本研究旨在观察细粉、中粉、未粉和粗粉豆粕（粒径分别为0.60-1.28、1.28-2.50、0.80-5.00和2.50-5.00 mm）干物质（DM）和粗蛋白质（CP）在绵羊瘤胃降解率和其日粮DM和CP的表观消化率，为反刍动物精料生产中豆粕适宜的粉碎粒度提供理论依据和技术参数。试验选用4只雄性体重相近装有瘤胃瘘管的成年东北细毛羊为试验动物，采用4×4拉丁方试验设计，尼龙袋和全收粪法测定4种粒度豆粕DM和CP的瘤胃降解率和表观消化率。结果表明，豆粕粉碎粒度越小，其DM和CP在绵羊瘤胃中的降解速度越快；细粉、中粉和未粉豆粕日粮DM（P>0.05）和CP（P<0.05）表观消化率均高于粗粉豆粕日粮，三者之间差异不显著（P>0.05）。豆粕粉碎过细在绵羊瘤胃中降解较多，未粉碎豆粕DM和CP在瘤胃降解率显著低于细粉和中粉豆粕（P<0.05或P<0.01），而日粮DM和CP消化率不受影响。结果提示，未粉豆粕可以直接饲喂牛、羊，既可提高豆粕DM和CP的利用效率，又能节省豆粕的粉碎费用。

To provide academic basis and technical parameters of fitting soybean meal (SBM) particle size crushed for feed processing of ruminant, four mature male Merino sheep with rumen cannula were used to measure the degradability of DM and CP of thin, mid, nature (not crush) and thick particles of SBM (particle diameters were 0.60-1.28, 1.28-2.50, 0.80-5.00 and 2.50-5.00 mm, respectively) in rumen and apparent digestibility of DM and CP of 4 particle SBM diets by nylon bag technique and total feces collection method using 4×4 Latin square design. The results revealed that rumen degradability of DM and CP of SBM increased with diminishing of particle size of SBM. The apparent digestibility of DM（P>0.05） and CP （P<0.05） of thick particle SBM diet was lower than those of thin, mid and nature particle SBM diets, but there were no significant differences among three treatments. Rumen degradability of DM and CP of not crushing SBM were significantly lower than those of thin and mid particle SBM. It was concluded that not crushing SBM was thought to be directly used in production of feed processing of ruminant due to its higher efficiency of DM and CP utilization, and expense saved for crushing in processing.