| Lactic acid bacteria silage additives, a kind of microbial additives, is specially used for ensiling to regulate microbial flora in silage forage, control silage fermentation process and improve the conversion efficiency of polysaccharides and crude fiber. Therefore, silage quality is increased effectively.L-1 Lactobacillus which was screened from 7 lactobacillus strains could produce the most amount of lactic acid. In this study, the fermentation condition of L-1 Lactobacillus was first optimized; then the application of lactic acid bacteria silage additives aiming at easy-ensilaged (e.g. whole-plant corn) and hardy-ensilaged (e.g. ryegrass) was investigated; finally production technique about lactic acid bacteria silage additives was determined.Through single factor experiments and orthogonal test , the optimal cultural conditions of L-1 Lactobacillus were as follows:initial pH being 6.5, cultural inoculum amount being 5 % and temperature being 35~40℃.The optimal composition of culture medium was MRS culture medium plus 5% tomato juice, 15 % carrot juice and 0.01% L-cysteine hydrochloride.Ryegrass was ensiled at 23±2℃ to evaluate the effects of lactobacillus, lactococcus and cellulase on fermentation quality. Ryegrass was treated with addition of single lactobacillus, lactobacillus plus lactococcus and lactobacillus plus cellulase respectively, silage with no additives served as a control. Results showed that supplementation of single lactobacillus and lactobacillus plus lactococcus didn't influence pH (P >0.05)of silage, but fermentation quality were improved slightly compared with that of control group. The pH of Lactobacillus plus cellulase group decreased (P <0.05) significantly during the whole silage fermentation, compared with control group, the lactic acid content was increased greatly (P <0.01), the contents of NH3-N (P <0.05), NDF (P <0.01)and ADF (P <0.05) were reduced significantly, protein loss was decreased by 8 %, but the concentration of butyric acid was a little higher in lactobacillus plus cellulase group than others groups. It was concluded that addition of lactobacillus plus cellulase might improve the fermentation quality of ryegrass silage significantly.Whole-plant corn was ensiled at 25±2℃ to evaluate the effects of lactobacillus, pediococcus and cellulase on fermentation quality. The following results were obtained: 1. Supplied with single lactic acid bacteria and multiple lactic acid bacteria, the silage corn attained good silage standard with pH of silage between 4.1 and 4.3. Addition of multiple lactic acid bacteria didn't decease DM loss and protein loss during ensiling , but silages treated with single lactic acid bacteria protein loss was decreased by 13 % and DM loss was 4/5 that of control group, NDF and ADF(P <0.01)were reduced significantly. It was concluded that single lactic acid bacteria might improve the fermentation quality and nutrition value of corn silage.2. Addition of cellulase increased DM loss during corn ensiling, compared with control group, the NDF and ADF contents were decreased by 4.8 % and 9.2 % respectively, protein loss was decreased by 18.2 %.lactic acid content was 5.1 times that of control group ,but acetic acid content was increased (P <0.01).It was showed that addition of cellulase accelerated heterofermentation and reduced fermentation quality of corn silage. 3. After treating whole-plant corn with lactic acid bacteria and cellulase of different contents, the pH of silage were between 3.5 and 3.9 and attained high-grade silage standard. Compared with control group, the contents of NDF and ADF (P <0.01)were reduced significantly, the lactic acid content was increased greatly (P <0.05) , protein loss was decreased (P <0.05), lower ratio ammonia nitrogen to total nitrogen(NH3-N/TN)were obtained.But addition with redundant content of cellulase could make fiber degraded excessively and increase DM loss during corn ensiling. It was concluded that addition of lactic acid bacteria and suitable content of cellulase may improve the fermentat...
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