Measurement and evaluation of grading indexes (GI) of five forages

The study was made by calculating the Grading Index (GI) of five kinds of forage grasses with their neutral washing fiber (NDF), acid washing fiber (ADF) and acid washing lignin (ADL) as different cellulose index to determine the conventional nutrient components , the in vitro digestion rate, gross energy, and dry matter intake. Comparing and analyzing GI calculation, the results showed that the grading index calculated by ADL as cellulose index was more reasonable, and also conformed to the actual feeding conditions. And the preferential order was alfalfaerect milkvetchryegrasssorghum Hybrid sudan grassChinese pennisetum.