Quality Evaluation Of Alfalfa Silage On Large-Scale Pastures In Hebei,Inner Mongolia,Liaoning,Gansu,Ningxia

(Objective)The alfalfa silage can not only provide cows with high-quality fiber and high-quality protein sources,but also the alfalfa silage is the key to solving the difficulties in the preparation of alfalfa hay in China and the shortage of high-quality forage in China.The purpose of this experiment is to study the current status and overall quality of alfalfa silage in large-scale pastures in Hebei,Inner Mongolia,Liaoning,Gansu and Ningxia.?Method?Randomly select large-scale pastures in Hebei,Inner Mongolia,Liaoning,Gansu and Ningxia,and investigate and research alfalfa silage from June to December 2019.A total of 125 alfalfa silage samples were collected.The production status of alfalfa silage,the quality status of each pasture,and the quality status of representative silage in the pasture at different heights were studied respectively.The main research results are as follows:?Results?The study showed:1.The basic condition of alfalfa silage in Jimeng,Liaoning,Gansu and Ningxia.?1?53.33%of the alfalfa silage harvested in Liaoning,Gansu,Ningxia and Liaoning provinces were harvested in one crop,26.67%in the second crop,and 20.00%in the three crops.?2?13.33%of alfalfa silage is harvested during the vegetative period,20%is harvested during the bud period,53.33%is harvested during the early flowering period?10%flowering?,and 6.67%is harvested during the flowering period?50%flowering?.Harvest during the full bloom period accounted for 6.67%.?3?When harvesting alfalfa silage,the cutting length is less than1.5 cm and the proportion is 0,1.5-2.4 cm is 33.33%,2.5-4 cm is 53.33%,and more than 4 cm is 13.33%.?4?the amount of alfalfa silage in the TMR daily feed?DM basis?,the amount of less than 5%accounts for 6.67%,the amount of 5-10%accounts for73.33%,the amount of 11-20%accounts for 13.33,the amount of More than 20%accounted for 6.67%.?5?All pastures use a single silage,and no silage is used for mixing with other crops.In terms of additive use,all pastures use additives,of which 2pastures use both lactic acid bacteria additives and organic acid additives.Lactic acid bacteria additives were used in the pastures.No enzyme preparations,green juice fermentation broths,inorganic acid additives and sugars were used in the pastures.In terms of the source of the additives,the percentage of pastures using domestic additives was 47%,and the proportion of pastures using imported additives was 53%.2.Jimeng Liaoning Ganning alfalfa silage quality status:?1?Among the inspection indexes of alfalfa silage quality,DM,NDFD,Ash,WSC,LA,AA,PA and BA were the most variable,which were 12.75%,15.06%,19.79%,51.85%,29.11%,57.41%,45.21%and 61.68%respectively.?2?The percentages of alfalfa silage samples with excellent,good,medium,and spoiled fermentation quality in the five areas of Hebei,Mongolia,Liaoning,Gansu,and Ningxia accounted for 3.4%,65.52%,31.03%,and 0of the total samples,respectively.?3?Analyze the quality of alfalfa silage in the five areas of Hebei,Mongolia,Liaoning,Gansu and Ningxia by principal component analysis and cluster analysis.Alfalfa in 5 pastures in Shijiazhuang,Luquan,Chifeng and Shenyang,Hebei Province The quality of silage is among the top five of the 29pastures,with the best quality.Followed by Wen'an County of Hebei Province,Hohhot City of Inner Mongolia,Shenyang City,Dandong City,Kuandian County of Liaoning Province and Zhangye City of Gansu Province.?4?In the detection of aflatoxin B₁,all the pastures were not detected.?5?The random variation model was used to analyze the daily variation of alfalfa silage quality between pastures and in the pastures.The daily variation among pastures accounted for 9.1-21.4%of the total variation.The daily variation of the contents of DM,CP,ADF,NDF,NDFD,Ash and EE in the pasture was 14.5%,9.1%,12.8%,13.5%,14.4%,21.4%and 11.5%.3.Analysis of compaction and quality of alfalfa silage at different heights in large silos.With the increase of silage depth,the alfalfa silage significantly increased wet density?P<0.05?.The dry matter density increased first and then decreased,and the dry matter density reached a maximum at a depth of 160 cm.With the increase of the depth,the sensory evaluation of alfalfa silage The score of the scoring system increased first and then decreased.The depth of 160 cm was significantly higher than other depths?P<0.05?.With the increase of depth,the DM content showed a downward trend.The depth above 40 cm was significantly higher than the depth of 80-160 cm?P<0.05?,the depth of 80-160 cm is significantly higher than the lower layer?P<0.05?;CP content is not significantly different between the depths,but the overall trend is that as the depth increases,the CP content decreases first and then increases,and 10 cm?330 cm depth?decreased again near the bottom of the pit;the pH value decreased significantly with increasing depth?P<0.05?.?Conclusions?:The production status and quality of alfalfa silage vary greatly among pastures,and there is still much room for improvement in the quality of silage.