The Effects of Lactobacillus Plantarum, Bacillus Subtilis, Lignocellulolytic Enzyme System, and Their Combination on the Fermentation Profiles, Chemical Composition, Bacterial Community and Rumen Digestion of Fresh Waxy Corn Stalk Silage

Abstract

The objective of this study was to assess the impact of Lactobacillus plantarum, Bacillus subtilis and lignocellulolytic enzyme system on the nutritional value, fermentation profiles, rumen digestion, and bacterial community of fresh waxy corn stalk silage. Fresh waxy corn stalks harvested at 100 days of growth were treated with no additives (CON), compound multiple lactobacilli (ML, comprising Lactobacillus plantarum at 1.0 × 105 cfu/g fresh weight and Bacillus subtilis at 1.0 × 105 cfu/g fresh weight), lignocellulolytic enzyme system (LE, at 500g/t), and a combination of lignocellulolytic enzyme system and multiple lactobacilli (MLLE). The study found that all three treatments significantly reduced the NDF and ADF contents compared to CON (P < 0.001). LE most effectively increased ED in DM (P = 0.003) and NDF (P = 0.001), while MLLE showed the greatest increase in 'a' for DM (P < 0.001) and NDF (P = 0.001). The DM content in LE and MLLE was lower than in CON (P = 0.003), with a higher WSC content (P < 0.001). Both ML and MLLE produced more lactic acid than CON and LE (P < 0.001), resulting in a lower pH in these groups (P < 0.001). Additionally, the acetic acid content and NH3-N content was lower in ML and MLLE compared to CON and LE (P < 0.001). The counts of lactic acid bacteria (P < 0.001), yeast (P < 0.001), and mold (P = 0.004) declined over the fermentation period, dropping below detectable levels on the seventh and fifth days, respectively. Relative to CON, the three additives reduced the relative abundance of Weissella and Klebsiella and increased that of Lactobacillus. In conclusion, LE improved the nutritional value and rumen digestion of the silage, ML enhanced its fermentation profiles and bacterial community, and MLLE significantly improved the nutritional value, rumen digestion characteristics, fermentation profiles, and bacterial community of the fresh waxy corn stalk silage.

Keywords: Lactobacillus plantarum, Bacillus subtilis, cellulase, silage, fresh waxy corn stalk