CAJ | 학술논문

为了预测不同粒度玉米在泌乳奶牛中瘤胃可降解干物质( RDDM)和瘤胃可降解淀粉( RDS)的含量,本试验选用5头带有永久性瘤胃瘘管的荷斯坦泌乳奶牛进行尼龙袋降解试验。玉米的粒度分别为300、450、600、2360和6000μm。降解试验采用“同时投入,分次取出”的方法,取样时间点分别为0、2、4、8、12、24、48 h。结果表明,与玉米粒度之间：除了0 h的淀粉降解率的相关性较差( R2=0.3113)外,其他各时间点的干物质和淀粉的降解率均表现出了较好的线性相关(干物质R2为0.6790~0.9334,淀粉R2为0.7467~0.9931,P<0.10)；干物质的快速降解部分( R2=0.8540)、慢速降解部分( R2=0.9010)和RDDM( R2=0.8799),淀粉的慢速降解部分( R2=0.8620)和RDS( R2=0.9290)均表现出了显著的线性相关( P<0.05)。本试验建立了通过粒度( x,μm)分布预测 RDDM ( y1,%)和 RDS 含量( y2,%)的回归公式：y1=67.96-0.00548x,R2=0.88,P=0.019；y2=70.12-0.00536x,R2=0.93,P=0.008。
위료예측불동립도옥미재비유내우중류위가강해간물질( RDDM)화류위가강해정분( RDS)적함량,본시험선용5두대유영구성류위루관적하사탄비유내우진행니룡대강해시험。옥미적립도분별위300、450、600、2360화6000μm。강해시험채용“동시투입,분차취출”적방법,취양시간점분별위0、2、4、8、12、24、48 h。결과표명,여옥미립도지간：제료0 h적정분강해솔적상관성교차( R2=0.3113)외,기타각시간점적간물질화정분적강해솔균표현출료교호적선성상관(간물질R2위0.6790~0.9334,정분R2위0.7467~0.9931,P<0.10)；간물질적쾌속강해부분( R2=0.8540)、만속강해부분( R2=0.9010)화RDDM( R2=0.8799),정분적만속강해부분( R2=0.8620)화RDS( R2=0.9290)균표현출료현저적선성상관( P<0.05)。본시험건립료통과립도( x,μm)분포예측 RDDM ( y1,%)화 RDS 함량( y2,%)적회귀공식：y1=67.96-0.00548x,R2=0.88,P=0.019；y2=70.12-0.00536x,R2=0.93,P=0.008。
This study using five lactating Holstein dairy cows with ruminal cannulas was conducted to predict ruminal degradable dry matter ( RDDM) and ruminal degradable starch ( RDS) contents of corn with different particle sizes. The particle sizes of corn were 300, 450, 600, 2 360 and 6 000 μm, respectively. The nylon bags were put in at the same time and took off fractionally in the degradation test, and the sampling time were 2, 4, 8, 12, 24 and 48 h, respectively. The results showed as follows:with particle size of corn, excepting a poor correlation of degradation rate of starch at 0 h ( R2=0.311 3) , liner correlations were found in degrada-tion rates of dry matter and starch at the other time points (R2 of dry matter was 0.679 0 to 0.933 4, R2 of starch was 0.746 7~0.993 1, P<0.10);significant liner correlations were found in rapidly ( R2=0.854 0) and slowly degraded parts of dry matter (R2=0.901 0) and RDDM (R2=0.879 9), as well as slowly degraded part of starch ( R2=0.901 0) and RDS ( R2=0.929 0) ( P<0.05) . Regression formulas of predicting the con-tents of RDDM ( y1 , %) and RDS ( y2 , %) of corn using particle size ( x, μm) distribution are established, which are as follows: y1=67.96-0.005 4 8x, R2=0.88, P=0.019; y2=70.12-0.005 36x, R2=0.93, P=0.008.