Effects of Sodium Formate and Calcium Propionate Additives on the Fermentation Quality and Microbial Community of Wet Brewers Grains after Short-Term Storage

Abstract

The objective of this research was to examine the effect of sodium formate (SF) and calcium propionate (CAP) on the fermentation characteristics and microbial community of wet brewers grains (WBG) after short-term storage. In the laboratory environment, fresh WBG was ensiled with (1) no additive (CON), (2) sodium formate (SF, 3 g/kg fresh weight), and (3) calcium propionate (CAP, 3 g/kg fresh weight) for 20 days. After opening, fermentation characteristics, chemical composition, rumen effective degradability, and the microbial community of ensiled WBG were analyzed. The addition of CAP had no effect on pH and lactic acid concentration and increased the concentrations of propionic acid; the SF group had the lowest pH and acetic acid, butyric acid, and ammonia nitrogen contents and the highest lactic acid concentration. After fermentation, the SF group had the highest contents of dry matter (DM), water-soluble carbohydrates (WSCs), and neutral detergent fiber (NDF). The contents of the three nutrients in the CAP group were significantly higher than those in the CON group. The addition of the two additives had little influence on the crude protein (CP) and acid detergent fiber (ADF) contents of the ensiled WBG. Two additives elevated in situ effective degradability of DM and NDF compared with the parameters detected in the CON group; WBG ensiled with SF had higher effective in situ CP degradability than that in the CON and CAP groups. The results of the principal component analysis indicate that the SF group and two other groups had notable differences in bacterial composition. The analysis of the genus level of the bacterial flora showed that the content of Lactobacillus in the SF group was significantly higher than that in the two other treatment groups, while the content of Clostridium was significantly lower than that in the two other treatment groups. Therefore, the addition of sodium formate can suppress the undesirable microorganisms, improve the fermentation qualities, and ensure that WBG is well preserved after 20 days of ensiling.

Protease-Producing Lactic Acid Bacteria with Antibacterial Properties and Their Potential Use in Soybean Meal Fermentation

“…Clostridia spp. is the main species causing spoilage of protein feed because of its potential to cause DM loss and butyric acid production, thereby promoting the growth of less-acid-resistant putrid microorganisms and thus resulting in reduced feed intake [40]. In this study, no clostridium was found in other groups except for that protease-treated for 36 h and 12 d. This is further evidence that enzymatic treatment may pose the risk of contamination and energy loss for the fermentation feed.…”

Effect of cellulase and lactic acid bacteria on the fermentation quality, carbohydrate conversion, and microbial community of ensiling oat with different moisture contents

“…The pH was negatively correlated with the abundance of Lactiplantibacillus ( P < 0.05), consistent with the research result reported by Mu et al (2020) , and was mainly attributed to the metabolites of LAB that could rapidly acidize the silage. It is well known that rapid acidification provides a critical effect in inhibiting unfavorable microbial activity and preserving nutrients ( Lv et al, 2020 ). As expected, we found that Lactiplantibacillus in this study was negatively correlated with NH 3 -N concents and positively correlated with CP content, whereas the opposite was observed for Clostridium_sensu_stricto_12 , which demonstrates the important role of LAB in inhibiting protein breakdown.…”

Effects of wet brewers grains on fermentation quality and in vitro ruminal digestibility of mixed silage prepared with corn stalk, sweet potato peel and dried apple pomace in southeast China

“…In vitro culture has been conducted as a common method to evaluate the nutrient values of ruminant feeds (Lv et al, 2020). The IVDMD was an important parameter that reflected the rate of feed utilisation in the rumen, and the digestion of DM mainly included carbohydrates, proteins and other substances (Li et al, 2014).…”

“…The pH was an important parameter to evaluate fermentation quality and the target pH for quality silage is less than 4.20 (Lv et al, 2020). In the experiment, the pH in all silages had a numerical drop to below 4.20 and subsequently kept stable, which was considered an indication of quality silage.…”

“…In vitro culture has been conducted as a common method to evaluate the nutrient values of ruminant feeds (Lv et al, 2020). The IVDMD was an important parameter that reflected the rate of feed utilisation Abbreviations: B-L, linear effect of wet brewers grains proportions; B-Q, quadratic effect of wet brewers grains proportions; DM, dry matter; FW, fresh weight; GP, 72 h cumulative gas production; IVDMD, in vitro dry matter digestibility; IVCPD, in vitro crude protein digestibility; IVNDFD, in vitro neutral detergent fibre digestibility; ME, metabolisable energy; Potential GP, potential gas production; Rate constant of GP, rate constant of gas production; SEM, standard error of the mean; T, treatments.…”