Based on forage grading index（GI2001）proposed by Prof. LU Dexun in 2001, this study selected new parameters and try to establish a new forage grading index (GI2008) for cows in 2008.To demonstrate the rationality of GI2008, we used GI2001, GI2008 and RFV to evaluate four forages quality and made a comparison of the results. The values of GI2001, GI2008 and RFV were calculated according to their formulas, respectively. The results showed that 1) the values of GI2008 for the 4 forages ranked as follows：alfalfa (145.50) > corn silage (108.44) > cheninsis (20.10) > corn stalk (12.09); the values of GI2001 ranked as follows: alfalfa (32.11)> corn silage (19.70) > cheninsis (9.39) >corn stalk (3.98); the values of RFV ranked as follows: alfalfa (109.2) > corn silage (100.12) > cheninsis (91.55) > corn stalk (69.93). The sequences of the four forages quality were identical by GI2008, GI2001 and RFV methods. GI2008 and GI2001 were superior to RFV, and both of them could give evaluating results for the forage quality more scientifically. The regression equation obtained between GI2001 and GI2008 as follows: Y=5.166 9X-12.683（R2=0.946 3，P<0.000 1，n=4）. GI2001 is simple and easy to operate, but GI2008 is more scientific than GI2001 when using for the field of research. Thus, GI2008 can more accurately and scientifically evaluate the quality of forages on research in future.［Chinese Journal of Animal Nutrition, 2011, 23（8）：1296 -1302］
HONG Min,GAO Min,LU Dexun,HU Honglian
. New Forage Grading Index: Its Establishment and Comparative Study on the Evaluation of Forage Quality with the Grading
Index-2001（GI2001）and Relative Feed Value (RFV)[J]. Chinese Journal of Animal Nutrition, 2011
, 23(08)
: 1296
-1302
.
DOI: 10.3969/j.issn.1006-267x.2011.08.007
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