Gut-brain communication via the peripheral neural network is vital for regulating local digestive function and systemic physiology.Gut microbiota,which produces a wide array of neuroactive compounds,is a critical modu...Gut-brain communication via the peripheral neural network is vital for regulating local digestive function and systemic physiology.Gut microbiota,which produces a wide array of neuroactive compounds,is a critical modulator in this bidirectional dialog.Perturbations in the gut microbiota have been implicated in neurological disorders such as depression and stress.Distinct from humans and other monogastric animals,ruminants possess a unique,microbially dense gastrointestinal compartment,the rumen,that facilitates the digestion of fibrous plant materials.These ruminal microbes are likely key contributors to rumen-brain crosstalk.Unlike certain microbe-derived neuroactive compounds produced in the hindgut that are minimally absorbed and primarily excreted in feces,those generated in rumen can reach the small intestine,where they are largely absorbed and affect central nervous system through systemic regulation in addition to the vagal pathway.Notably,emerging evidence suggests that rumen microbiota dysbiosis under stress is associated with abnormal behavior,altered hormonal and neurotransmitter levels.In this review,we introduce the concept of the rumen-microbiome-brain axis by comparing the anatomical structures and microbial characteristics of the intestine and the rumen,emphasizing the neuroactive potential of rumen microbiome and underlying mechanisms.Advances in this frontier hold tremendous promise to reveal a novel dimension of the gut-microbiome-brain axis,providing transformative opportunities to improve ruminant welfare,productivity,and agricultural sustainability.展开更多
Background The enteric methane inhibitor 3-nitrooxypropanol(3-NOP)inhibits the key enzyme in ruminal methanogenesis,but whether short-term(ST)and long-term(LT)dietary supplementation has similar effects on rumen micro...Background The enteric methane inhibitor 3-nitrooxypropanol(3-NOP)inhibits the key enzyme in ruminal methanogenesis,but whether short-term(ST)and long-term(LT)dietary supplementation has similar effects on rumen microbiota in beef cattle and how microbes change after 3-NOP withdrawal have not been studied.This study investigated changes in rumen bacteria,archaea,and protozoa after ST and LT dietary supplementation and removal of 3-NOP using metataxonomic analysis.Results A total of 143 rumen samples were collected from two beef cattle studies with 3-NOP supplementation.The ST study(95 samples)used eight ruminally cannulated beef cattle in a 4×4 Latin square design with four 28-d of 3-NOP treatments[mg/kg of dry matter(DM)]:control:0,low:53,med:161,and high:345.The LT study(48 samples)was a completely randomized design with two 3-NOP treatments[control:0,and high:280 mg/kg of DM)fed for 112-d followed by a 16-d withdrawal(without 3-NOP).Bacterial and archaeal communities were significantly affected by 3-NOP supplementation but limited effects on protozoal communities were observed.Under ST supplementation,the relative abundances of Prevotella,Methanobrevibacter(Mbb.)ruminantium,Methanosphaera sp.ISO3-F5,and Entodinium were increased(Q<0.05),whereas those of Mbb.gottschalkii and Epidinium were decreased(Q<0.05)with 3-NOP supplementation.In LT study,relative abundances of Mbb.ruminantium,and Methanosphaera sp.Group5 were increased(Q<0.05),while those of Saccharofermentans and Mbb.gottschalkii were decreased(Q<0.05)with 3-NOP supplementation.Comparison between 3-NOP supplementation and the withdrawal revealed increased relative abundances of Clostridia UCG-014 and Oscillospiraceae NK4A214 group and decreased those of Eubacterium nodatum group and Methanosphaera sp.Group5(P<0.05)after 3-NOP withdrawal.Further comparison of rumen microbiota between control and 3-NOP withdrawal showed significantly higher(P=0.029)relative abundances of Eggerthellaceae DNF00809,p-1088-a5 gut group,and Family XII UCG-001 in control group while no significant differences were detected for archaea and protozoa.Microbial network analysis revealed that microbial interactions differed by both 3-NOP dose and durations.Conclusions Both ST and LT supplementation affected overall rumen microbial profile,with individual microbial groups responded to 3-NOP supplementation differently.After 3-NOP withdrawal,not all microbes showed recovery,indicating that the 3-NOP driven shifts were only partially reversible.These findings provide an understanding of the effects of 3-NOP on rumen microbial communities and their adaptability to methane mitigation strategies.展开更多
Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular ves...Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular vesicles(mEVs)are critical mediators of microbe-host communication.However,the role of mEVs in rumen microbiota-mediated mastitis has not yet been reported.In this study,we used an HCD-induced rumen microbiota dysbiosis model to investigate the role of mEVs-derived from rumen microbiota in the pathogenesis of mastitis.Results Our results indicate that HCD leads to mastitis and systemic inflammation.Meanwhile,HCD-fed goats exhibited substantial rumen microbiota dysbiosis and the disruption of the rumen barrier.Transplanting rumen microbiota from HCD goats into mice induced both mastitis and systemic inflammation in the recipients.Specifically,HCD increases the production of mEVs carrying microbial DNA,which can translocate across the compromised rumen barrier to the mammary gland,triggering a mammary inflammatory response via activation of the cGAS-STING-NF-κB/NLRP3 pathway.Furthermore,treating mice with mEVs isolated from the rumen fluid of HCD goats directly induced mastitis,whereas depletion of microbial DNA attenuated mEVs-induced mastitis.Conclusion Our findings suggest that HCD induces rumen microbiota dysbiosis and impairs rumen barrier function.This dysfunction leads to an increase in microbial DNA-containing mEVs,which subsequently leak into the mammary gland.Once there,these mEVs activate the cGAS-STING-NF-κB/NLRP3 signaling pathway,ultimately inducing mastitis.This study provides a new perspective on the“rumen microbiota-mammary gland axis”and enhances the understanding of the pathogenesis of mastitis.展开更多
Background Methane(CH_(4))emissions from ruminants significantly contribute to greenhouse gas effects and energy loss in livestock production.Methyl-coenzyme M reductase(MCR)is the key enzyme in methanogenesis,making ...Background Methane(CH_(4))emissions from ruminants significantly contribute to greenhouse gas effects and energy loss in livestock production.Methyl-coenzyme M reductase(MCR)is the key enzyme in methanogenesis,making it a promising target for CH_(4) mitigation.This study aimed to identify and validate plant-derived inhibitors by using molecular docking to screen compounds with strong binding affinity to the F430 active site of MCR and assessing their efficacy in reducing CH_(4) emissions.Results Molecular docking analysis identified salvianolic acid C(SAC)as a potent inhibitor of MCR,showing a strong binding affinity to the F430 active site(binding energy:-8.2 kcal/mol).Enzymatic inhibition assays confirmed its inhibitory effect,with a half-maximal inhibitory concentration(IC50)of 692.3μmol/L.In vitro rumen fermentation experiments demonstrated that SAC supplementation(1.5 mg/g DM)significantly reduced CH_(4)production(P<0.01)without negatively affecting major fermentation parameters.Microbial community analysis using 16S rRNA sequencing and metagenomics revealed that SAC selectively altered the rumen microbiota,increasing the relative abundance of Bacteroidota while significantly reducing Methanobrevibacter(P=0.04).Moreover,metagenomic analysis showed the downregulation of key methanogenesis-related genes(mcrA and rnfC),suggesting a dual mechanism involving direct enzymatic inhibition and microbial community modulation.Conclusions These findings indicate that SAC effectively reduces CH_(4)production by inhibiting MCR activity and reshaping the rumen microbial community.As a plant-derived compound with strong inhibitory effects on methanogenesis,SAC presents a promising and sustainable alternative to synthetic CH_(4) inhibitors,offering potential applications for mitigating CH_(4)emissions in livestock production.展开更多
As a major contributor to methane production in agriculture,there is a need for a suitable methane inhibitor to reduce ruminant methane emissions and minimize the impact on the climate.This work aimed to explore the i...As a major contributor to methane production in agriculture,there is a need for a suitable methane inhibitor to reduce ruminant methane emissions and minimize the impact on the climate.This work aimed to explore the influence of cordycepin on rumen fermentation,gas production,microbiome and their metabolites.A total of 0.00,0.08,0.16,0.32,and 0.64 g L^(–1)cordycepin were added into fermentation bottles containing 2 g total mixed ration for in vitro ruminal fermentation,and then the gas produced and fermentation parameters were measured for each bottle.Samples from the 0 and 0.64 g L^(–1)cordycepin addition were selected for 16S rRNA gene sequencing and metabolome analysis.The result of this experiment indicated that the addition of cordycepin could linearly increase the concentration of total volatile fatty acid,ammonia nitrogen,the proportion of propionate,valerate,and isovalerate,and linearly reduce ruminal pH and methane,carbon dioxide,hydrogen and total gas production,as well as the methane proportion,carbon dioxide proportion and proportion of butyrate.In addition,there was a quadratic relationship between hydrogen and cordycepin addition.At the same time,the relative abundance of Succiniclasticum,Prevotella,Rikenellaceae_RC9_gut_group,NK4A214_group,Christensenellaceae_R_(7)_group,unclassified_F082,Veillonellaceae_UCG_001,Dasytricha,Ophryoscolex,Isotricha,unclassified_Eukaryota,Methanobrevibacter,and Piromyces decreased significantly after adding the maximum dose of cordycepin.In contrast,the relative abundance of Succinivibrio,unclassified_Succinivibrionaceae,Prevotellaceae_UCG_001,unclassified_Lachnospiraceae,Lachnospira,Succinivibrionaceae_UCG_002,Pseudobutyrivibrio,Entodinium,Polyplastron,unclassified_Methanomethylophilaceae,Methanosphaera,and Candidatus_Methanomethylophilus increased significantly.Metabolic pathways such as biosynthesis of unsaturated fatty acids and purine metabolism and metabolites such as arachidonic acid,adenine,and 2′-deoxyguanosine were also affected by the addition of cordycepin.Based on this,we conclude that cordycepin is an effective methane emission inhibitor that can change the rumen metabolites and fermentation parameters by influencing the rumen microbiome,thus regulating rumen methane production.This experiment may provide a potential theoretical reference for developing Cordyceps byproduct or additives containing cordycepin as methane inhibitors.展开更多
Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the envi...Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats,and to watercourses contributing to aquatic eutrophication.While there is much evidence that NUE can be improved by reducing the crude protein(CP)content of dairy cow diets,the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.This study examined the effects of reducing the CP contents of dairy cow diets on cow performance,NUE,the relationship between NUE and residual feed intake(RFI),and the rumen microbiome.Results Dietary CP content did not affect feed intake,milk yield or milk composition(P>0.05),except for milk urea N(MUN),which increased with increasing diet CP content(P<0.05).The mean NUE was 34%,34%and 31%for the LCP(low-protein,15%),MCP(medium-protein,16%),and HCP(high-protein,17%)diets,respectively.RFI was negatively correlated with NUE(r=−0.57,P<0.001).The rumen ammonia-N concentrations increased with increasing dietary CP;however,the ruminal pH and volatile fatty acid(VFA)content of the rumen fluid remained constant.Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.Reducing dietary CP content in dairy cow diets did not affect microbial composition,diversity and functional profiles.The family Bacteroidaceae was more abundant in HE(high-efficiency)cows,whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE(low-efficiency)cows.Additionally,propanoate metabolism,cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows,whilst the methane(CH4)metabolism pathway was upregulated in LE cows.Conclusions The results demonstrate that diet CP can be reduced with no loss in cow performance,but with an associated reduction in N excretion.The abundance of microbial populations differed between low and high efficiency cows,which may contribute to the differences in efficiency observed.展开更多
Yaks are well-adapted to the harsh environment of the Tibetan Plateau,and they emit less enteric methane(CH_(4))and digest poor-quality forage better than cattle.To examine the potential of yak rumen inoculum to mitig...Yaks are well-adapted to the harsh environment of the Tibetan Plateau,and they emit less enteric methane(CH_(4))and digest poor-quality forage better than cattle.To examine the potential of yak rumen inoculum to mitigate CH_(4)production and improve digestibility in cattle,we incubated substrate with rumen inoculum from yak(YRI)and cattle(CRI)in vitro in five ratios(YRI:CRI):(1)0:100(control),(2)25:75,(3)50:50,(4)75:25 and(5)100:0 for 72 h.The YRI:CRI ratios of 50:50,75:25 and 100:0 produced less total gas and CH_(4)and accumulated less hydrogen(H_(2))than0:100(control)at most time points.From 12 h onwards,there was a linear decrease(P<0.05)in carbon dioxide(CO_(2))production with increasing YRI:CRI ratio.At 72 h,the ratios of 50:50 and 75:25 had higher dry matter(+7.71%and+4.11%,respectively),as well as higher acid detergent fiber digestibility(+15.5%and+7.61%,respectively),when compared to the 0:100 ratio(P<0.05).Increasing the proportion of YRI generally increased total VFA concentrations,and,concomitantly,decreased the proportion of metabolic hydrogen([2H])incorporated into CH_(4),and decreased the recovery of[2H].The lower[2H]recovery indicates unknown[2H]sinks in the culture.Estimated Gibbs free energy changes(ΔG)for reductive acetogenesis were negative,indicating the thermodynamic feasibility of this process.It would be beneficial to identify:1)the alternative[2H]sinks,which could help mitigate CH_(4)emission,and 2)core microbes involved in fiber digestion.This experiment supported lower CH_(4)emission and greater nutrient digestibility of yaks compared to cattle.Multi-omics combined with microbial culture technologies developed in recent years could help to better understand fermentation differences among species.展开更多
Background In this study,the effects of L-leucine(Leu)on rumen fermentation parameters,rumen epithelium development,amino acid composition,rumen bacterial communities and rumen metabolites in beef cattle were investig...Background In this study,the effects of L-leucine(Leu)on rumen fermentation parameters,rumen epithelium development,amino acid composition,rumen bacterial communities and rumen metabolites in beef cattle were investigated.Twenty-four fattening Angus females of similar initial weight(575.5±22.1 kg)were randomly assigned to 2 treatments with 4 replicate pens(3 cattle per pen).They were fed either a basal diet or a basal diet supplemented with 6.0 g L-Leu/100 kg BW/d for 120 d.Results(1)Leu increased the ruminal concentrations of total volatile fatty acid(VFA)(P=0.017),propionate(P=0.023),isovalerate(P=0.001),and branched-chain volatile fatty acid(BCVFA)(P=0.01)at 4 h post-feeding.It also tended to increase acetate(P=0.083)and decrease the ammonia-N(NH_3-N)concentration(P=0.055),but it did not affect ruminal pH(P>0.1).Leu also increased microbial crude protein(MCP)(P=0.026)at 4 h post-feeding,but decreased MCP at 8 h post-feeding(P=0.010).(2)Supplementation with L-Leu increased the ruminal concentrations of phenylalanine(P=0.011),lysine(P=0.034),and tyrosine(P=0.033),while decreasing the cystine concentration(P=0.010).(3)Leu increased the thickness of the stratum spinosum and basal(P<0.05),while decreasing the thickness of the stratum granulosum(P<0.05).(4)Leu upregulated the relative mRNA abundance of genes involved in tight junction proteins(P<0.05)and VFA absorption and metabolism(P<0.01)in the rumen epithelium.This upregulation was positively correlated with the concentrations ruminal isovalerate and BCVFA(P<0.01).(5)L-Leu did not affect the diversity and richness of ruminal microbes(P>0.05),but differential bacterial biomarkers(LEfSe,LDA>2)were either positively or negatively correlated with ruminal MCP,NH_3-N,and BCVFA concentrations(P<0.001).Additionally,differential bacterial metabolites(OPLS-DA,VIP>1.5)were primarily enriched in the amino acid metabolism pathway and the cofactors and vitamins metabolism pathway(P<0.05).Conclusions Dietary supplementation with L-Leu altered rumen fermentation parameters and patterns,improved rumen epithelial morphology,and enhanced the expression of genes related to VFA absorption and metabolism in the rumen epithelium of beef cattle.展开更多
Epigenetic regulation in the rumen,a unique ruminant organ,remains largely unexplored compared with other tissues studied in model species.In this study,we perform an in-depth analysis of the epigenetic and transcript...Epigenetic regulation in the rumen,a unique ruminant organ,remains largely unexplored compared with other tissues studied in model species.In this study,we perform an in-depth analysis of the epigenetic and transcriptional landscapes across fetal and adult bovine tissues as well as pluripotent stem cells.Among the extensive methylation differences across various stages and tissues,we identify tissue-specific differentially methylated regions(tsDMRs)unique to the rumen,which are crucial for regulating epithelial development and energy metabolism.These tsDMRs cluster within super-enhancer regions that overlap with transcription factor(TF)binding sites.Regression models indicate that DNA methylation,along with H3K27me3 and H3K27ac,can be used to predict enhancer activity.Key upstream TFs,including SOX2,FOSL1/2,and SMAD2/3,primarily maintain an inhibitory state through bivalent modifications during fetal development.Downstream functional genes are maintained mainly in a stable repressive state via DNA methylation until differentiation is complete.Our study underscores the critical role of tsDMRs in regulating distal components of rumen morphology and function,providing key insights into the epigenetic regulatory mechanisms that may influence bovine production traits.展开更多
Background As an indigenous livestock species on the Tibetan Plateau,Tibetan sheep exhibit remarkable adaptability to low temperatures and nutrient-scarce environments.During the cold season,Tibetan sheep are typicall...Background As an indigenous livestock species on the Tibetan Plateau,Tibetan sheep exhibit remarkable adaptability to low temperatures and nutrient-scarce environments.During the cold season,Tibetan sheep are typically managed under two feeding regimes:barn feeding(BF)and traditional grazing(TG).However,the molecular mechanisms underlying their adaptation to these distinct management strategies remain unclear.This study aimed to investigate the adaptive strategies of rumen function in Tibetan sheep to cold-season feeding regimes by integrating analyses of rumen morphology,microbiome,metabolome,and transcriptome.Twelve healthy Tibetan sheep with similar body weights were assigned into two groups(BF vs.TG).At the end of the experiment,rumen tissues were subjected to histological observation.Multi-omics techniques were employed to evaluate the effects of cold-season feeding regimes on rumen function in Tibetan sheep.Results The ruminal papilla height,width,and muscular thickness were significantly higher in BF group.The relative abundances of Actinobacteria and Succiniclasticum were significantly elevated in the rumen of BF group,whereas Rikenellaceae,Gracilibacteria,and Lachnospiraceae showed higher abundances in the TG group.Metabolomic analysis identified 19 differential metabolites between the two groups,including upregulated compounds in BF group(fumaric acid,maltose,L-phenylalanine,and L-alanine)and TG group(e.g.,phenylacetic acid,salicyluric acid and ferulic acid).These metabolites were predominantly enriched in phenylalanine metabolism,alanine,aspartate and glutamate metabolism,and phenylalanine,tyrosine and tryptophan biosynthesis pathways.Additionally,210 differentially expressed genes(DEGs)were identified in rumen epithelium:100 upregulated DEGs in the BF group were enriched in nutrient metabolism-related pathways(e.g.,fatty acid degradation and PPAR signaling pathway),while 110 upregulated DEGs in the TG group were associated with immune-related pathways(e.g.,p53 signaling pathway and glutathione metabolism).Conclusions Among these,we observed distinct rumen functional responses to different cold-season feeding regimes in Tibetan sheep and revealed energy allocation strategies mediated by host-microbe interactions.In the BF group,Tibetan sheep adopted a"metabolic efficiency-priority"strategy,driving rumen microbiota to maximize energy capture from high-nutrient diets to support host growth.In contrast,the TG group exhibited an"environmental adaptation-priority"strategy,where rumen microbiota prioritized cellulose degradation and anti-inflammatory functions,reallocating energy toward homeostasis maintenance at the expense of rumen development and growth performance.展开更多
