||||||||||||||||
| 有机物OM | 0.55 | 0.43 | 0.45 | 0.67 | 0.39 | 0.44 | 0.66 | 0.56 | |||||||||||||||
| 干物质DM | 0.55 | 0.52 | 0.47 | 0.44 | 0.46 | 0.54 | 0.54 | 0.62 | |||||||||||||||
| 粗脂肪EE | 0.65 | 0.67 | 0.45 | 0.37 | 0.43 | 0.46 | 0.43 | 0.51 | |||||||||||||||
| 粗灰分Ash | 0.55 | 0.43 | 0.46 | 0.67 | 0.39 | 0.44 | 0.66 | 0.56 | |||||||||||||||
| 钙Ca | 0.40 | 0.50 | 0.67 | 0.56 | 0.50 | 0.50 | 0.43 | 0.53 | |||||||||||||||
| 淀粉Starch | 0.51 | 0.54 | 0.40 | 0.52 | 0.40 | 0.44 | 0.50 | 0.45 | |||||||||||||||
| 中性洗涤纤维NDF | 0.34 | 0.60 | 0.50 | 0.50 | 0.36 | 0.50 | 0.53 | 0.51 | |||||||||||||||
| 酸性洗涤纤维ADF | 0.59 | 0.50 | 0.50 | 0.65 | 0.45 | 0.50 | 0.51 | 0.47 | |||||||||||||||
| 酸性洗涤木质素ADL | 0.58 | 0.66 | 0.58 | 0.39 | 0.41 | 0.39 | 0.44 | 0.60 | |||||||||||||||
| 可溶性蛋白质SP | 0.67 | 0.60 | 0.33 | 0.50 | 0.33 | 0.38 | 0.42 | 0.52 | |||||||||||||||
| 项目 Items | 收获期Harvest time | ||||||||||||||||||||||
| HT0 | HT1 | HT2 | HT3 | ||||||||||||||||||||
| 未青贮 Un-silage | 青贮 Silage | 未青贮 Un-silage | 青贮 Silage | 未青贮 Un-silage | 青贮 Silage | 未青贮 Un-silage | 青贮 Silage | ||||||||||||||||
| 中性洗涤不溶蛋白质NDIP | 0.52 | 0.53 | 0.38 | 0.44 | 0.67 | 0.48 | 0.44 | 0.38 | |||||||||||||||
| 总可消化养分TDN | 0.42 | 0.55 | 0.44 | 0.28 | 0.60 | 0.47 | 0.13 | 0.66 | |||||||||||||||
| 代谢能ME | 0.42 | 0.55 | 0.43 | 0.38 | 0.58 | 0.47 | 0.46 | 0.67 | |||||||||||||||
| 维持净能NEm | 0.42 | 0.55 | 0.44 | 0.37 | 0.60 | 0.47 | 0.45 | 0.66 | |||||||||||||||
| 增重净能NEg | 0.42 | 0.56 | 0.44 | 0.38 | 0.60 | 0.48 | 0.45 | 0.66 | |||||||||||||||
| 平均值Mean value | 0.51 | 0.55 | 0.46 | 0.47 | 0.48 | 0.46 | 0.47 | 0.56 | |||||||||||||||
