Project description:The objective of our study was to assess the effect of rumen-protected niacin supplementation on the overall transcriptomics profile of liver tissue on growing Angus × Simmental steers and heifers. Consequently, the vasodilatory, detoxifying, and immune suppressor effects of niacin were evaluated in hepatocytes. After a 30-day supplementation period with rumen-protected niacin on normal weaned beef calves, we observed a significant list of benefits at the liver transcriptome level. Several metabolic pathways revealed positive effects of administration of rumen-protected niacin; for example, a decrease in lipolysis, apoptosis, inflammatory responses, atherosclerosis, oxidative stress, fibrosis, and vasodilation-related pathways. Therefore, results from this study could potentially promote supplementation of rumen-protected niacin on beef cattle backgrounding operations or new arrivals to a feedlot, especially during the acclimation period when the health status of growing beef cattle is usually compromised.
Project description:Creatine pyruvate (CrPyr) is a new multifunctional nutrient that can provide both pyruvate and creatine. It has been shown to relieve the heat stress of beef cattle by improving antioxidant activity and rumen microbial protein synthesis, but the mechanism of CrPyr influencing rumen fermentation remains unclear. This study aimed to use metaproteomics technologies to investigate the bacterial protein function in rumen fluid samples taken from heat-stressed beef cattle treated with or without 60 g/d CrPyr.
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.
Project description:Hanwoo cattle are a Korean breed renowned for their cultural significance and high-quality beef, characterized by low cholesterol and high unsaturated fat ratio. Growth is divided into a growing phase focused on development and a fattening phase for marbling. Proper feed management, considering genetic and environmental factors, is vital for maximizing growth potential. The rumen plays a crucial role in digestion and gene expression regulation, with rumen fermentation being central to nutrient absorption and cattle health. In this study, we conduct transcriptome analysis of the rumen at eight timepoints. Our goal is to identify genetic factors that influence the growth of Hanwoo steers to enhance our understanding of the rumen’s functions and roles during their growth. In this RNA-sequencing analysis of Hanwoo steer rumen, differential gene expression was examined over eight timepoints, highlighting significant genetic changes, particularly between 12 and 26 months. Weighted gene co-expression network analysis identified and organized as three modules: turquoise, blue, and yellow. The turquoise module, linked to immune response, showed down-regulation in genes at 30 months. The blue module, associated with steroid metabolism, was notably up-regulated at 26 months. The yellow module’s genes showed a consistent increase in expression with growth. These modules and their functional annotations provide a deeper understanding of the biological processes during Hanwoo growth, highlighting the intricate relationship between gene expression and cattle development. The growth stages of Hanwoo steers were explored in our investigation utilizing rumen transcriptome data. The rumen plays critical role in their development, particularly during the growing and fattening phases. Proper feed management, considering the rumen’s function, is essential for optimal growth. Transcriptome analysis helps identify genes associated with growth and provides insights for cattle breeding and management practices. Understanding the complex connection between gene expression and Hanwoo development is essential for maximizing productivity and health.
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: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: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:<p>Background: Grazing yearly on pasture is a traditional practice for yaks, which cannot meet the requirements of yak products since the insufficient forage supplied in the cold season results in a long production cycle. An intensive feeding system increasing production efficiency has been selected for beef and dairy cattle. However, its impacts on yaks are less studied, and it is unclear how the rumen microbiome, rumen metabolites and the host metabolome respond to an intensive feeding system and contribute to yak growth. Here, multi-omics, including rumen metagenomics, rumen and plasma metabolomics, were performed to classify the effects and regulatory mechanisms of intensive feeding system.</p><p>Results: In our results, increased growth performance and rumen volatile fatty acid (VFA) concentration were observed in yaks under the intensive feeding system compared to yaks grazing on pastures. Metagenomics of the rumen microbiome revealed that species of Clostridium and Methanobrevibacter as well as Piromyces sp. E2 and Anaeromyces robustus were increased in the rumen of intensively fed yaks, interacting and contributing to amino acid and carbohydrate metabolism. The rumen of yaks grazing on pasture had more cellulolytic microbes, such as Bacteroides and Fibrobacter species. Moreover, yaks under the intensive feeding system had lower methanogen and increased methane degradation functions, suggesting that the methane emission of these yaks may be decreased. These abundant microbiomes were correlated with the pathways of “Alanine aspartate and glutamate metabolism” and “Pyruvate metabolism”. Similar with rumen VFA results, metabolomics found that intensively fed yaks had greater concentrations of metabolites related to carbohydrates. The methyl metabolites associated with methane production were greater in the rumen of yak grazing on pasture. Additionally, these changed rumen microbiomes and their metabolites resulted in changes in plasma metabolome, finally affecting yaks’ growth.</p><p>Conclusions: This study compressively classifies the mechanism that an intensive feeding system benefits yak production and reveals the importance of the rumen microbiome for host metabolism and performance. These findings evidence that an intensive feeding system could be used for the yak industry.</p>