Background Rumen microorganisms are key regulators of ruminant growth and production performance.Identifying probiotic candidates through microbial culturomics presents a promising strategy for improving ruminant prod...Background Rumen microorganisms are key regulators of ruminant growth and production performance.Identifying probiotic candidates through microbial culturomics presents a promising strategy for improving ruminant production performance.Our previous study identified significant differences in rumen microbial communities of Holstein calves with varying average daily gain(ADG).This study aims to identify a target strain based on the findings from multi-omics analysis and literature review,isolating and evaluating the target microbial strains from both the rumen and hindgut contents for their probiotic potential.Results Parabacteroides distasonis,a strain closely associated with ADG,was successfully isolated from calf rumen content cultured with Fastidious Anaerobe Agar(FAA)medium and named Parabacteroides distasonis F4.Wholegenome sequencing and pan-genome analysis showed that P.distasonis F4 possesses a core functional potential for carbohydrate and amino acid metabolism,with the ability to produce propionate,acetate,and lactate.The results of targeted and untargeted metabolomics further validated the organic acid production and metabolic pathways of P.distasonis F4.An in vitro simulated rumen fermentation test showed that supplementation with P.distasonis F4 significantly altered rumen microbial community structure and increased the molar proportions of propionate and butyrate in the rumen.Furthermore,an in vivo study demonstrated that dietary supplementation with P.distasonis F4 significantly increased the ADG of pre-weaning calves.Conclusions This study represents the first isolation of P.distasonis F4 from rumen,highlighting its potential as a probiotic strain for improving rumen development and growth performance in ruminants.展开更多
Background Using yeast culture as additives in ruminant feed prevents rumen microbial dysbiosis,enhances performance,and regulates rumen pH.The yeast culture used in this study was developed in-house,and has been show...Background Using yeast culture as additives in ruminant feed prevents rumen microbial dysbiosis,enhances performance,and regulates rumen pH.The yeast culture used in this study was developed in-house,and has been shown to promote rumen epithelial growth in several sheep trials.Changes in protein expression associated with the promotion of rumen epithelial development following the addition of yeast culture,along with the associated molecular mechanisms,remain unknown.We used 2045-day-old weaned lambs to investigate the specific proteins and molecular mechanisms involved in these processes.Half of the lambs were fed yeast culture,and the other half were used as controls.Results Yeast culture enhanced growth performance,facilitated rumen fermentation,and promoted rumen papilla development in weaned lambs.Proteomics data identified 4,831 proteins in the rumen epithelial tissue of lambs,comprising 87 upregulated and 425 downregulated proteins.Administration of yeast culture activated multiple molecular functions within rumen epithelial cells,including oxidative phosphorylation,glutathione metabolism,apoptosis,cell cycle,and vitamin digestion and absorption.The expression of proteins associated with cell cycle regulation increased,whereas those associated with apoptosis decreased.Administration of yeast culture also reduced the duration of the G0/G1 phase of rumen epithelial cells and accelerated the cell cycle.Furthermore,yeast culture showed increased cyclin D1,cyclin-dependent kinase(CDK)2,CDK4,CDK6,and cyclin E1 expressions and decreased cytochrome C(Cyto-c),Bcl-2-related X protein(Bax),cleaved caspase 3(C-caspase 3),caspase 3,and cleaved caspase 7(C-caspase 7)protein expressions.Yeast culture upregulated the insulin-like growth factor-1 receptor(IGF-1R)and insulin-like growth factor-binding protein 5(IGFBP-5)mRNA expressions in rumen epithelial cells.Conclusions Yeast culture facilitates rumen epithelial development by regulating the cell cycle and IGF-1 signaling and reducing the expression of proteins associated with apoptosis in rumen epithelial cells.The findings of this study provide novel insights into the molecular mechanisms through which yeast culture promotes rumen epithelial development in weaned lambs.展开更多
The aim of this study was to investigate the effects of dietary fat on energy and nitrogen(N)metabolism efficiency,rumen fermentation,and microbiota in twin suckling lambs.Thirty pairs of twin male lambs were randomly...The aim of this study was to investigate the effects of dietary fat on energy and nitrogen(N)metabolism efficiency,rumen fermentation,and microbiota in twin suckling lambs.Thirty pairs of twin male lambs were randomly divided into two groups with one group receiving a high-fat diet(HF)and the other a normal-fat diet(NF).Two diets(milk replacer and starter)of equal protein and different fat levels.The metabolism test was conducted when the lambs were 50-60 days old,and nine pairs of twin lambs were randomly selected for slaughter to collect rumen fluid at 60 days old.The result showed that fat addition increased the final body weight(BW),ruminal ammonia nitrogen(NH_(3)-N)content,proportion of propionic acid,and estimated methane production(CH_(4e))(P<0.05).The high fat diet tended to improve digestive energy(DE),metabolism energy(ME),DE/ME,utilisation of N(0.05<P<0.1).However,microbial crude protein(MCP)content,total volatile fatty acids(VFA),acetic acid ratio,and the ratio of acetate to propionate(A:P)were lower than that in the NF group(P<0.05).Regardless of whether fat is added or not,no different were observed in blood metabolites between the treatment.High-throughput sequencing revealed that fat addition before weaning increased phyla Proteobacteria and genera of Succinivibrio,but decreased the relative abundance of Clostridium IV,Dialister,Roseburia,Acidaminococcus,and Megasphaera genera.These findings indicated that high fat diet improved body weight,energy and nitrogen utilization may by shifting the rumen toward propionate fermentation via the enrichment of Succinivibrio.展开更多
Background The environmental impact of feedlot operations is a growing concern,as cattle excrete a significant portion of feed nutrients as waste.Exogenous feed enzymes(EFE)have gained interest for their potential to ...Background The environmental impact of feedlot operations is a growing concern,as cattle excrete a significant portion of feed nutrients as waste.Exogenous feed enzymes(EFE)have gained interest for their potential to enhance feed efficiency in ruminants by improving nutrient digestion.However,EFE effects on ruminal parameters have shown inconsistencies,with limited research on nitrogen metabolism and rumen microbiome impacts.Moreover,the synergistic effects of combining different EFEs remain unclear.This study aimed to evaluate the effects of individual and combined EFE products in feedlot diets on ruminal fermentation parameters,nitrogen metabolism,and ruminal microbial communities.Ten rumen-cannulated Nellore steers[543±28.6 kg of body weight(BW)]were distributed in a replicated Latin-square design(5×5)in individual pens.Treatments included:control(CON,no EFE supplementation),amylase[AML,0.5 g/kg of diet dry matter(DM)],xylanase(FBL,0.9 g/kg DM),half dose combination(HD,0.25 g of AML+0.45 g of FBL/kg of DM),and full dose combination(FD,0.5 g of AML+0.90 g of FBL/kg of DM).The experimental period lasted 19 d and included total urine and feces collection(d 15 to 18)and rumen fluid sampling(d 19)at 0,4,8,12,and 16 h post-feeding for ammonia,volatile fatty acids(VFA),pH and microbiome analysis.Results EFE supplemented animals exhibited lower ruminal ammonia concentrations(P=0.040),and higher acetate proportions(P<0.001)compared to the control group.EFE supplementation resulted in reduced nitrogen(N)excretion in feces(P=0.049)and urine(P=0.036),contributing to improved N retention and efficiency(P=0.045).Additionally,EFE products induced shifts in various microbial taxa at family and genera levels(P≤0.10),which may be associated with the changes observed in ruminal fermentation.Conclusions Our findings demonstrate that EFE supplementation enhances nitrogen retention,reduces ruminal ammonia,and alters ruminal fermentation profiles and microbial populations in feedlot cattle.While the expected synergism between amylase and xylanase did not significantly impact rumen fermentation parameters,it did induce shifts in the rumen microbiome.These results suggest that EFE supplementation may be a promising strategy for improving nutrient utilization and potentially reducing the environmental impact of feedlot operations.展开更多
