Li Sen, He Liwen, Mo Fang, Zhang Wei
State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
Animals (Basel). 2023 Mar 6;13(5):947. doi: 10.3390/ani13050947.
Rumen degradation kinetics of 25 feedstuffs (six protein feeds, nine energy feeds and ten roughages) were first determined using the nylon bag technique in situ and the differences of degradation characteristics fitted with five or seven time points measuring data were evaluated with the goodness of fit (R) of degradation curves. Protein and energy feeds were incubated for 2, 4, 8, 16, 24, 36, 48 h, roughages were incubated for 4, 8, 16, 24, 36, 48, 72 h, where three and six data sets of five time points were screened out, respectively. Only the degradation parameters a (rapidly degraded proportion), b (slowly degraded proportion) and c (degradation rate of slowly degraded proportion) of several feeds at five time points were significantly different from those at seven time points ( < 0.05), and the others were not significant ( > 0.05). The R of the degradation curves obtained at five time points was closer to 1, indicating that the fitting obtained at five time points was more accurate in predicting the real-time rumen degradation rate of feed. These results indicate that it is feasible to determine the rumen degradation characteristics of feedstuffs by only setting five measuring time points.
首先采用尼龙袋原位技术测定了25种饲料（6种蛋白质饲料、9种能量饲料和10种粗饲料）的瘤胃降解动力学，并根据降解曲线的拟合优度（R）评估了拟合5个或7个时间点测量数据的降解特性差异。蛋白质和能量饲料培养2、4、8、16、24、36、48小时，粗饲料培养4、8、16、24、36、48、72小时，分别筛选出5个时间点的3组和6组数据集。仅几种饲料在5个时间点的降解参数a（快速降解比例）、b（缓慢降解比例）和c（缓慢降解比例的降解速率）与7个时间点的降解参数有显著差异（<0.05），其他差异不显著（>0.05）。5个时间点获得的降解曲线的R更接近1，表明5个时间点的拟合在预测饲料实时瘤胃降解率方面更准确。这些结果表明，仅设置5个测量时间点来测定饲料的瘤胃降解特性是可行的。
