【摘要】 本试验选用12只体重30～35kg,安装有永久性瘤胃及十二指肠近端瘘管的内蒙古半细毛羯羊,研究不同处理、不同替换水平的玉米秸对日粮营养物质,特别是氮的消化和利用率的影响。试验结果表明,在日粮蛋白质水平相同的条件下,氨化处理组(AT组)和兴牧宝处理组(XT组)与未处理组(C组)相比,氮的消化率明显提高;且随着玉米秸替换水平的增加,粪、尿中的氮含量增加,氮沉积量减少,消化率下降,其中以日粮干草100%被玉米秸替换时差异极显著(P<0.01)。AT组和XT组与C组相比,DM、OM和ADF进食量均显著提高(P<0.05)。随着玉米秸替换比例的增加,不同处理组DM、OM和ADF消化率逐渐降低。60%替换水平的XT组和AX组DM、OM和ADF消化率均高于C组。玉米秸适宜的替换干草比例为30%～60%(占日粮干物质的21%～42%)。不同替换比例的玉米秸与日粮氮表观消化率之间存在相关关系,经斜率比法计算发现XT组与AT组对日粮氮的表观消化率差异不显著(P>0.05)。玉米秸的不同替换比例与日粮中DM的表观消化率存在相关关系,经斜率比法计算得知XT组日粮DM的表观消化率明显提高,与AT组相比差异显著(P<0.05)。更多还原

【Abstract】 Twelve wethers of 30～35kg Inner Mongolian semi-fine wool breed,fitted with permanent cannulas in the rumen and at the proximal duodenum and terminal ileum,were used to investigate the effects of different rates of substitution of treated corn stovers for hays in the diets on digestibilities and availabilities of nutrients,especially dietary nitrogen.The results showed that the digestibility of nitrogen were significantly increased in AT and XT groups compared with C group at same dietary protein level.Nitrogen excretions in feces and urine were increased,and deposition and digestibility of nitrogen were reduced with increasing the rates of substitution of corn stovers.The differences were significant(P<0.01)when hays were substituted by 100% corn stovers.AT and XT groups had greater intake of DM,OM,ADF than untreated groups(P<0.05).Digestibilities of DM,OM and ADF in treatment groups were reduced with increasing substitution rates.Compared with different treatments at 60% substitution rate,XT groups had greater digestibilities of DM,OM and ADF than AT and C groups.The appropriate substitution rate of corn stovers was 30%～60%(21%～42% DM).According to correlations between substitution rate and apparent dietary digestibility of nitrogen,the significantly differences of apparent digestibility of dietary nitrogen were found between XT and AT groups(P<0.05).According to correlations between substitition rate and apparent dietary digestibility,DM apparent digestibilities of XT group was markedly higher than that of AT group(P<0.05).更多还原