The Study On Lignocellulose Of 7 Kinds Of Forage At Different Growth Stages And Evaluation Of Feeding

In order to clarify the lignocellulose content of different growth seasons of main cultivated forage in Shanxi and their feeding value.This experiment uses winter wheat(XM),rye(HM),and small rye(XHM);spring sow(Yo M),early maturing oats(LX),late-maturing oats(YW),and alfalfa(MX).The subjects were tested for cellulose content,hemicellulose content,lignin content,fresh grass yield,hay yield,and various nutrient specifications.The Cornell Net Carbohydrate-Protein System(CNCPS)was used to calculate carbohydrate and protein content,and the Milk Yield Evaluation System of Alfalfa/Grass(Milk 2016)of University of Wisconsin was used to evaluate the quality of forage.The results showed that the yield and nutrient composition of 7 kinds of forage were affected by different growth stages.With the passage of growth period,the fresh grass yield and hay yield of per forage showed a trend of gradual accumulation.The change of hay yield and fresh grass yield was basically the same.The fresh grass yield first increased and then decreased to different degrees,and the maximum value was in the flowering period.Although the fresh grass yield in the flowering period was high,the fresh to dry ratio was significantly lower than that in the filling period.Compared with the utilization rate of forage grass,the filling period was more suitable for cutting.From the nutritional composition of the 7 kinds of forages,the nutritional content of the forages in different growth stages was significantly different.With the passage of growth period,the contents of crude protein CP and crude fat EE increased from jointing stage to heading stage,but decreased gradually from heading stage to maturity stage.The content of ADL in pickling lignin increased with the growth period.The yield of YW was significantly higher than that of other forages,and it was best to mow at the filling stage.Changes of lignocellulosic composition of forage grass in different growth stages.The hemicellulose and lignin in the seven forages showed a gradual increase with the growth period,while the cellulose content of different varieties did not show a significant trend with the growth period,so different feeding The lignocellulose content of grass was different.The highest contentof lignocellulose in XM and LX was 63.93% and 64.12% in the filling stage.The highest content of HM,YW and Yo M and lignocellulose were in the ripening period,respectively.69.86%,69.21% and 63.25%;the content of lignocellulose in the jointing stage of XHM was 81.22% at the heading stage;the highest content of lignocellulose in MX was 66.57% in the pod-forming period.In addition,according to the results of this test,the forage lignin determined by the acid-washed lignin method modified by the filter bag is simpler and more precise.There were significant differences in the nutritional value of forage in different growth stages.The CNCPS system was used to analyze the protein and carbohydrate composition of forage at different growth stages.The soluble crude protein in the roughage was mainly non-protein nitrogen and the true protein content was relatively low.Alfalfa is high in crude protein,low in unusable protein and high in unstructured carbohydrate.The unusable fiber of grass forage is low and the unusable protein content is high.According to the data determined by milk system in 2016,the milk ton index and milk mu index of alfalfa were significantly higher than those of other grass forages.