Project description:As the unique organ, rumen plays vital roles in providing products for humans, however, the underlying cell composition and interactions with epithelium-attached microbes remain largely unknown. Herein, we performed an integrated analysis in single-cell transcriptome, epithelial microbiome, and metabolome of rumen tissues to explore the differences of microbiota-host crosstalk between newborn and adult cattle models. We found that fewer epithelial cell subtypes and more abundant immune cells (e.g., Th17 cells) in the rumen tissue of adult cattle. Metabolism-related functions and oxidation-reduction process were significantly upregulated in the adult rumen epithelial cell subtypes. The epithelial Desulfovibrio was significantly enriched in the adult cattle. To further clarify the role of Desulfovibrio in host’s oxidation-reduction process, we performed metabolomics analysis of rumen tissues and found that Desulfovibrio showed a high co-occurrence probability with the pyridoxal in the adult cattle compared with newborn ones. The adult rumen epithelial cell subtypes also showed stronger ability of pyridoxal binding. These indicates that Desulfovibrio and pyridoxal likely play important roles in maintaining redox balance in adult rumen. The integrated analysis provides novel insights into the understanding of rumen function and facilitate the future precision improvement of rumen function and milk/meat production in cattle.
Project description:RNA sequencing (RNA-Seq) was performed on rumen papillae from 16 steers with variation in gain and feed intake. Sixteen rumen papillae samples were sequenced by Cofactor Genomics (St.Louis, MO).
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:Four mature, non-lactating dairy cattle were transitioned from a high forage diet (HF; 0% grain) to a high grain diet (HG; 65% grain) that was fed for three weeks. Rumen papillae biopsies were performed during the HF baseline (week 0) and after the first (week 1) and third week (week 3) of the grain challenge to create a transcript profile for the the short and long-term adaption of the rumen epithelium during ruminal acidosis. Comparison between three weekly means (n=4 for each week, 12 arrays in total)
Project description:The transcriptome of Escherichia coli K-12 has been widely studied over a variety of conditions for the past decade while such studies involving E. coli O157:H7, its pathogenic cousin, are just now being conducted. To better understand the impact of rumen fluid on E. coli O157:H7, global transcript levels of strain EDL933 cells resuspended in heat clarified rumen fluid for 15 min were compared to cells resuspended in fresh LB using microarrays. Seven independent RNA samples from rumen fluid treated cultures were paired with seven independent RNA samples from control cultures for hybridization to seven two-color microarrays. For three arrays, the control RNA sample was labeled with Cy3 dye and the experimental RNA sample was labeled with Cy5 dye, the dyes were reversed for the other four arrays to overcome dye bias.
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:AIMS: To explore and validate the utility of rumen endoscopy for collection of rumen papillae for gene expression measurement. METHODS: Four adult Coopworth ewes were fasted for either 4 or 24 hours. Animals were sedated, placed in a dorsally recumbent position at 45 degrees with the head upright, and an endoscope inserted via a tube inserted into the mouth. Biopsies of rumen papillae were taken from the ventral surface of the rumen atrium under visual guidance. Two biopsies were collected from one of the animals that had been fasted for 4 hours, and three from one of the animals that had been fasted for 24 hours. Video of the rumen atrium and reticulum was also collected. The animals recovered uneventfully. Biopsies were subsequently used for extraction and sequencing of mRNA. RESULTS: The ventral surface of the rumen atrium was accessible after 4 hours off pasture, but a larger region was accessible after 24 hours of fasting. Sedation allowed access for endoscope use for around 5 to 10 minutes after which increased saliva flow was noted. Rumen papillae biopsies were easily collected, with samples from a variety of sites collected in the ∼10 minute time window. High quality RNA was obtained for stranded mRNA sequencing. Of the resulting reads, 69–70% mapped uniquely to version 3.1 of the ovine genome, and 48–49% to a known gene. The rumen mRNA profiles were consistent with a previously reported study. CONCLUSIONS: This method for obtaining rumenal tissue was found to be rapid and resulted in no apparent short or long term effects on the animal. High quality RNA was successfully extracted and amplified from the rumen papillae biopsies, indicating that this technique could be used for future gene expression studies. The use of rumen endoscopy could be extended to collection of a variety of rumen and reticulum anatomical measurements and deposition and retrieval of small sensors from the rumen. Rumen endoscopy offers an attractive and cost effective approach to repeated rumen biopsies compared with serial slaughter or use of cannulated animals.
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.