Nutritional and Economic Implications of Protein Variance and Application of Statistical Process Control in the Chinese Feed Industry     

Zhichun Yan  Timothy J. Herrman  Thomas Loughin  Allen M. Featherstone  Dingyaun Feng 《Cereal Chemistry》2003,80(5):623-626

The adoption of Statistical Process Control (SPC) in the Chinese feed industry to reduce finished feed protein and moisture content variation can improve feed quality and profitability. Two studies were conducted to characterize protein variation in the Chinese feed industry. Study I involved four participating feed mills where we collected three samples per bag from four bags per lot of soybean meal, rapeseed meal, fish meal, corn gluten meal, meat & bone meal, and cottonseed meal. We analyzed these ingredients for protein and moisture content. Cottonseed meal and meat & bone meal displayed the highest protein variability between bags and within bags compared with other protein ingredients. We found no significant difference for within‐bag protein variance of the other feed ingredients; however, soybean meal had a significantly lower between‐bag variance (0.04%). Study II assessed the effect of adopting SPC. Five feed mills provided data for one year of finished feed protein and moisture content before and after adopting SPC. Three of the five feed mills experienced a significant (P < 0.10) reduction (0.20, 0.52, and 0.70%) in the absolute finished feed protein variation after adopting SPC. The two feed mills that did not display a significant reduction in absolute protein variation were already manufacturing feed with a low (<0.4% protein) absolute deviation from the target. These data demonstrate that feed mill managers can control finished feed variability through a number of management techniques including SPC.  相似文献   

气候变化对大兴安岭西麓林牧交错带木本植物物候期的影响   总被引：1，自引：0，他引：1  

王彦平  金磊  高健  王志春 《中国农学通报》2022,38(20):29-37

为了揭示气候变化背景下林牧交错带木本植物物候期的变化趋势及对气候变化的响应,为林草交错带固沙防风等生态恢复工程提供科学气象参考依据,利用内蒙古呼伦贝尔市鄂温克牧业气象试验站1994—2019年观测的榆树、小叶杨和紫丁香3种木本植物物候观测资料及同期气象数据,采用线性倾向估计、Pearson 相关系数、散点图等方法,分析了近26 年气候变化对大兴安岭西麓林牧交错带木本植物物候期的影响。结果表明：近26 年,大兴安岭西麓植物生长季气温显著升高,降水变化趋势不明显。榆树、小叶杨和紫丁香3种木本植物花芽开放期提前,落叶末期推后,且落叶末期推迟天数较多,平均每10 年分别推迟9.6、7.5 和8.5天。生长季显著延长,平均生长季分别为160~164天。气温是影响榆树、小叶杨和紫丁香春季花芽开放期和秋季落叶末期的关键气象因子。3种木本植物春季花芽开放期的提前对温度上升的响应是显著负相关关系,落叶末期推后对温度上升的响应显著正正相关关系。说明气候变暖背景下,3种木本植物花芽开放期提前,落叶末期推迟,生长期长度增加;且推迟天数较花芽开放期提前天数更大,说明气候变化对木本植物落叶末期影响更明显,落叶末期对生长季长度增加的贡献更大;大兴安岭西麓林牧交错带木本植物物候期的变化主要是受气温的影响,与降水量关系不大。  相似文献