Zhao Xiu-fang, Li Wei-jian, Huang Wei, Cao Zhe, Rong Yu-ping
Institute of Grassland Science, China Agricultural University, Beijing 100094, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2008 Sep;28(9):2094-7.
In the present paper, the analysis of the content of CP, NDF and ADF in the whole dry hay of oats was carried out by using near infrared reflectance spectroscopy (NIRS) technique, and in combination with the partial least square (PLS) regression algorithm the calibration analysis was performed at the same time. The results showed that the calibration models developed by the spectral data pretreatment of the second derivative + Norris smoothing, the multivariate scattering correction + second derivative + Norris smoothing, and the multivariate scattering correction were the best for CP, NDF and ADF with the same spectral regions (9668-4518, 9550-5543, 8943-4042 cm(-1)). All these models yielded coefficients of determination of calibration (r2 cal) for CP and NDF that are both higher than 0.95, and each error lower than 3%, approached the chemical analysis precision. Moreover, the values of (RPD) of CP and NDF were both higher than 3.0. The results of these studies indicate that the contents of CP and NDF can be used to measure various samples in screening and evaluating quality constituents of dry hay in oats. While the effect of ADF modelling was poorer, the coefficients of determination of calibration (r2 cal) and cross validation (r2 CV)for ADF were 0.9120, 0.8553 respectively. The root mean square error of calibration, root mean square error of cross validation, and root mean square error of prediction ( RMSEE, RMSECV and RMSEP) for ADF were 2.33%, 2.62% and 1.91% respectively, and the precision is near the precision of the chemical analysis. The models of ADF can be used to measure various samples in screening and evaluating quality constituents of dry hay of oats also. This study has proved that NIRS technique can be applied to detect the contents of CP, NDF and ADF in the whole dry hay of oats.
本文采用近红外反射光谱(NIRS)技术对燕麦全干牧草中粗蛋白(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的含量进行分析,并结合偏最小二乘(PLS)回归算法同时进行校准分析。结果表明,经二阶导数+Norris平滑、多元散射校正+二阶导数+Norris平滑以及多元散射校正等光谱数据预处理方法所建立的校准模型,在相同光谱区域(9668 - 4518、9550 - 5543、8943 - 4042 cm⁻¹)下,对CP、NDF和ADF的效果最佳。所有这些模型的校准决定系数(r² cal)对于CP和NDF均高于0.95,且各误差均低于3%,接近化学分析精度。此外,CP和NDF的剩余预测偏差(RPD)值均高于3.0。这些研究结果表明,CP和NDF的含量可用于燕麦干牧草质量成分筛选和评估中的各类样品测定。虽然ADF建模效果较差,但其校准决定系数(r² cal)和交叉验证决定系数(r² CV)分别为0.9120、0.8553。ADF的校准均方根误差、交叉验证均方根误差和预测均方根误差(RMSEE、RMSECV和RMSEP)分别为2.33%、2.62%和1.91%,其精度接近化学分析精度。ADF模型也可用于燕麦干牧草质量成分筛选和评估中的各类样品测定。本研究证明,NIRS技术可应用于检测燕麦全干牧草中CP、NDF和ADF的含量。