Effects Of Different Fermentation Additives On Fermentation Quality Of Silage Oak Leaves And The Rumen In Vitro Fermentation Of Yanbian Yellow Cattle

This experiment was to study different additives on the silage fermentation quality of oak leaf,Yanbian yellow cattle rumen fermentation characteristics and the influence of the microbial flora in vitro fermentation,in order to screen the best fermentation additives,provide basis for the rational utilization of silage oak leaves in ruminants,and lay a foundation for the application and promotion of oak leaves as a new feed resource in animal husbandry.Experiment 1: Fresh oak leaves were used as raw materials,and different kinds of fermentation additives were added for silage fermentation,to study the effects of different fermentation additives on silage quality of oak leaves.The experiment was divided into 7 groups.The CK group was the control group without fermentation additives,and the experimental groups were supplemented with molasses,lactic acid bacteria,EM bacteria,1% lime water,lactic acid bacteria + molasses and EM bacteria + molasses,respectively,with 4 replicates in each group.After silage in dark place for 60 days,sensory measurement was carried out first,and then sampling was taken for analysis of various indicators.The results showed that the silage effect of M group,EM-M group and LAB-M group was the best from the perspective of sensory evaluation.EM-M group had the lowest p H,the highest lactic acid content,the highest LA/AA,the best Flieg score,and high silage quality.The silage quality of LAB-M group was slightly lower than that of EM-M group,and the overall performance was still high.No butyric acid was detected in silage oak leaves.Although LW group did not significantly improve silage quality,it could effectively reduce CT content.The contents of mold,yeast and aerobic bacteria in experimental groups were lower than those in control group,and the content of lactic acid bacteria increased significantly.The silage effect of fermentation additive test group was better than that of control group.Experiment 2: Four healthy Yanbian yellow cattle(443.3 kg ± 26.7 kg)with permanent rumen fistula were selected to provide rumen fluid.Oak leaves of the silage in accordance with the added divided into molasses fermentation additive group,the group of lactic acid bacteria,EM bacteria group,limewater,lactic acid bacteria + molasses group and EM bacteria + molasses group,to carry on the in vitro fermentation,cultivate 48 h,in the process of cultivation,at a certain time point(3 h,6 h,9 h,12 h,24 h,48 h)sampling,It is used for the determination of total gas production,p H,NH3-N content and volatile fatty acid content in in vitro fermentation,and to calculate the degradation rate of neutral detergent fiber,dry matter and crude protein.The results showed that the silage fermentation additive could significantly reduce the p H of rumen fermentation in yanbian cattle(P<0.05).The p H of LW group was significantly higher than that of control group(P<0.05).In vitro fermentation p H in LAB-M and EM-M groups was significantly lower than that in other groups(P<0.05).EM-M group had the highest total gas production in vitro.The gas production in LAB-M group was slightly higher than that in control group(P>0.05),and the gas production in other experimental groups was significantly higher than that in control group(P<0.05).The NH3-N content in M group,LAB group and EM-M group had no significant difference(P>0.05),but was significantly lower than that in CK group,LW group and EM group(P<0.05).There was no significant difference among LAB-M group,LAB group and EM-M group(P>0.05).Compared with the control group,the propionic acid content in experimental groups was significantly increased(P<0.05),and the AA/PA value was significantly decreased(P<0.05).LAB-M and EM-M groups showed advantages.Silage fermentation additives could improve rumen fermentation characteristics and improve production performance.Compared with the control group,the degradation rates of dry matter,crude protein and neutral detergent fiber in silage oak leaves experimental groups were significantly increased(P<0.05),and the degradation rates in EM and EM-M groups were the most significant increase,which could effectively improve feed utilization rate.Experiment 3: Rumen fluid obtained by 48 h in vitro fermentation was collected in Experiment 2,and total bacterial DNA was extracted for PCR amplification.Then,Illumina Hi Seq 2500 sequencing platform was used for high-throughput sequencing,to explore the effects of silage oak leaves with different fermentation additives on rumen microbial community of Yanbian yellow cattle.The results showed that: through multiple analysis at phylum level,genus level and OTU level,silage oak leaves with different fermentation additives had no adverse effects on the composition of microbial flora,microbial diversity and microbial abundance in rumen during in vitro fermentation of Yanbian yellow cattle.In conclusion,the silage quality of the fermentation additive test group is generally better than that of the control group.LAB-M and EM-M groups have a good effect on improving rumen fermentation characteristics and improving production performance.Degradation rates of dry matter,crude protein and neutral detergent fiber in EM and EM-M groups are significantly improved,which can effectively improve feed utilization rate.The experimental groups had no adverse effects on the overall composition of microbial flora,microbial diversity and microbial abundance in rumen of Yanbian yellow cattle.