Effects Of Rice Bran And Lactic Acid Bacteria Supplementation On The Fermentation Characteristic And Microbial Diversity Of Caragana Silage

In this study,Caragana korshinskii Kom.f and Caragana intermedia Kuang et H.C.Fu were selected in the bud and blooming stages,rice bran and lactic acid bacteria were added for silage to determine the nutritional quality,fermentation quality and microbial diversity,so as to provide theoretical basis for scientific and rational utilization of Caragana korshinskii resources.Growing respectively between 3 to 6 years of Caragana korshinskii and Caragana intermedia,after mechanical rubbing wire,crushing,control group and 3 group,without any additive as control group,experimental group were added 5%rice bran,adding 5%rice bran and commercial lactobacillus plantarum 2×105 cfu/g,adding 5%rice bran and L694 lactobacillus plantarum 3×105 cfu/g,silage fermentation room temperature 25? for 60 d.Nutritional quality,fermentation quality,organic acid content,in vitro digestibility and aerobic stability were measured.The effects of rice bran and lactic acid bacteria on the microbial diversity of Caragana korshinskii silage were compared by the second generation sequencing technology.The results showed that:(1)The soluble carbohydrate content of all the Caragana intermedia treatment groups was higher than that of the control group,among which the soluble carbohydrate content of the Caragana intermedia treatment group(S2-Z1)was the highest,2.83%.The contents of neutral washing fiber and acid washing fiber in all treatment groups were lower than those in the control group,and the lowest values were found in the treatment group with rice bran and L694(S2-Z3)at the flowering stage,which were 61.2%and 45.56%,respectively.After 60 days of fermentation,the pH value and ammonia nitrogen content were the lowest in the S2-Z3 treatment group,3.98%and 1.03%,respectively.In vitro dry matter digestibility(IVDMD)was the lowest in the bud stage control group(S1-Con),with a significant difference between growth stages,but no interaction.In vitro neutral detergent fiber digestibility(IVNDFD)was the highest in the S2-Z3 treatment group,29.97%,with no interaction between different growth stages and different treatments.Lactic acid content was the highest in the L694 lactobacillus plantarum group,10.66%and 10.19%,respectively,with significant differences between the treatments(P<0.05),the highest value of lactic acid/acetic acid was in the S2-Z3 treatment group,up to 6.09,with significant difference and interaction between the treatments.Compared with the control group,the treatment groups all increased the microbial diversity.The S1-Con control group and the S1-Z3 treatment group had more lactic acid bacteria,and a small number of Pantoea bacteria were generated,while the S1-Z1 treatment group and S1-Z2 treatment group had more Enterococcus and Kosakonia bacteria.The group treated with S2-Z3 had the most abundant microbial diversity.The comprehensive analysis showed that the fermentation effect of S2-Z1 and S2-Z3 was the best.(2)After 60 days of silage of Caragana korshinskii in bud stage and blooming stage,the pH value of the treatment groups of P1-N2 and P2-N2 was the lowest,both less than 4.2,and the quality was good.The content of ammonia nitrogen was the lowest in the treatment group of L694(P2-N3)at flowering stage,which was 1.17%.After adding rice bran and lactobacillus,the content of soluble carbohydrate in the treatment group was significantly higher than that in the control group,and there was an interaction.The content of neutral washing fiber and acid washing fiber in the treatment group was higher than that in the control group,and the content of P2-N1 treatment group was the lowest,51.08%.The highest IVDMD was found in the P2-N1 treatment group,59.61%,and the lowest in the control group,46.82%and 46.83%,respectively.(P<0.05),there was interaction,and the highest value in the IVDNFD P1-N2 treatment group was 29.16%.There was significant difference between different growth stages and there was interaction.The content of lactic acid was the highest in the N2 treatment group,9.29%and 9.93%,respectively,and the content of P1-Con was the lowest,5.77%.(P<0.05),the acetic acid content of the flowering group was lower than that of the gestational bud treatment group,and there was an interaction between different growth stages and different treatments.The lactic acid/acetic acid value at stage P2 was all greater than 5,higher than the ratio at stage P1.The highest lactic acid/acetic acid value was in the P2-N1 treatment group,which was 5.68.The optimal fermentation effect of P2-N2 and P2-N3 was analyzed.