Treatment of Whole-Plant Corn Silage With Lactic Acid Bacteria and Organic Acid Enhances Quality by Elevating Acid Content, Reducing pH, and Inhibiting Undesirable Microorganisms

Abstract

We investigated the variation in microbial community and fermentation characteristics of whole-plant corn silage after treatment with lactic acid bacteria (LAB) and organic acids. The fresh corn forages were treated with a combination of L. acidophilus and L. plantarum (106 CFU/g fresh material) or a 7:1:2 ratio of formic acid, acetic acid, and propionic acid (6 mL/g fresh material) followed by 45 or 90 days of ensiling. Silages treated with LAB showed increased lactic acid content and decreased pH after 45 days. Although treatment with LAB or organic acids decreased the common and unique operational taxonomic units, indicating a reduction in microbial diversity, the relative abundance of Lactobacillus was elevated after 45 and 90 days compared with control, which was more distinct in the organic acid groups. Moreover, we found higher levels of acetic acid and increased abundance of Acetobacter in silages treated with organic acids whereas undesirable microorganisms such as Klebsiella, Paenibacillus, and Enterobacter were reduced. In summary, the quality of corn silages was improved by LAB or organic acid treatment in which LAB more effectively enhanced lactic acid content and reduced pH while organic acid inhibited the growth of undesirable microorganisms.

Bacterial Succession Pattern during the Fermentation Process in Whole-Plant Corn Silage Processed in Different Geographical Areas of Northern China

“…Guan et al [2] and Gharechahi et al [12] also reported the unique bacterial community in whole-plant corn from different sampling sites. The abundance of Lactobacillus was 1.02%, 1.08% and 1.51% in H0, I0 and S0, respectively (Figure 3 and Supplementary Figure S1); the same results were reported by previous studies [2,[11][12][13][14][15]24,26]. This generally indicated that Lactobacillus is a minor taxon in whole-plant corn before ensiling.…”

The effects of replacement of berseem hay in total mixed rations with date palm leaves ensiled with malic or lactic acids at different levels on the nutritive value, ruminal in vitro biogas production and fermentation

“…This finding agrees the results of Kara [23] who observed that malic acid did not affect the composition of corn silage except decreased NDF contents. Similarly, Jiang et al [17] reported that whole plant corn ensiled with organic acid mixture (acetic acid, propionic acid, and formic acid at a 1:2:7 ratio) applied at 6 mL/g fresh material reduced NDF content in the silage. The decreased fiber content in organic acid-treated silages may be due to hydrolysis of digestible cell wall fractions by the action of organic acids during ensiling process [17,24].…”

“…Therefore, effective treatments of low-quality forages and materials can be used as a method of improving their nutritive value and chemical composition. Jiang et al [17] ensiled whole corn plant with organic acids and observed reduced NDF content in the silage. We hypothesized that malic acid or lactic acid treatment of DPL and RS during ensiling will raise the acidity rapidly, decrease the aerobic phase of fermentation, and accelerate the initiation of lag and anaerobic phases of silage, which may enhance the nutritional value of DPL and RS silage.…”

Fermentation Quality and Nutritional Traits of Cluster Bean-Maize Mixture Silages

“…Fermentation is a complex and dynamic process influenced by several factors including anaerobic conditions of the silo, quantity of water-soluble carbohydrates, abundance of epiphytic bacteria, dry matter quantity and buffering capacity of plant material (Weinberg and Muck, 1996). Different methods have been developed for efficient preservation of silage quality with the use of dry matters (Jiang et al 2020). High lactic acid content of graminae silages results in reduced silage pH, acetic, butyric and propionic acid contents and consequent formation of undesired harmful microbes for fermentation (Mohd-Setapar et al 2012;Salvucci et al 2016).…”