Studies On The Establishement Of New Generation Of GI(GI₂₀₀₈) For The Application Of Mixed Foragesin The Dairy Cows Feeding

Based on forage grading index(GI)proposed by Prof.Dexun-Lu in 2002 ,This study was to select the new parameters to established new grading index(GI₂₀₀₈) and to develop the technigue for optimum mixed forage formulation by using GI₂₀₀₈,The results showed as follows.1.Evaluation of fiber and protein fractions in foragesAs far as the NDF fraction in forage was concerned , there had the relationship between animal ruminating behavior and NDF contents,therefore PeNDF regarded as reasonable choices to evaluate the technical index for NDF in forages.so for protein fraction,the fermentation of higher quality forage was higher than lower quality forage,so rumen degratable protein of high quality forage is higher that of low quality forage,which indicated DCP was a better index for evaluating protein fractation in forages.2.Comparasion of GI₂₀₀₈ and RFV,GI of forages quality The formula of new grading index(GI₂₀₀₈) is evaluation:GI₂₀₀₈=(NEL×DMI×DCP)/((1-pef)NDF),The order of using GI₂₀₀₈,GI and RFV was resulted in same evaluating order. The comparasion showed that using GI₂₀₀₈ was alfafa>silage corn>cheninsis>corn stalk.The results of the experiment showed that there was significantly correlationship between GI(X ,MJ) and it's GI₂₀₀₈(Y,MJ). The regression equation obtained were showed as follows: Y=5.1669X-12.683(R2=0.9463,P﹤0.0001,n=4)The results showed GI₂₀₀₈ and GI had the higher value than RFV,and both of them could gave evaluating result for the forage quality more scientifically, For feeding, GI indexs has simple and accurate charactristics,but GI₂₀₀₈ had more procise and scientific .According to the feed cost and the In Vitro degradation indexes of the mixed forages, one optimum formula of mixed forages in vitro bafch incubation was composed of silage corn: alfafa: corn stalk,their ratio was 50:20:30.Feeding trail by using GI₂₀₀₈ had technigue for mixed forage formula, With similer age,body weight,parity,milk production in mid-lactation dairy cows were slected and devided into 3 groups.ie,control GI₂₀₀₈ and GI groups.the cows were fed same concentrate with forage/concentrate ratio of 65:35,but different in mixed forages formula. Resualts were as follow : the GI₂₀₀₈ group had higher DMI value than the GI group and the control group. But there were no significant difference(Pï¹¥0.05). the GI₂₀₀₈ and the GI group also had higher3.5%FCM yield than the control group. In GI₂₀₀₈ group there was significant difference(P﹤0.05).in milk protein and milk fat percentage. the GI₂₀₀₈ and the GI groups also had an increasing tendency than the control group ,but no significant difference(P>0.05).the net income in GI₂₀₀₈ and GI groups were higher than the control group. the net income in GI₂₀₀₈ and GI groups respectively was 5.23$/d,4.53$/d.