Effects Of Harvest Period On The Silage Quality Of Wheat,Rye And Perennial Ryegrass

The objective of this paper was to study the nutritional quality of whole plant silage produced by different types of forage grass and explore suitable harvest periods.The experiment was carried out with wheat（Xinong 627）,rye（Dongmu 70）and perennial ryegrass（Maidi）as materials.The dry yield was determined in the blooming,filling,milk and dough stages of each variety,silage was prepared and crude protein（CP）,ether extract（EE）,crude fiber（CF）,ash（Ash）,nitrogen-free extract（NFE）,neutral detergent fiber（NDF）,acid detergent fiber（ADF）,acid detergent lignin（ADL）and relative feeding value（RFV）before ensiling and ensiled were determined,sensory evaluation of silage and pH,water soluble carbohydrate（WSC）,ammonia nitrogen（NH₃-N）were measured.The results showed that:（1）Different harvesting periods had different effects on the dry yield and the nutritional value before ensiling and ensiled of wheat,rye and perennial ryegrass.Wheat（Xinong 627）had the highest dry matter yield during the filling stage.With the delay of harvest,CP increased first and then decreased,the fiber content increased,and the NFE and RFV decreased.The dry yield of rye（Dongmu 70）increased with the delay of harvest,the highest in dough stage,CP decreased gradually after the highest blooming stage,CF and NFE increased.Perennial ryegrass（Maidi）had the highest dry yield during blooming.CP before ensiling and ensiled increased gradually with the harvest period,CF increased and NFE decreased.Xinong 627’s CP after silage was higher in blooming stage and dough stage.With the delay of harvest,the fiber content of the three forages showed a decreasing trend,the lowest in dough stage,and the NFE and RFV increased and the highest in dough stage.Maidi’s CF increased and NFE decreased than before ensiling.（2）Among the three forages,Dongmu 70 had the highest yield of hay.The CP content of Xinong 627 was higher than that of Dongmu 70 and slightly lower than that of Maidi.Xinong627 had the highest NFE content and the lowest fiber content,followed by Maidi,and Dongmu70 had the highest fiber content;Xiong 627 had the highest RFV,Dongmu 70 was lowest.（3）The harvest period had significant effects on the silage fermentation quality of wheat,rye and perennial ryegrass.As the harvest period was postponed,the pH of the three forages gradually increased,and NH₃-N and WSC increased first and then decreased and were lowest at the dough stage.（4）Xiong 627 had lower pH and NH₃-N,WSC were higher than Dongmu 70 and Maidi,and the fermentation quality was better,followed by rye（Dongmu 70）,and perennial ryegrass（Maidi）was poor.Comprehensive evaluation,this experiment considered that wheat,rye and perennial ryegrass were suitable for direct feeding during blooming stage,and suitable for silage utilization in dough stage.At this time,the content of crude protein and nitrogen-free extract was high,and the fiber content was low,the relative feeding value was high.The wheat variety Xiong 627 had the best comprehensive performance,and the silage had good nutritional quality.