[Objective]The paper was to investigate the effects of substituting corn pellets with potato residue on the growth performance,rumen fermentation indicators and economic benefits of Xinjiang Brown cattle.[Method]A tot...[Objective]The paper was to investigate the effects of substituting corn pellets with potato residue on the growth performance,rumen fermentation indicators and economic benefits of Xinjiang Brown cattle.[Method]A total of 80 Xinjiang Brown cattle,each 22 months old and with a similar body weight of(250±15)kg,were randomly assigned to four groups,with 20 cattle in each group,utilizing a single-factor experimental design.The total mixed diets for the experimental groups Ⅰ,Ⅱ,and Ⅲ were formulated by substituting corn pellets with 2.00%,4.00%,and 6.00%potato residue,respectively,while the diet in the control group was not substituted with potato residue.The duration of the test was 100 d,which comprised a pre-test period of 10 d and a formal test period of 90 d.During the test period,the average dry matter intake,average daily weight gain and feed-gain ratio were assessed at 30-day intervals,and body size indicators were measured on days 0 and 90.Rumen fluid samples were collected from the oral cavity on days 0,30,60,and 90 to assess rumen fermentation parameters.Additionally,jugular blood samples were obtained during the fasting period,and serum was separated for the analysis of total protein mass concentration,urea nitrogen,and glucose concentration.Furthermore,the economic benefits accrued during the test period were calculated.[Result]The dry matter intake in experimental group Ⅰ was significantly higher than that in the control group from days 31 to 60(P<0.05).In contrast,the differences in dry matter intake between experimental groups Ⅱ and Ⅲ and the control group were not statistically significant(P>0.05).From days 61 to 90,the dry matter intake in experimental group Ⅰ remained significantly higher than that in the other groups(P<0.05).Throughout the entire experimental period,the average daily weight gain observed in experimental group Ⅰ was significantly greater than that recorded in the other groups(P<0.05).Additionally,the total weight gain over the entire period was significantly higher than that of experimental group Ⅱ(P<0.05)and markedly higher than that of both the control group and experimental group Ⅲ(P<0.01).The feed-gain ratio in experimental group Ⅰ was significantly lower than that in experimental group Ⅱ(P<0.05).There were no statisticaly significant differences observed in body height,slope length,thoracic circumference,abdominal circumference,rumen pH,acetic acid,propionic acid,butyric acid,valeric acid,total volatile fatty acids,and ammoniacal nitrogen mass concentration among the groups(P>0.05).On the 90th day of the experiment,the serum urea nitrogen concentration in beef cattle from experimental groups Ⅰ and Ⅱ was significantly lower than that in the control group and experimental group Ⅲ(P<0.05).Additionally,the profit margins in experimental groups Ⅰ,Ⅱ,and Ⅲ were higher than those in the control group,and the profit margin in experimental group Ⅰ was the highest.[Conclusion]The substitution of corn pellets with potato residue has the potential to enhance the average daily weight gain and total weight gain throughout the entire period in beef cattle,while simultaneously reducing the feed-gain ratio.However,this substitution does not appear to have a significant impact on body size indicators,rumen fermentation parameters,or the concentrations of serum total protein and glucose in beef cattle.Furthermore,this approach may yield improved breeding profitability,with a recommended substitution ratio of 2.00%based on the conditions of this experiment.展开更多
Background Subacute rumen acidosis(SARA)is a common metabolic disorder in ruminants that disrupts the rumen microbiome and animal health,but diagnosis is challenging due to subtle symptoms and invasive testing require...Background Subacute rumen acidosis(SARA)is a common metabolic disorder in ruminants that disrupts the rumen microbiome and animal health,but diagnosis is challenging due to subtle symptoms and invasive testing require-ments.This study explores the potential of the buccal(oral)microbiome as a diagnostic indicator for SARA,hypoth-esizing an interaction with the rumen microbiome.Results The study involved 47 dairy goats,including 11 on a control diet and 36 on high-concentrate diets with increasing rumen-degradable starch.Animals were grouped based on dietary exposure and ruminal pH:Control,Low-RDS Tolerance/SARA(LRDST/LRDSS),and High-RDS Tolerance/SARA(HRDST/HRDSS).Transcriptomics of rumen epithelium showed heightened inflammatory pathway gene expression in SARA-susceptible goats compared to controls and tolerant groups.Alpha diversity of ruminal bacteria showed lower Shannon diversity in HRDSS goats compared to HRDST whereas buccal bacteria displayed significantly lower Chao1 diversity in LRDSS goats compared to HRDST.Beta diversity analyses revealed distinct patterns between SARA-affected goats and healthy controls in both ruminal and buccal microbiomes.Prevotellaceae_UCG-003 emerged as a candidate biomarker,with reduced abundance in SARA-susceptible goats in both rumen and buccal samples.Machine learning classifiers achieved high accuracy in distinguishing SARA-susceptible goats using this genus(rumen AUC=0.807;buccal AUC=0.779).Source tracking analysis illustrated diminished cross-population of bacteria from the buccal to rumen(2.86%to 0.25%)and vice versa(8.59%to 1.17%),signifying compromised microbial interchange in SARA-affected goats.A microbiota transplant experiment verified SARA microbiota’s ability to induce pH decline,escalate inflammation-related gene expression(MAPK10,IL17B,FOSB,SPP1),disrupt microbial transfer,and reduce Prevotellaceae_UCG-003 in recipients.Conclusion Our findings highlight SARA’s dual impact on ruminal and buccal microbiota,exacerbating epithelial inflammation gene expression.Shifts in the buccal microbiome,specifically reductions in Prevotellaceae_UCG-003,mirror ruminal changes and can be influenced by inter-compartmental bacterial transmission,thereby offering a non-invasive diagnostic approach for SARA.展开更多
Background During the transition period,excessive negative energy balance(NEB)lead to metabolic disorders and reduced milk yield.Rumen microbes are responsible for resolving plant material and producing volatile fatty...Background During the transition period,excessive negative energy balance(NEB)lead to metabolic disorders and reduced milk yield.Rumen microbes are responsible for resolving plant material and producing volatile fatty acids(VFA),which are the primary energy source for cows.In this study,we aimed to investigate the effect of citrus peel extract(CPE)supplementation on rumen microbiota composition,energy metabolism and milk performance of peri-partum dairy cows.Methods Dairy cows were fed either a basal diet(CON group)or the same basal diet supplemented with CPE via intragastric administration(4 g/d,CPE group)for 6 weeks(3 weeks before and 3 weeks after calving;n=15 per group).Samples of serum,milk,rumen fluid,adipose tissue,and liver were collected to assess the effects of CPE on rumen microbiota composition,rumen fermentation parameters,milk performance,and energy metabolic status of dairy cows.Results CPE supplementation led to an increase in milk yield,milk protein and lactose contents,and serum glucose levels,while reduced serum concentrations of non-esterified fatty acid,β-hydroxybutyric acid,insulin,aspartate aminotransferase,alanine aminotransferase,and haptoglobin during the first month of lactation.CPE supplemen-tation also increased the content of ruminal VFA.Compared to the CON group,the abundance of Prevotellaceae,Methanobacteriaceae,Bacteroidales_RF16_group,and Selenomonadaceae was found increased,while the abun-dance of Oscillospiraceae,F082,Ruminococcaceae,Christensenellaceae,Muribaculaceae UCG-011,Saccharimona-daceae,Hungateiclostridiaceae,and Spirochaetaceae in the CPE group was found decreased.In adipose tissue,CPE supplementation decreased lipolysis,and inflammatory response,while increased insulin sensitivity.In the liver,CPE supplementation decreased lipid accumulation,increased insulin sensitivity,and upregulated expression of genes involved in gluconeogenesis.Conclusions Our findings suggest that CPE supplementation during the peripartum period altered rumen micro-biota composition and increased ruminal VFA contents,which further improved NEB and lactation performance,alleviated lipolysis and inflammatory response in adipose tissue,reduced lipid accumulation and promoted gluconeo-genesis in liver.Thus,CPE might contribute to improve energy metabolism and consequently lactation performance of dairy cows during the transition period.展开更多
Background Insect meals have been identified as innovative and sustainable feedstuffs that could be used in ruminant nutrition.However,current research on the effects that their processing may have on rumen digestibil...Background Insect meals have been identified as innovative and sustainable feedstuffs that could be used in ruminant nutrition.However,current research on the effects that their processing may have on rumen digestibility and fatty acid(FA)biohydrogenation is scant.This trial aims to investigate the effects(i)of drying temperature of fullfat Hermetia illucens(HI)and Tenebrio molitor(TM)meals,and(ii)of residual ether extract(EE)content of defatted HI and TM meals,on their fermentation characteristics and FA of rumen digesta after 24-h in vitro rumen incubation.Methods The tested full-fat meals included four HI and four TM meals obtained applying drying temperatures ranging from 30℃ to 70℃,while the tested defatted meals consisted of five HI and two TM meals containing a residual EE content ranging from 4.7 to 19.7 g EE/100 g dry matter(DM).The applied statistical models(GLM ANOVA)tested the effects of insect species,drying temperature(full-fat meals)or EE content(defatted meals),and their interaction.Results Drying temperature had minor effects on in vitro ruminal digestibility and FA profile of rumen digesta.Irrespective of insect species,increasing the drying temperature led to a reduction of in vitro degradation of proteins from insect meals,as outlined by the significant decrease in ammonia production(-0.009 mmol/g DM and-0.126 g/100 g total N for each additional 1℃).Irrespective of insect species,defatting increased total gas,volatile fatty acids(VFA)and CH_(4) productions,and the proportions of total saturated and branched-chain FA in rumen digesta(+0.038 mmol/g DM,+0.063 mmol/g DM,+12.9μmol/g DM,+0.18 g/100 g FA,and+0.19 g/100 g FA for each reduced 1 g EE/100 g DM,respectively),and reduced the proportion of total PUFA(-0.12 g/100 g FA).Conclusions The applied drying temperatures of full-fat insect meals are too low to exert impactful effects on rumen digestibility and FA biohydrogenation.Fat lowered fermentation activity,probably because of an inhibitory effect on rumen microbiota.The increased ruminal digestibility of defatted insect meals suggests that they can be more suitable to be used in ruminant nutrition than full-fat ones.展开更多
