甜菜粕替代玉米对奶牛生产性能及血液代谢的影响

试验旨在研究用甜菜粕替代玉米作为能量饲料对中国荷斯坦奶牛生产性能及血液代谢指标的影响。选择60头（泌乳日龄为61 d±21.6 d,产奶量为31.2 kg/d±6.2 kg/d）健康的泌乳前期荷斯坦奶牛，随机分为两棚，每棚3个处理，分别为对照组、20SBP组和40SBP组，每组10头牛。各组日粮除玉米和甜菜粕外，其它成分相同。试验结果表明，各个处理间的干物质采食量、产奶量和能量校正乳都差异不显著（P>0.05）。乳蛋白和乳脂等乳成分的产量和百分含量都不受甜菜粕替代玉米比例的影响（P>0.05），随着甜菜粕饲喂比例的增加，其含量有升高的趋势。血尿氮和葡萄糖浓度显著降低（P<0.01）。各个处理间的非脂化脂肪酸（NEFA）、β-羟丁酸（BHBA）等其他血液生化指标的浓度无显著变化（P>0.05）。因此，在奶牛日粮中用甜菜粕替代玉米作为能量来源,基本不会影响奶牛的生产性能及血液代谢情况，同时降低了奶牛的饲养成本。

Effects of Sugar Beet Pulp Substituted for Ground Corn on the Performance and Blood Metabolite of Dairy Cows

The objective of this study was to evaluate the effect of sugar beet pulp （SBP） substituted for ground corn on the performance and nutritional status as measured using blood metabolites as an energy source feed-stuff for Chinese Holstein lactating dairy cows. Sixty multifarious Holstein cows（61±21.6 DIM, 31.2 kg/d±6.2 kg/d） were randomly divided into two pens and within each pen where three groups （control,20SBP or 40SBP） and each group comprised of 10 cows （n=10）.Besides SBP and corn, The remainder of the ration was the same for all groups. The results showed that dry matter intake, milk production，energy corrected milk （ECM） were not effected by increasing SBP substitution（P>0.05）. The content and yields of milk protein, milk fat, milk lactose, total solids （TS） and solid non-fat （SNF） were unaffected by substituting SBP for ground corn （P>0.05）.As the SBP level increased, the content of milk composition was a rising tendency. In blood metabolite, the concentrations of blood urea nitrogen （BUN） and serum glucose decreased when SBP was added（P<0.01）.No significant difference in NEFA,BHBA, TG,LDLD,HDLD,TP,ALB,GLB,CHOL of the blood among the treatment groups in this experiment was detected. The results indicated that the performance and blood metabolite were unaffected by substituting SBP for ground corn， sugar beet pulp was equal to corn as an energy source, and decreased the cost.