粗饲料品质评定指数新一代分级指数的建立及与分级指数（GI_（2001））和饲料相对值（RFV）的比较研究

摘要

试验的目的是在卢德勋2001年提出的粗饲料分级指数（GI2001）的基础上筛选一些新指标在奶牛粗饲料中建立新一代分级指数（gradingindex2008,GI2008）,并用GI2008、GI2001和饲料相对值（RFV）对4种粗饲料品质进行分级比较。根据公式分别计算4种粗饲料的GI2008、GI2001和RFV值。结果表明,4种粗饲料（苜蓿干草、玉米青贮饲料、羊草、玉米秸秆）的GI2008值分别为145.50、108.44、20.10和12.09MJ/d;GI2001值分别为32.11、19.70、9.39和3.98MJ/d;RFV值分别为109.20、100.12、91.55和69.93MJ/d。三者对粗饲料品质划分次序一致。GI2008和GI2001对粗饲料品质分级均优于RFV,二者比较,GI2008与GI2001均能科学地对粗饲料品质进行评定,GI2001值（X,MJ）与GI2008值（Y,MJ）存在如下回归关系：Y=5.1669X-12.683（R2=0.9463,P〈0.0001,n=4）。结果提示,在实际应用中,GI2001指标简便易行,而GI2008主要用于研究目的,科学性比较强。在今后的研究中使用GI2008能更准确而科学地对粗饲料品质进行分级划分。%Based on forage grading index（GI2001）proposed by Prof.LU De-xun in 2001,in this study we selected new parameters and attempted to establish a new forage grading index（GI2008）for cows in 2008.In order to confirm the rationality of GI2008,GI2001 and RFV were used to evaluate four forages quality and the results were compared.The values of GI2001,GI2008 and RFV were calculated according to their formulas,respectively.The results showed that the values of GI2008 for the 4 forages ranked as follows：alfalfa（145.50）corn silage（108.44）chinensis（20.10）corn stalk（12.09）;the values of GI2001 ranked as follows：alfalfa（32.11）corn silage（19.70）chinensis（9.39）corn stalk（3.98）;the values of RFV ranked as follows：alfalfa（109.20）corn silage（100.12）chinensis（91.55）corn stalk（69.93）.The sequences of the quality of four forages were identical by GI2008,GI2001 and RFV methods.GI2008 and GI2001 were superior to RFV,and both of them could be used to evaluate the forage quality scientifically.The regression equation obtained between GI2001 and GI2008 was as follows：Y=5.1669X-12.683（R2=0.946 3,P0.000 1,n=4）.GI2001 is simple and easy to operate,but GI2008 is more scientific than GI2001 when using for research purpose.Thus,GI2008 can more accurately and scientifically evaluate the quality of forages on research in future.