[Objective] The aim of this study is to understand the population composition of methanogens in rumen fluid of grazing Inner Mongolian cashmere goat. [Method] Total DNAs of various bacteria in rumen fluid were isolate...[Objective] The aim of this study is to understand the population composition of methanogens in rumen fluid of grazing Inner Mongolian cashmere goat. [Method] Total DNAs of various bacteria in rumen fluid were isolated for PCR amplification using the specifically designed primers based on conservative mcrA sequence of methanogens; then mcrA specific clone library was accordingly established. The restriction fragment length polymorphism(RFLP) of the library was further analyzed by digestion of restriction enzyme Taq I. [Result] One hundred and five randomly selected specific colonies were classified into six RFLP types, among which the dominant type accounts for 38%, and other types account for 27%, 18%, 5.5% and 4.5%, respectively. [Conclusion] There are at least six different methanogens in rumen fluid of grazing Inner Mongolian cashmere goat.展开更多
[Objective]The paper was to provide reference for further study and development of gayal（Bos frontalis）.[Method]According to the research status at home and abroad,the biological characteristics and rumen microorgan...[Objective]The paper was to provide reference for further study and development of gayal（Bos frontalis）.[Method]According to the research status at home and abroad,the biological characteristics and rumen microorganisms of gayal in Yunnan Province was studied.[Result]Gayal in Yunnan had typical body form and very good meat production performance,its muscle fiber diameter was significantly less than other kinds of cattle;the water holding ratio,muscle tenderness and muscle succulency were significantly higher than others;its amount,shape and structure of chromosome were different from yellow cattle（Bos taurus）and wild cattle（Bos gaurus）,and the amounts of those chromosomes（2n）were 58,60 and 56,respectively.It could create hybrid with yellow cattle;the gayal＇s special diet was bamboo,its in vitro dry matter digestibility（IVDMD）on various crude forage was significantly higher than yellow cattle in Yunnan;the viable bacteria and cellulolytic bacteria in rumen were 4.51×109 and 1.63×109 CFU/ml,which was significantly higher than yellow cattle in Yunnan,its dominant bacteria in rumen mainly was cellulolytic bacteria.[Conclusion]Gayal not only had high academic value,but also had a great development value.展开更多
基金supported by National Institute of Food and Agriculture,U.S.Department of Agriculture,under the award number 2024-67015-42622 to PFMississippi State Agricultural and Forestry Experiment Station(MAFES)Strategic Research Initiative Programsupported by the Mississippi State University College of Agriculture and Life Science/MAFES Undergraduate Research Scholars Program。
文摘Gut-brain communication via the peripheral neural network is vital for regulating local digestive function and systemic physiology.Gut microbiota,which produces a wide array of neuroactive compounds,is a critical modulator in this bidirectional dialog.Perturbations in the gut microbiota have been implicated in neurological disorders such as depression and stress.Distinct from humans and other monogastric animals,ruminants possess a unique,microbially dense gastrointestinal compartment,the rumen,that facilitates the digestion of fibrous plant materials.These ruminal microbes are likely key contributors to rumen-brain crosstalk.Unlike certain microbe-derived neuroactive compounds produced in the hindgut that are minimally absorbed and primarily excreted in feces,those generated in rumen can reach the small intestine,where they are largely absorbed and affect central nervous system through systemic regulation in addition to the vagal pathway.Notably,emerging evidence suggests that rumen microbiota dysbiosis under stress is associated with abnormal behavior,altered hormonal and neurotransmitter levels.In this review,we introduce the concept of the rumen-microbiome-brain axis by comparing the anatomical structures and microbial characteristics of the intestine and the rumen,emphasizing the neuroactive potential of rumen microbiome and underlying mechanisms.Advances in this frontier hold tremendous promise to reveal a novel dimension of the gut-microbiome-brain axis,providing transformative opportunities to improve ruminant welfare,productivity,and agricultural sustainability.
基金funded by the Beef Cattle Research Council Cluster(FDE.18.21C)Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery,NSERC Canadian Research Chair(Tier 1)program+2 种基金NSERC Alliance program(ALLRP 588541‐23)Foundation for Food&Agriculture Research Greener Cattle Initiative(Award ID 22‐000373)DSM Nutritional Products,Kaiseraugst,Switzerland。
文摘Background The enteric methane inhibitor 3-nitrooxypropanol(3-NOP)inhibits the key enzyme in ruminal methanogenesis,but whether short-term(ST)and long-term(LT)dietary supplementation has similar effects on rumen microbiota in beef cattle and how microbes change after 3-NOP withdrawal have not been studied.This study investigated changes in rumen bacteria,archaea,and protozoa after ST and LT dietary supplementation and removal of 3-NOP using metataxonomic analysis.Results A total of 143 rumen samples were collected from two beef cattle studies with 3-NOP supplementation.The ST study(95 samples)used eight ruminally cannulated beef cattle in a 4×4 Latin square design with four 28-d of 3-NOP treatments[mg/kg of dry matter(DM)]:control:0,low:53,med:161,and high:345.The LT study(48 samples)was a completely randomized design with two 3-NOP treatments[control:0,and high:280 mg/kg of DM)fed for 112-d followed by a 16-d withdrawal(without 3-NOP).Bacterial and archaeal communities were significantly affected by 3-NOP supplementation but limited effects on protozoal communities were observed.Under ST supplementation,the relative abundances of Prevotella,Methanobrevibacter(Mbb.)ruminantium,Methanosphaera sp.ISO3-F5,and Entodinium were increased(Q<0.05),whereas those of Mbb.gottschalkii and Epidinium were decreased(Q<0.05)with 3-NOP supplementation.In LT study,relative abundances of Mbb.ruminantium,and Methanosphaera sp.Group5 were increased(Q<0.05),while those of Saccharofermentans and Mbb.gottschalkii were decreased(Q<0.05)with 3-NOP supplementation.Comparison between 3-NOP supplementation and the withdrawal revealed increased relative abundances of Clostridia UCG-014 and Oscillospiraceae NK4A214 group and decreased those of Eubacterium nodatum group and Methanosphaera sp.Group5(P<0.05)after 3-NOP withdrawal.Further comparison of rumen microbiota between control and 3-NOP withdrawal showed significantly higher(P=0.029)relative abundances of Eggerthellaceae DNF00809,p-1088-a5 gut group,and Family XII UCG-001 in control group while no significant differences were detected for archaea and protozoa.Microbial network analysis revealed that microbial interactions differed by both 3-NOP dose and durations.Conclusions Both ST and LT supplementation affected overall rumen microbial profile,with individual microbial groups responded to 3-NOP supplementation differently.After 3-NOP withdrawal,not all microbes showed recovery,indicating that the 3-NOP driven shifts were only partially reversible.These findings provide an understanding of the effects of 3-NOP on rumen microbial communities and their adaptability to methane mitigation strategies.
基金supported by the National Natural Science Foundation of China(32330105 and 32301247)National Key R&D Program of China(2023YFD1801100)。
文摘Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular vesicles(mEVs)are critical mediators of microbe-host communication.However,the role of mEVs in rumen microbiota-mediated mastitis has not yet been reported.In this study,we used an HCD-induced rumen microbiota dysbiosis model to investigate the role of mEVs-derived from rumen microbiota in the pathogenesis of mastitis.Results Our results indicate that HCD leads to mastitis and systemic inflammation.Meanwhile,HCD-fed goats exhibited substantial rumen microbiota dysbiosis and the disruption of the rumen barrier.Transplanting rumen microbiota from HCD goats into mice induced both mastitis and systemic inflammation in the recipients.Specifically,HCD increases the production of mEVs carrying microbial DNA,which can translocate across the compromised rumen barrier to the mammary gland,triggering a mammary inflammatory response via activation of the cGAS-STING-NF-κB/NLRP3 pathway.Furthermore,treating mice with mEVs isolated from the rumen fluid of HCD goats directly induced mastitis,whereas depletion of microbial DNA attenuated mEVs-induced mastitis.Conclusion Our findings suggest that HCD induces rumen microbiota dysbiosis and impairs rumen barrier function.This dysfunction leads to an increase in microbial DNA-containing mEVs,which subsequently leak into the mammary gland.Once there,these mEVs activate the cGAS-STING-NF-κB/NLRP3 signaling pathway,ultimately inducing mastitis.This study provides a new perspective on the“rumen microbiota-mammary gland axis”and enhances the understanding of the pathogenesis of mastitis.
