Effects Of Variety And Harvest Period On The Quality Of Corn Silage

The objective of this paper was to study the nutritional quality of whole plant silage produced by different types of corn and explore suitable harvest periods.Corn types‘silage maize?Zhongyuandan 32?',‘waxy corn?Tiannuo 2?',and‘grain corn?Zhengdan 958?'were harvested at milk stage,dough stage and ripe stage.Determined the dry matter yield,the content of crude protein,crude fiber,crude fat,crude ash,NDF,ADF and lignin of the whole plant before ensiling and after ensiling,and calculate relative feed value;Simultaneously determined the pH value,the content of NH₃-N,WSC lactic acid and acetic acid to identify the quality of silage fermentation quality.The result showed that:?1?The highest dry matter yield occured at dough stage,which was significantly higher than that of milk stage and ripe stage?P<0.05?.At dough stage,crude protein content reached the highest,and the contents of CF,NDF,and ADF was observed gradually decreased with the delay of the harvest period.?2?Among the three types of corn,‘waxy corn?Tiannuo 2?'had the highest dry matter yield and the lowest contents of NDF,ADF and lignin.‘silage maize?Zhongyuandan 32?'had the highest crude protein content and relative feed value.The washed fiber content was low;The relative feed value of‘grain corn?Zhengdan 958?'was lower and the fiber content was higher.?3?There was differences on silage fermentation quality among varieties.After ensiling,‘waxy corn?Tiannuo 2?'had the highest WSC and lactic acid content.The pH value was less than 4,the quality of silage was good.The silage quality of‘silage maize?Zhongyuandan32?'was inferior to‘waxy corn?Tiannuo 2?',and‘grain corn?Zhengdan 958?'silage quality is poor.?4?Harvest periods had a significant effect on the quality of silage fermentation.With the delay of harvest,pH,NH3-N content increased,WSC,lactic acid content decreased.At the milk stage,pH,NH₃-N content was the lowest,WSC and lactic acid content were the highest,the fermentation quality was the best.Considering the effect of varieties and harvest period on nutritional value and fermentation quality of corn,the study showed that‘waxy corn?Tiannuo 2?'was similar in quality to‘silage maize?Zhongyuandan 32?',it has good quality for silage production,the most suitable harvest period is the dough stage for corn silage.