Study On The Culture Technology And Ferment Effect Of Lactobacillus From Silage

To investigate the effects of two inoculations on corn silage fermentation, microbial contents, and milk production, 2 strains of lactic acid bacteria, -identified as Lactobacillus fermentum strain 44197 and Lactobacillus plantarum strain KLDS by the method of 16SrDNA were screened from silage.Experiment 1 was conducted to optimize the culture conditions for the growth of GLP01, Lactobacillus plantarum, and BLF01, Lactobacillus fermentum. Response surface methodology (RSM) was applied for the critical medium components (carbon source, nitrogen source, initial pH, temperature and inoculum size) identified earlier by one-factor-at-a-time approach. Using this methodology, the optimal carbon source and nitrogen source of GLP01 were fructose and yeast powder. Using RSM, the optimal culture conditions of GLP01were pH 5.47, temperature 35.3℃, inoculum size 8.16%; The optimal carbon source and nitrogen source of BLF01 were lactose and yeast powder, the optimal culture conditions were pH 8.0, temperature 35℃, inoculum size 1%.Experiment 2 was designed to study effects of the two microbial inoculants on corn silage fermentation, nutritive value and microbial contents. Corn was treated with nothing(CK), or L.plantarum (G), or L.fermentum (B), or L.plantarum+L.buchneri (LG), at a final application rate of 105 cfu/g of fresh forage and ensiled in laboratory silos for 1,3,5,7,9,12,15,30,45,60,90 d. Treatment with Lactobacillus plantarum had effects on the end products of fermentation, which increased the amount of LAB (P<0.05), decreased the amount of fungus (P<0.05), and markedly decreased pH value when compared to untreated silage. Treated with L. fermentum had a higher concentration of lactic acid (6.42% vs. 5.57%) but lower acetic acid (9.08% vs. 12.68%) than untreated silage. Treating corn silage with L.plantarum+L.buchneri markedly decreased the pH value (P<0.01), and the ratio of lactic acid to acetic acid of this group was 2.01, but the group of CK, G, and B was 6.69, 9.27 and 8.05 respectively.Experiment 3 was designed to study the effect of L.plantarum and L.buchneri on milk production under field conditions. The milk production increased 2.21kg/d and 0.3kg/d-when treated with L.plantarum and L.buchneri respectively. Treated with L.plantarum and L.buchneri markedly increased the fat percentage (P<0.05).