Silage Fermentation, Bacterial Community, and Aerobic Stability of Total Mixed Ration Containing Wet Corn Gluten Feed and Corn Stover Prepared with Different Additives

Abstract

The objective of this study was to investigate the effects of different additives on the fermentation quality, bacterial community, and aerobic stability of total mixed ration (TMR) silage containing wet corn gluten feed (WCGF) and corn stover. The TMR was ensiled with four treatments: (1) no additive (control); (2) lactic acid bacteria (LAB); (3) fibrolytic enzyme (EN); (4) LAB + EN. The EN and LAB + EN decreased the neutral detergent fiber and acid detergent fiber contents. Additives led to a higher lactic acid (LA) content (p < 0.0001) compared to control at all ensiling times. Silages inoculated with LAB and LAB + EN had higher dry matter (p = 0.0007), LA (p < 0.0001) and acetic acid (AA) contents (p < 0.0001) compared to control. The LAB and LAB + EN had significantly lowest ammonia nitrogen among the treatments, while no significant difference occurred after days 7 of ensiling. Silages treated with LAB and LAB + EN had a higher LAB count (p < 0.0001) and a lower pH, yeast, and mold counts compared to other silages. The LAB and LAB + EN greatly increased the portions of Firmicutes and Lactobacillus (p < 0.0001, and p < 0.0001, respectively) and reduced undesirable bacteria. Inoculation with LAB + EN and LAB improved aerobic stability of TMR silages indicated by higher and more stable LA and AA contents, smaller rise in pH, and yeast count than other silages. The LAB + EN and LAB reduced microbial diversity and improved the fermentation quality and aerobic stability of TMR silage containing WCGF and corn stover.

Effects of growth stage on the fermentation quality, microbial community, and metabolomic properties of Italian ryegrass (Lolium multiflorum Lam.) silage

“…Alpha diversity represents the richness and diversity of species in ecosystems, and the Ace and Chao 1 indices are used to measure the richness of species, and the lower the index, the lower the richness. The Shannon index is used to measure species diversity, and the lower the index, the lower the diversity of species (Zhang et al, 2020). In the present study, Ace, Chao 1 and Shannon indexes decreased after ensiling, indicating that the richness and diversity of bacterial communities decreased after ensiling.…”

Effects of different harvest frequencies on microbial community and metabolomic properties of annual ryegrass silage

“…Shannon’s index is used to measure species diversity, and a larger Shannon index indicated higher species diversity in the sample. Ace and Chao 1 indices are used to measure species richness, and lower Ace and Chao 1 index values indicated lower species richness of the sample ( Zhang et al, 2020 ). Moreover, the Shannon index, Ace index, and Chao 1 index showed trends similar to the trend of the Sobs.…”

“…Our findings are consistent with those of Ren et al (2020) , who discovered that the Chao 1 and Ace indices of sugarcane top silages were lowest at the end of fermentation, implying that the diversity of the microbial community may have declined as LAB became dominant in the silage. The Sobs, Shannon, Ace, and Chao 1 indices were lowest for the second harvest silage, which indicated that there may have been a small number of acidifying bacterial species in the second harvest silage ( Zhang et al, 2020 ). The variation in the microbial community was further elucidated by analyzing the β-diversity of the bacterial population.…”

Short Communication: Prognostic Values of a Multiparametric Risk Score in Maize Silage Undergoing Different Ensiling Conditions

“…The aerobic stability of maize silage depends on several factors, such as the use of Lb, the presence of oxygen, and a sufficient number of aerobic organisms (yeasts, molds, bacteria) and available substrates (sugars, starches, organic acids), a temperature > 4 • C and a DM content < 800 g/kg [29]. The obligate heterofermentative inoculants use lactic acid to produce acetic acid [7], primarily inhibiting the yeast activity responsible for the beginning of the aerobic spoilage [30]. The choice of the use of Lb among other possible species was related to its ability to increase the number of hours that a TMR remains stable when exposed to air and without any effects on DM intake or milk production [31].…”