Project description:A healthy rumen is crucial for normal growth and improved production performance of ruminant animals. Rumen microbes participate in and regulate rumen epithelial function, and the diverse metabolites produced by rumen microbes are important participants in rumen microbe-host interactions. SCFAs, as metabolites of rumen microbes, have been widely studied, and propionate and butyrate have been proven to promote rumen epithelial cell proliferation. Succinate, as an intermediate metabolite in the citric acid cycle, is a final product in the metabolism of certain rumen microbes, and is also an intermediate product in the microbial synthesis pathway of propionate. However, its effect on rumen microbes and rumen epithelial function has not been studied. It is unclear whether succinate can stimulate rumen epithelial development. Therefore, in this experiment, Chinese Tan sheep were used as experimental animals to conduct a comprehensive analysis of the rumen microbiota community structure and rumen epithelial transcriptome, to explore the role of adding succinate to the diet in the interaction between the rumen microbiota and host.
Project description:Protozoa comprise a major fraction of the microbial biomass in the rumen microbiome, of which the entodiniomorphs (order: Entodiniomorphida) and holotrichs (order: Vestibuliferida) are consistently observed to be dominant across a diverse genetic and geographical range of ruminant hosts. Despite the apparent core role that protozoal species exert, their major biological and metabolic contributions to rumen function remain largely undescribed in vivo. Here, we have leveraged (meta)genome27 centric metaproteomes from rumen fluid samples originating from both cattle and goats fed diets with varying inclusion levels of lipids and starch, to detail the specific metabolic niches that protozoa occupy in the context of their microbial co-habitants. Initial proteome estimations via total protein counts and label-free quantification highlight that entodiniomorph species Entodinium and Epidinium as well as the holotrichs Dasytricha and Isotricha comprises an extensive fraction of the total rumen metaproteome. Proteomic detection of protozoal metabolism such as hydrogenases (Dasytricha, Isotricha, Epidinium, Enoploplastron), carbohydrate-active enzymes (Epidinium, Diplodinium, Enoploplastron, Polyplastron), microbial predation (Entodinium) and volatile fatty acid production (Entodinium and Epidinium) was observed at increased levels in high methane-emitting animals. Despite certain protozoal species having well-established reputations for digesting starch, they were unexpectedly less detectable in low methane emitting-animals fed high starch diets, which were instead dominated by propionate/succinate-producing bacterial populations suspected of being resistant to predation irrespective of host. Finally, we reaffirmed our abovementioned observations in geographically independent datasets, thus illuminating the substantial metabolic influence that under-explored eukaryotic populations have in the rumen, with greater implications for both digestion and methane metabolism.
Project description:Protozoa comprise a major fraction of the microbial biomass in the rumen microbiome, of which the entodiniomorphs (order: Entodiniomorphida) and holotrichs (order: Vestibuliferida) are consistently observed to be dominant across a diverse genetic and geographical range of ruminant hosts. Despite the apparent core role that protozoal species exert, their major biological and metabolic contributions to rumen function remain largely undescribed in vivo. Here, we have leveraged (meta)genome27 centric metaproteomes from rumen fluid samples originating from both cattle and goats fed diets with varying inclusion levels of lipids and starch, to detail the specific metabolic niches that protozoa occupy in the context of their microbial co-habitants. Initial proteome estimations via total protein counts and label-free quantification highlight that entodiniomorph species Entodinium and Epidinium as well as the holotrichs Dasytricha and Isotricha comprises an extensive fraction of the total rumen metaproteome. Proteomic detection of protozoal metabolism such as hydrogenases (Dasytricha, Isotricha, Epidinium, Enoploplastron), carbohydrate-active enzymes (Epidinium, Diplodinium, Enoploplastron, Polyplastron), microbial predation (Entodinium) and volatile fatty acid production (Entodinium and Epidinium) was observed at increased levels in high methane-emitting animals. Despite certain protozoal species having well-established reputations for digesting starch, they were unexpectedly less detectable in low methane emitting- 37 animals fed high starch diets, which were instead dominated by propionate/succinate-producing bacterial populations suspected of being resistant to predation irrespective of host. Finally, we reaffirmed our abovementioned observations in geographically independent datasets, thus illuminating the substantial metabolic influence that under-explored eukaryotic populations have in the rumen, with greater implications for both digestion and methane metabolism.
Project description:<p>From an animal production and health perspective, our understanding of the metabolites in ruminant biofluids, particularly rumen fluid across different host species is poorly understood. Metabolomics is a powerful and sensitive approach for investigating low molecular weight metabolite profiles present in rumen biofluids. It can be used to identify potential roles of metabolites in the rumen microbiome and provide and understanding of host-level regulatory mechanisms associated with animal production. The rumen is a strictly anaerobic environment enriched with a complex community of bacteria, protozoa, fungi, archaea and bacteriophages. Here, we present a metabolomic dataset generated using hydrophilic interaction liquid chromatography (HILIC) and semi-polar (C18) chromatography methods coupled to high resolution mass spectrometry (MS), collected in both positive and negative ionization modes, of ovine rumen samples that were fractionated based on molecular weight (20 kDa, 8-10 kDa and 100 Da). This study highlights the potential of HILIC and C18 chromatography combined with non-targeted mass spectrometric methods to detect the polar and semi-polar metabolite species of the ruminal fluid metabolome.</p>
Project description:Origanum oil (ORO), garlic oil (GAO), and peppermint oil (PEO) were shown to effectively lower methane production, decrease abundance of methanogens, and change abundances of several bacterial populations important to feed digestion in vitro. In this study, the impact of these essential oils (EOs, at 0.50 g/L), on the rumen bacterial community composition was further examined using the recently developed RumenBactArray.
Project description:Microbiome DNA from the adhering fraction of a sheep rumen. The RSTs were generated using an improved version of SARST (referred to as iSARST) from the microbiome DNA extracted from the adhering fraction of the rumen content taken from a sheep. The iSARST method is going to be submitted to Nature Biotechnology for publication. Keywords: other
Project description:Investigation of whole genome gene expression level changes in rumen epithelium of dairy cattle at different stages of rumen development and on different diets.