Fermentation and aerobic stability of Napier grass silage treated with different levels of citric acid residue

Abstract

The experiment was conducted to investigate the effects of different levels of citric acid residue (CAR) on the fermentation quality and aerobic stability of Napier grass. Napier grass was ensiled with no additives control (CON), 1.2% CAR (C1), 3.6% CAR (C2) and 6.0% CAR (C3) on a fresh weight basis in laboratory silos for 3, 6, 9, 15 and 45 days. After opening the silos, the silages were subjected to analyzing the chemical and microbial compositions, and the residual silages ensiled for 45 days were evaluated for aerobic stability. Addition of CAR increased lactic acid/acetic acid, dry matter, lactic acid and water‐soluble carbohydrate contents, and decreased pH, acetic acid, ammonia nitrogen (NH3‐N), neutral detergent fiber, acid detergent fiber and cellulose contents as compared to the control. At the day 45 of ensiling, the C2 and C3 silages showed higher lactic acid contents and lactic acid/acetic acid, and lower NH3‐N and acetic acid contents than these of C1 silages. There was no significant difference in the aerobic stability between CAR‐treated silages and the control. Application of CAR effectively improved the fermentation quality of Napier grass, but had no obvious effects on the improvement of aerobic stability. In conclusion, application of CAR at the level of 3.6% or 6.0% is recommended for Napier grass silage making.

Dynamics of Bacterial Community and Fermentation Quality in Leymus chinensis Silage Treated With Lactic Acid Bacteria and/or Water

“…These results agree with the results of Zhang et al (2016) and Sun et al (2020), who reported declining organic acid concentrations in L. chinensis silage from 30 to 45 days and from 30 to 90 days, respectively. Other previous studies also observed the decline in rehydrated corn kernel silage (Carvalho et al, 2016), smooth bromegrass silage (Niu et al, 2018), barley silage (Liu et al, 2019), whole-plant corn silages treated with inoculants (Gharechahi et al, 2017;Guan et al, 2020;Xu et al, 2020), and Napier grass silage (Tao et al, 2021). These results suggest that the declining concentration of volatile components (organic acids and ammonia-N) during late fermentation is a universal phenomenon in silage and needs further research.…”

Effects of Lactic Acid Bacteria Additives on the Quality, Volatile Chemicals and Microbial Community of Leymus chinensis Silage During Aerobic Exposure

“…Lactic acid bacteria additives induce different types of fermentation Lactobacillus plantarum undergoes homolactic fermentation, while Lactobacillus buchneri undergoes heterogeneous fermentation (Addah et al, 2014;Li et al, 2021). The product of homolactic fermentation is lactic acid, which rapidly reduces the pH value of the silage, thereby inhibiting the activities of other microorganisms (Tao et al, 2021;Xie et al, 2021). However, in addition to lactic acid, heterogeneous fermentation also produces substances such as ethanol, acetic acid, and carbon dioxide, among which acetic acid can effectively inhibit the reproduction of harmful microorganisms (Si et al, 2018;Wang et al, 2021).…”

Sustainable Use of Pennisetum sinese: Effect on Nutritional Components and Fermentation Quality of Stylosanthes guianensis in Tropics

“…For the determination of counts of microorganisms, 10 g of fresh silage was tenfold serially diluted by 0.85% sodium chloride [33]. The population of the lactic acid bacteria (LAB) and the yeast were cultured in the MRS Agar medium and potato glucose agar medium, respectively.…”