基金funded by the Integrated Demonstration of Scalable and Efficient Healthy Breeding for Cattle and Sheep(Grant No.2022YFD1301100)Instant Intelligent Diagnosis and Risk Warning Methods for Nutritional and Metabolic-Type Periparturient Cow Paralysis(Grant No.2024-YWF-ZYSQ-10)。
文摘Background Methane(CH_(4))emissions from ruminants significantly contribute to greenhouse gas effects and energy loss in livestock production.Methyl-coenzyme M reductase(MCR)is the key enzyme in methanogenesis,making it a promising target for CH_(4) mitigation.This study aimed to identify and validate plant-derived inhibitors by using molecular docking to screen compounds with strong binding affinity to the F430 active site of MCR and assessing their efficacy in reducing CH_(4) emissions.Results Molecular docking analysis identified salvianolic acid C(SAC)as a potent inhibitor of MCR,showing a strong binding affinity to the F430 active site(binding energy:-8.2 kcal/mol).Enzymatic inhibition assays confirmed its inhibitory effect,with a half-maximal inhibitory concentration(IC50)of 692.3μmol/L.In vitro rumen fermentation experiments demonstrated that SAC supplementation(1.5 mg/g DM)significantly reduced CH_(4)production(P<0.01)without negatively affecting major fermentation parameters.Microbial community analysis using 16S rRNA sequencing and metagenomics revealed that SAC selectively altered the rumen microbiota,increasing the relative abundance of Bacteroidota while significantly reducing Methanobrevibacter(P=0.04).Moreover,metagenomic analysis showed the downregulation of key methanogenesis-related genes(mcrA and rnfC),suggesting a dual mechanism involving direct enzymatic inhibition and microbial community modulation.Conclusions These findings indicate that SAC effectively reduces CH_(4)production by inhibiting MCR activity and reshaping the rumen microbial community.As a plant-derived compound with strong inhibitory effects on methanogenesis,SAC presents a promising and sustainable alternative to synthetic CH_(4) inhibitors,offering potential applications for mitigating CH_(4)emissions in livestock production.
基金financially supported by the National Key Research and Development Program of China(2023YFD2000701)the Natural Science Foundation of Heilongjiang Province,China(YQ2023C011)+1 种基金the Key Research and Development Program of Heilongjiang Province,China(Grant no.2022ZX01A24)the Key Laboratory of Low-carbon Green Agriculture in Northeastern China,Ministry of Agriculture and Rural Affairs of China(LCGANE14)。
文摘As a major contributor to methane production in agriculture,there is a need for a suitable methane inhibitor to reduce ruminant methane emissions and minimize the impact on the climate.This work aimed to explore the influence of cordycepin on rumen fermentation,gas production,microbiome and their metabolites.A total of 0.00,0.08,0.16,0.32,and 0.64 g L^(–1)cordycepin were added into fermentation bottles containing 2 g total mixed ration for in vitro ruminal fermentation,and then the gas produced and fermentation parameters were measured for each bottle.Samples from the 0 and 0.64 g L^(–1)cordycepin addition were selected for 16S rRNA gene sequencing and metabolome analysis.The result of this experiment indicated that the addition of cordycepin could linearly increase the concentration of total volatile fatty acid,ammonia nitrogen,the proportion of propionate,valerate,and isovalerate,and linearly reduce ruminal pH and methane,carbon dioxide,hydrogen and total gas production,as well as the methane proportion,carbon dioxide proportion and proportion of butyrate.In addition,there was a quadratic relationship between hydrogen and cordycepin addition.At the same time,the relative abundance of Succiniclasticum,Prevotella,Rikenellaceae_RC9_gut_group,NK4A214_group,Christensenellaceae_R_(7)_group,unclassified_F082,Veillonellaceae_UCG_001,Dasytricha,Ophryoscolex,Isotricha,unclassified_Eukaryota,Methanobrevibacter,and Piromyces decreased significantly after adding the maximum dose of cordycepin.In contrast,the relative abundance of Succinivibrio,unclassified_Succinivibrionaceae,Prevotellaceae_UCG_001,unclassified_Lachnospiraceae,Lachnospira,Succinivibrionaceae_UCG_002,Pseudobutyrivibrio,Entodinium,Polyplastron,unclassified_Methanomethylophilaceae,Methanosphaera,and Candidatus_Methanomethylophilus increased significantly.Metabolic pathways such as biosynthesis of unsaturated fatty acids and purine metabolism and metabolites such as arachidonic acid,adenine,and 2′-deoxyguanosine were also affected by the addition of cordycepin.Based on this,we conclude that cordycepin is an effective methane emission inhibitor that can change the rumen metabolites and fermentation parameters by influencing the rumen microbiome,thus regulating rumen methane production.This experiment may provide a potential theoretical reference for developing Cordyceps byproduct or additives containing cordycepin as methane inhibitors.
基金funded by UK Research and Innovation(UKRI)doctoral training grant no:BB/T008776/1the Department of Agriculture,Environment and Rural Affairs(DAERA)by Trouw Nutrition and by John Thompsons and Sons Ltd.
文摘Background Nitrogen-Use-Efficiency(NUE)in lactating dairy cows,defined as milk nitrogen(N)output as a proportion of N consumed,is low,with the majority of excess N excreted in manure.Excreted N can be lost to the environment as ammonia gas leading to environmental acidification and nutrient enrichment of sensitive habitats,and to watercourses contributing to aquatic eutrophication.While there is much evidence that NUE can be improved by reducing the crude protein(CP)content of dairy cow diets,the long-term impacts of feeding lower protein diets on cow performance and the rumen microbiome are less well understood.This study examined the effects of reducing the CP contents of dairy cow diets on cow performance,NUE,the relationship between NUE and residual feed intake(RFI),and the rumen microbiome.Results Dietary CP content did not affect feed intake,milk yield or milk composition(P>0.05),except for milk urea N(MUN),which increased with increasing diet CP content(P<0.05).The mean NUE was 34%,34%and 31%for the LCP(low-protein,15%),MCP(medium-protein,16%),and HCP(high-protein,17%)diets,respectively.RFI was negatively correlated with NUE(r=−0.57,P<0.001).The rumen ammonia-N concentrations increased with increasing dietary CP;however,the ruminal pH and volatile fatty acid(VFA)content of the rumen fluid remained constant.Predicted urinary N excretion was greater in the HCP and MCP diets than in the LCP diet.Reducing dietary CP content in dairy cow diets did not affect microbial composition,diversity and functional profiles.The family Bacteroidaceae was more abundant in HE(high-efficiency)cows,whereas the Methanobacteriaceae and the genus Methanobrevibacter were more abundant in LE(low-efficiency)cows.Additionally,propanoate metabolism,cysteine and methionine metabolism and amino acid biosynthesis pathways were more abundant in HE cows,whilst the methane(CH4)metabolism pathway was upregulated in LE cows.Conclusions The results demonstrate that diet CP can be reduced with no loss in cow performance,but with an associated reduction in N excretion.The abundance of microbial populations differed between low and high efficiency cows,which may contribute to the differences in efficiency observed.
基金supported by the National Natural Science Foundation of China(32072757 and U21A20250)。
文摘Yaks are well-adapted to the harsh environment of the Tibetan Plateau,and they emit less enteric methane(CH_(4))and digest poor-quality forage better than cattle.To examine the potential of yak rumen inoculum to mitigate CH_(4)production and improve digestibility in cattle,we incubated substrate with rumen inoculum from yak(YRI)and cattle(CRI)in vitro in five ratios(YRI:CRI):(1)0:100(control),(2)25:75,(3)50:50,(4)75:25 and(5)100:0 for 72 h.The YRI:CRI ratios of 50:50,75:25 and 100:0 produced less total gas and CH_(4)and accumulated less hydrogen(H_(2))than0:100(control)at most time points.From 12 h onwards,there was a linear decrease(P<0.05)in carbon dioxide(CO_(2))production with increasing YRI:CRI ratio.At 72 h,the ratios of 50:50 and 75:25 had higher dry matter(+7.71%and+4.11%,respectively),as well as higher acid detergent fiber digestibility(+15.5%and+7.61%,respectively),when compared to the 0:100 ratio(P<0.05).Increasing the proportion of YRI generally increased total VFA concentrations,and,concomitantly,decreased the proportion of metabolic hydrogen([2H])incorporated into CH_(4),and decreased the recovery of[2H].The lower[2H]recovery indicates unknown[2H]sinks in the culture.Estimated Gibbs free energy changes(ΔG)for reductive acetogenesis were negative,indicating the thermodynamic feasibility of this process.It would be beneficial to identify:1)the alternative[2H]sinks,which could help mitigate CH_(4)emission,and 2)core microbes involved in fiber digestion.This experiment supported lower CH_(4)emission and greater nutrient digestibility of yaks compared to cattle.Multi-omics combined with microbial culture technologies developed in recent years could help to better understand fermentation differences among species.
基金supported by the National Key R&D Program(Grant No.2022YFD1301101-1)National Natural Science Foundation of China(Grant No.32172758)Key Research and Development Program of Ningxia(Grant No.2024BBF01008)。
文摘Background In this study,the effects of L-leucine(Leu)on rumen fermentation parameters,rumen epithelium development,amino acid composition,rumen bacterial communities and rumen metabolites in beef cattle were investigated.Twenty-four fattening Angus females of similar initial weight(575.5±22.1 kg)were randomly assigned to 2 treatments with 4 replicate pens(3 cattle per pen).They were fed either a basal diet or a basal diet supplemented with 6.0 g L-Leu/100 kg BW/d for 120 d.Results(1)Leu increased the ruminal concentrations of total volatile fatty acid(VFA)(P=0.017),propionate(P=0.023),isovalerate(P=0.001),and branched-chain volatile fatty acid(BCVFA)(P=0.01)at 4 h post-feeding.It also tended to increase acetate(P=0.083)and decrease the ammonia-N(NH_3-N)concentration(P=0.055),but it did not affect ruminal pH(P>0.1).Leu also increased microbial crude protein(MCP)(P=0.026)at 4 h post-feeding,but decreased MCP at 8 h post-feeding(P=0.010).(2)Supplementation with L-Leu increased the ruminal concentrations of phenylalanine(P=0.011),lysine(P=0.034),and tyrosine(P=0.033),while decreasing the cystine concentration(P=0.010).(3)Leu increased the thickness of the stratum spinosum and basal(P<0.05),while decreasing the thickness of the stratum granulosum(P<0.05).(4)Leu upregulated the relative mRNA abundance of genes involved in tight junction proteins(P<0.05)and VFA absorption and metabolism(P<0.01)in the rumen epithelium.This upregulation was positively correlated with the concentrations ruminal isovalerate and BCVFA(P<0.01).(5)L-Leu did not affect the diversity and richness of ruminal microbes(P>0.05),but differential bacterial biomarkers(LEfSe,LDA>2)were either positively or negatively correlated with ruminal MCP,NH_3-N,and BCVFA concentrations(P<0.001).Additionally,differential bacterial metabolites(OPLS-DA,VIP>1.5)were primarily enriched in the amino acid metabolism pathway and the cofactors and vitamins metabolism pathway(P<0.05).Conclusions Dietary supplementation with L-Leu altered rumen fermentation parameters and patterns,improved rumen epithelial morphology,and enhanced the expression of genes related to VFA absorption and metabolism in the rumen epithelium of beef cattle.
