Isolation And Screening Of Lactic Acid Bacteria From Corn Silage And The Effect Of Adding It On Corn Silage Quality And Aerobic Stability

In order to study the effect of applying lactic acid bacteria on corn silage fermentation quality and aerobic stability, this experiment selects Lactobacillus alimentarius and Lactobacillus fructosus of 12 corn ensilaging samples from 4 districts of Inner Mongolia, and takes these extracts as either a single additive or a combined additive back into the corn silage. This experiment aims to provide a theoretical guidance for the development of new additive products and a reasonable choice of additive doses in production. The study also provides a theoretical basis for silage fermentation process and aerobic stability.This study indicates that:1. There were different types of lactic acid bacteria in corn silage in different regions of Inner Mongolia. The species and number of Lactobacillus were more than those of Lactococci. The acid production and the growth performance of various strains were significantly different from each other. This study selected two excellent types of Lactobacillus, which were Lactobacillus alimentarius and Lactobacillus fructosus.2. At the end of the silage fermentation, CP content of L.alimentarius +L.fructosus group was significantly higher than the control group and the L.fructosus group (P<0.01). Ammonia nitrogen was obviously lower than the control group and the L.fructosus group (P<0.05). After silage, DM content of each group largely decreased, and NDF and ADF content significantly increased (P <0.01). NDF and ADF of L.fructosus group and L.alimentarius + L.fructosus group were apparently higher than the other two groups (P <0.05).3. PH value of each group has declined after silage. PH value of L.alimentarius + L.fructosus group was significantly lower than the control group (P <0.05). Lactic acid and acetic acid content of L.alimentarius + L.fructosus group were obviously higher than the control group (P <0.05). The acid content in each group no significant difference. The number of lactic acid bacteria increased after silage. Yeasts and molds were not found in the 3 treatment groups.4. With the extension of aerobic exposure time, the pH value of each group increased. PH value of L.alimentarius + L.fructosus group was always largely 5. lower than the control group (P <0.05). The number of lactic acid bacteria declined; instead, the number of yeasts and molds increased. On the seventh day of the exposion in air, the largest number of lactic acid bacteria appeared in L.alimentarius group. The number of yeasts and molds in the L.alimentarius + L.fructosus group was the least and.6. During the aerobic stability trial period, the acetic acid content of L.fructosus group was always significantly higher than the other groups (P <0.05). The lactic acid and VFA of L.alimentarius + L.fructosus group remained a lot. The content of various organic acids were significantly higher (P <0.05). The WSC and DM in each group declined in various degree. NDF and ADF did not change a lot.