Dynamic Variations in Rumen Fermentation Characteristics and Bacterial Community Composition during In Vitro Fermentation

Abstract

This study aimed to explore the dynamic variations of rumen fermentation characteristics and bacterial community composition during a 24 h in vitro fermentation. A total of twenty-three samples were collected from original rumen fluid (ORF, n = 3), fermentation at 12 h (R12, n = 10), and fermentation at 24 h (R24, n = 10). Results showed that gas production, concentrations of microbial crude protein, ammonia nitrogen, and individual volatile fatty acids (VFA), as well as total VFA and branched-chain VFA concentrations, were higher in R24 when compared with R12 (p < 0.05). However, no significant differences were observed in acetate to propionate ratio and fermentation efficiency between R12 and R24 (p > 0.05). Bacterial diversity analysis found that Shannon index and Simpson index were higher in R24 (p < 0.05), and obvious clusters were observed in rumen bacterial community between R12 and R24. Taxonomic analysis at the phylum level showed that the abundances of Proteobacteria and Fibrobacteres were higher in R12 than that in R24, and inverse results were observed in Bacteroidetes, Firmicutes, Cyanobacteria, Verrucomicrobia, Lentisphaerae, and Synergistetes abundances. Taxonomic analysis at the genus level revealed that the abundances of Rikenellaceae RC9 gut group, Succiniclasticum, Prevotellaceae UCG-003, Christensenellaceae R-7 group, Ruminococcaceae UCG-002, Veillonellaceae UCG-001, and Ruminococcaceae NK4A214 group were higher in R24, whereas higher abundances of Succinivibrionaceae UCG-002, Ruminobacter, and Fibrobacter, were found in R12. Correlation analysis revealed the negative associations between gas production and abundances of Proteobacteria, Succinivibrionaceae UCG-002, and Ruminobacter. Moreover, the abundances of Firmicutes, Rikenellaceae RC9 gut group, Christensenellaceae R-7 group, and Ruminococcaceae UCG-002 positively correlated with VFA production. These results indicate that both rumen fermentation characteristics and bacterial community composition were dynamic during in vitro fermentation, whereas the fermentation pattern, efficiency, and bacterial richness remained similar. This study provide insight into the dynamics of rumen fermentation characteristics and bacterial composition during in vitro fermentation. This study may also provide a reference for decision-making for the sampling time point when conducting an in vitro fermentation for bacterial community investigation.

Amylopectin Partially Substituted by Cellulose in the Hindgut Was Beneficial to Short-Chain Fatty Acid Production and Probiotic Colonization

“…N -glucan synthesis ability was also strengthened in the Amycel vivo group: N -glucan is an important signal molecule in disease regulation and a vital nutrient for hindgut fermentation, which supplies energy for colonic epithelial cells ( 49 , 50 ). Christensenellaceae_R7_group and Terrisporobacter were believed to be SCFA-producing bacteria in previous studies ( 51 – 53 ), but they were negatively correlated with acetate and butyrate in this study. Colinsella in the hindgut was also negatively correlated with butyrate in this study.…”

>b<Metabolism, and rumen microbiome of Nellore beef cattle submitted to intensified grazing systems during different season>/b<

“…In our assay, relative abundance (%) of the Prevotella was 17.17% higher on rumen of animals during Winter when compared to Summer, for instance. Findings on literature corroborate our findings (Pandit et al, 2018;Xie et al, 2019;Daghio et al, 2021;Wei et al, 2022) which shows that not only Prevotella, but also Rikenellaceae RC9 gut group were in between the most abundant genera in rumen of grazing animals.…”

The gas production, ruminal fermentation parameters, and microbiota in response to Clostridium butyricum supplementation on in vitro varying with media pH levels

“…The results were consistent with the experiment conducted by Jiao et al (2019) , who observed an increase in the GP, DMD, total VFA concentration, and A:P ratio from low (5.8) to high media pH (6.5) in batch culture using a diet containing 60% forage. In addition, our outcomes revealed that phylum Proteobacteria involved in fibre digestion ( Qiu et al, 2020 ; Wei et al, 2022 ) and its relative abundance was decreased at media pH 6.0 compared with pH 6.6, indicating an inhibition effect of low media pH on fibre digestion. Thus, the varied results of GP, DMD and fermentation characteristics could be attributed to the inhibition of growth of phylum Proteobacteria at low media pH vs .…”