基金funded by the Science and Technology Major Project of the Inner Mongolia Autonomous Region of China to the State Key Laboratory of Reproductive Regulation(2023KYPT0010 and 2021ZD0048)STI 2030-Major Projects(2023ZD0407504)of China+1 种基金the development plan for young scientific and technological talents in colleges and universities of Inner Mongolia Autonomous Region of China(NMGIRT2204)the National Natural Science Foundation of China(32160172).
文摘Epigenetic regulation in the rumen,a unique ruminant organ,remains largely unexplored compared with other tissues studied in model species.In this study,we perform an in-depth analysis of the epigenetic and transcriptional landscapes across fetal and adult bovine tissues as well as pluripotent stem cells.Among the extensive methylation differences across various stages and tissues,we identify tissue-specific differentially methylated regions(tsDMRs)unique to the rumen,which are crucial for regulating epithelial development and energy metabolism.These tsDMRs cluster within super-enhancer regions that overlap with transcription factor(TF)binding sites.Regression models indicate that DNA methylation,along with H3K27me3 and H3K27ac,can be used to predict enhancer activity.Key upstream TFs,including SOX2,FOSL1/2,and SMAD2/3,primarily maintain an inhibitory state through bivalent modifications during fetal development.Downstream functional genes are maintained mainly in a stable repressive state via DNA methylation until differentiation is complete.Our study underscores the critical role of tsDMRs in regulating distal components of rumen morphology and function,providing key insights into the epigenetic regulatory mechanisms that may influence bovine production traits.
基金funded by the Chief Scientist Program of Qinghai Province(2024-SF-102)the Joint Special Project of Sanjiangyuan National Park(LHZX-2023-02).
文摘Background As an indigenous livestock species on the Tibetan Plateau,Tibetan sheep exhibit remarkable adaptability to low temperatures and nutrient-scarce environments.During the cold season,Tibetan sheep are typically managed under two feeding regimes:barn feeding(BF)and traditional grazing(TG).However,the molecular mechanisms underlying their adaptation to these distinct management strategies remain unclear.This study aimed to investigate the adaptive strategies of rumen function in Tibetan sheep to cold-season feeding regimes by integrating analyses of rumen morphology,microbiome,metabolome,and transcriptome.Twelve healthy Tibetan sheep with similar body weights were assigned into two groups(BF vs.TG).At the end of the experiment,rumen tissues were subjected to histological observation.Multi-omics techniques were employed to evaluate the effects of cold-season feeding regimes on rumen function in Tibetan sheep.Results The ruminal papilla height,width,and muscular thickness were significantly higher in BF group.The relative abundances of Actinobacteria and Succiniclasticum were significantly elevated in the rumen of BF group,whereas Rikenellaceae,Gracilibacteria,and Lachnospiraceae showed higher abundances in the TG group.Metabolomic analysis identified 19 differential metabolites between the two groups,including upregulated compounds in BF group(fumaric acid,maltose,L-phenylalanine,and L-alanine)and TG group(e.g.,phenylacetic acid,salicyluric acid and ferulic acid).These metabolites were predominantly enriched in phenylalanine metabolism,alanine,aspartate and glutamate metabolism,and phenylalanine,tyrosine and tryptophan biosynthesis pathways.Additionally,210 differentially expressed genes(DEGs)were identified in rumen epithelium:100 upregulated DEGs in the BF group were enriched in nutrient metabolism-related pathways(e.g.,fatty acid degradation and PPAR signaling pathway),while 110 upregulated DEGs in the TG group were associated with immune-related pathways(e.g.,p53 signaling pathway and glutathione metabolism).Conclusions Among these,we observed distinct rumen functional responses to different cold-season feeding regimes in Tibetan sheep and revealed energy allocation strategies mediated by host-microbe interactions.In the BF group,Tibetan sheep adopted a"metabolic efficiency-priority"strategy,driving rumen microbiota to maximize energy capture from high-nutrient diets to support host growth.In contrast,the TG group exhibited an"environmental adaptation-priority"strategy,where rumen microbiota prioritized cellulose degradation and anti-inflammatory functions,reallocating energy toward homeostasis maintenance at the expense of rumen development and growth performance.
基金funded by National Key Research and Development Program(2022YFA1304200)Agricultural Science and Technology Innovation Program(CAAS-ASTIP-2023-IFR-04 and CAAS-ZDRW202305)the Beijing Innovation Consortium of Livestock Research System(BAIC05-2023).
文摘Background Rumen microorganisms are key regulators of ruminant growth and production performance.Identifying probiotic candidates through microbial culturomics presents a promising strategy for improving ruminant production performance.Our previous study identified significant differences in rumen microbial communities of Holstein calves with varying average daily gain(ADG).This study aims to identify a target strain based on the findings from multi-omics analysis and literature review,isolating and evaluating the target microbial strains from both the rumen and hindgut contents for their probiotic potential.Results Parabacteroides distasonis,a strain closely associated with ADG,was successfully isolated from calf rumen content cultured with Fastidious Anaerobe Agar(FAA)medium and named Parabacteroides distasonis F4.Wholegenome sequencing and pan-genome analysis showed that P.distasonis F4 possesses a core functional potential for carbohydrate and amino acid metabolism,with the ability to produce propionate,acetate,and lactate.The results of targeted and untargeted metabolomics further validated the organic acid production and metabolic pathways of P.distasonis F4.An in vitro simulated rumen fermentation test showed that supplementation with P.distasonis F4 significantly altered rumen microbial community structure and increased the molar proportions of propionate and butyrate in the rumen.Furthermore,an in vivo study demonstrated that dietary supplementation with P.distasonis F4 significantly increased the ADG of pre-weaning calves.Conclusions This study represents the first isolation of P.distasonis F4 from rumen,highlighting its potential as a probiotic strain for improving rumen development and growth performance in ruminants.
基金supported by the National Key Research and Development Program of China(2023YFE0100400)Science and Technology Project of Inner Mongolia Autonomous Region(2020GG0036)+2 种基金Basic Scientific Research Business Project of Universities directly under the Inner Mongolia Autonomous Region(BR22-11-17)National Center of Technology Innovation for Dairy(2023-JSGG-5)the Special Project for Improving the Research Ability of Young Teachers of Inner Mongolia Agricultural University(BR220133).
文摘Background Using yeast culture as additives in ruminant feed prevents rumen microbial dysbiosis,enhances performance,and regulates rumen pH.The yeast culture used in this study was developed in-house,and has been shown to promote rumen epithelial growth in several sheep trials.Changes in protein expression associated with the promotion of rumen epithelial development following the addition of yeast culture,along with the associated molecular mechanisms,remain unknown.We used 2045-day-old weaned lambs to investigate the specific proteins and molecular mechanisms involved in these processes.Half of the lambs were fed yeast culture,and the other half were used as controls.Results Yeast culture enhanced growth performance,facilitated rumen fermentation,and promoted rumen papilla development in weaned lambs.Proteomics data identified 4,831 proteins in the rumen epithelial tissue of lambs,comprising 87 upregulated and 425 downregulated proteins.Administration of yeast culture activated multiple molecular functions within rumen epithelial cells,including oxidative phosphorylation,glutathione metabolism,apoptosis,cell cycle,and vitamin digestion and absorption.The expression of proteins associated with cell cycle regulation increased,whereas those associated with apoptosis decreased.Administration of yeast culture also reduced the duration of the G0/G1 phase of rumen epithelial cells and accelerated the cell cycle.Furthermore,yeast culture showed increased cyclin D1,cyclin-dependent kinase(CDK)2,CDK4,CDK6,and cyclin E1 expressions and decreased cytochrome C(Cyto-c),Bcl-2-related X protein(Bax),cleaved caspase 3(C-caspase 3),caspase 3,and cleaved caspase 7(C-caspase 7)protein expressions.Yeast culture upregulated the insulin-like growth factor-1 receptor(IGF-1R)and insulin-like growth factor-binding protein 5(IGFBP-5)mRNA expressions in rumen epithelial cells.Conclusions Yeast culture facilitates rumen epithelial development by regulating the cell cycle and IGF-1 signaling and reducing the expression of proteins associated with apoptosis in rumen epithelial cells.The findings of this study provide novel insights into the molecular mechanisms through which yeast culture promotes rumen epithelial development in weaned lambs.
基金supported by China Agriculture Research System of MOF and MARA(CARS-38)。
文摘The aim of this study was to investigate the effects of dietary fat on energy and nitrogen(N)metabolism efficiency,rumen fermentation,and microbiota in twin suckling lambs.Thirty pairs of twin male lambs were randomly divided into two groups with one group receiving a high-fat diet(HF)and the other a normal-fat diet(NF).Two diets(milk replacer and starter)of equal protein and different fat levels.The metabolism test was conducted when the lambs were 50-60 days old,and nine pairs of twin lambs were randomly selected for slaughter to collect rumen fluid at 60 days old.The result showed that fat addition increased the final body weight(BW),ruminal ammonia nitrogen(NH_(3)-N)content,proportion of propionic acid,and estimated methane production(CH_(4e))(P<0.05).The high fat diet tended to improve digestive energy(DE),metabolism energy(ME),DE/ME,utilisation of N(0.05<P<0.1).However,microbial crude protein(MCP)content,total volatile fatty acids(VFA),acetic acid ratio,and the ratio of acetate to propionate(A:P)were lower than that in the NF group(P<0.05).Regardless of whether fat is added or not,no different were observed in blood metabolites between the treatment.High-throughput sequencing revealed that fat addition before weaning increased phyla Proteobacteria and genera of Succinivibrio,but decreased the relative abundance of Clostridium IV,Dialister,Roseburia,Acidaminococcus,and Megasphaera genera.These findings indicated that high fat diet improved body weight,energy and nitrogen utilization may by shifting the rumen toward propionate fermentation via the enrichment of Succinivibrio.
基金supported by the Fundacao de Amparo a Pesquisa do Estado de Sao Paulo(FAPESP,Sao Paulo,SP,BRAZIL)for the scholarship of the first authors(2019/24820-3 and 2022/00989-1)and the PDIP grant(2017/50339-5).
文摘Background The environmental impact of feedlot operations is a growing concern,as cattle excrete a significant portion of feed nutrients as waste.Exogenous feed enzymes(EFE)have gained interest for their potential to enhance feed efficiency in ruminants by improving nutrient digestion.However,EFE effects on ruminal parameters have shown inconsistencies,with limited research on nitrogen metabolism and rumen microbiome impacts.Moreover,the synergistic effects of combining different EFEs remain unclear.This study aimed to evaluate the effects of individual and combined EFE products in feedlot diets on ruminal fermentation parameters,nitrogen metabolism,and ruminal microbial communities.Ten rumen-cannulated Nellore steers[543±28.6 kg of body weight(BW)]were distributed in a replicated Latin-square design(5×5)in individual pens.Treatments included:control(CON,no EFE supplementation),amylase[AML,0.5 g/kg of diet dry matter(DM)],xylanase(FBL,0.9 g/kg DM),half dose combination(HD,0.25 g of AML+0.45 g of FBL/kg of DM),and full dose combination(FD,0.5 g of AML+0.90 g of FBL/kg of DM).The experimental period lasted 19 d and included total urine and feces collection(d 15 to 18)and rumen fluid sampling(d 19)at 0,4,8,12,and 16 h post-feeding for ammonia,volatile fatty acids(VFA),pH and microbiome analysis.Results EFE supplemented animals exhibited lower ruminal ammonia concentrations(P=0.040),and higher acetate proportions(P<0.001)compared to the control group.EFE supplementation resulted in reduced nitrogen(N)excretion in feces(P=0.049)and urine(P=0.036),contributing to improved N retention and efficiency(P=0.045).Additionally,EFE products induced shifts in various microbial taxa at family and genera levels(P≤0.10),which may be associated with the changes observed in ruminal fermentation.Conclusions Our findings demonstrate that EFE supplementation enhances nitrogen retention,reduces ruminal ammonia,and alters ruminal fermentation profiles and microbial populations in feedlot cattle.While the expected synergism between amylase and xylanase did not significantly impact rumen fermentation parameters,it did induce shifts in the rumen microbiome.These results suggest that EFE supplementation may be a promising strategy for improving nutrient utilization and potentially reducing the environmental impact of feedlot operations.
基金Supported by Natural Science Foundation Key Project of Xinjiang Uygur Autonomous Region(2022D01D10)China Agricultural Industry Research System of Xinjiang Uygur Autonomous Region in 2024(XJARS-12-05)Project of Key Laboratory of Animal Nutrition and Feed of Yili Prefecture.
文摘[Objective]The paper was to investigate the effects of substituting corn pellets with potato residue on the growth performance,rumen fermentation indicators and economic benefits of Xinjiang Brown cattle.[Method]A total of 80 Xinjiang Brown cattle,each 22 months old and with a similar body weight of(250±15)kg,were randomly assigned to four groups,with 20 cattle in each group,utilizing a single-factor experimental design.The total mixed diets for the experimental groups Ⅰ,Ⅱ,and Ⅲ were formulated by substituting corn pellets with 2.00%,4.00%,and 6.00%potato residue,respectively,while the diet in the control group was not substituted with potato residue.The duration of the test was 100 d,which comprised a pre-test period of 10 d and a formal test period of 90 d.During the test period,the average dry matter intake,average daily weight gain and feed-gain ratio were assessed at 30-day intervals,and body size indicators were measured on days 0 and 90.Rumen fluid samples were collected from the oral cavity on days 0,30,60,and 90 to assess rumen fermentation parameters.Additionally,jugular blood samples were obtained during the fasting period,and serum was separated for the analysis of total protein mass concentration,urea nitrogen,and glucose concentration.Furthermore,the economic benefits accrued during the test period were calculated.[Result]The dry matter intake in experimental group Ⅰ was significantly higher than that in the control group from days 31 to 60(P<0.05).In contrast,the differences in dry matter intake between experimental groups Ⅱ and Ⅲ and the control group were not statistically significant(P>0.05).From days 61 to 90,the dry matter intake in experimental group Ⅰ remained significantly higher than that in the other groups(P<0.05).Throughout the entire experimental period,the average daily weight gain observed in experimental group Ⅰ was significantly greater than that recorded in the other groups(P<0.05).Additionally,the total weight gain over the entire period was significantly higher than that of experimental group Ⅱ(P<0.05)and markedly higher than that of both the control group and experimental group Ⅲ(P<0.01).The feed-gain ratio in experimental group Ⅰ was significantly lower than that in experimental group Ⅱ(P<0.05).There were no statisticaly significant differences observed in body height,slope length,thoracic circumference,abdominal circumference,rumen pH,acetic acid,propionic acid,butyric acid,valeric acid,total volatile fatty acids,and ammoniacal nitrogen mass concentration among the groups(P>0.05).On the 90th day of the experiment,the serum urea nitrogen concentration in beef cattle from experimental groups Ⅰ and Ⅱ was significantly lower than that in the control group and experimental group Ⅲ(P<0.05).Additionally,the profit margins in experimental groups Ⅰ,Ⅱ,and Ⅲ were higher than those in the control group,and the profit margin in experimental group Ⅰ was the highest.[Conclusion]The substitution of corn pellets with potato residue has the potential to enhance the average daily weight gain and total weight gain throughout the entire period in beef cattle,while simultaneously reducing the feed-gain ratio.However,this substitution does not appear to have a significant impact on body size indicators,rumen fermentation parameters,or the concentrations of serum total protein and glucose in beef cattle.Furthermore,this approach may yield improved breeding profitability,with a recommended substitution ratio of 2.00%based on the conditions of this experiment.
基金supported by the National Key Research and Development Program for International Science and Technology Innovation Cooperation between Governments(2023YFE0111800)the Shaanxi Province’s San Qin Talent Attraction Program for Regional Youth Talents.
文摘Background Subacute rumen acidosis(SARA)is a common metabolic disorder in ruminants that disrupts the rumen microbiome and animal health,but diagnosis is challenging due to subtle symptoms and invasive testing require-ments.This study explores the potential of the buccal(oral)microbiome as a diagnostic indicator for SARA,hypoth-esizing an interaction with the rumen microbiome.Results The study involved 47 dairy goats,including 11 on a control diet and 36 on high-concentrate diets with increasing rumen-degradable starch.Animals were grouped based on dietary exposure and ruminal pH:Control,Low-RDS Tolerance/SARA(LRDST/LRDSS),and High-RDS Tolerance/SARA(HRDST/HRDSS).Transcriptomics of rumen epithelium showed heightened inflammatory pathway gene expression in SARA-susceptible goats compared to controls and tolerant groups.Alpha diversity of ruminal bacteria showed lower Shannon diversity in HRDSS goats compared to HRDST whereas buccal bacteria displayed significantly lower Chao1 diversity in LRDSS goats compared to HRDST.Beta diversity analyses revealed distinct patterns between SARA-affected goats and healthy controls in both ruminal and buccal microbiomes.Prevotellaceae_UCG-003 emerged as a candidate biomarker,with reduced abundance in SARA-susceptible goats in both rumen and buccal samples.Machine learning classifiers achieved high accuracy in distinguishing SARA-susceptible goats using this genus(rumen AUC=0.807;buccal AUC=0.779).Source tracking analysis illustrated diminished cross-population of bacteria from the buccal to rumen(2.86%to 0.25%)and vice versa(8.59%to 1.17%),signifying compromised microbial interchange in SARA-affected goats.A microbiota transplant experiment verified SARA microbiota’s ability to induce pH decline,escalate inflammation-related gene expression(MAPK10,IL17B,FOSB,SPP1),disrupt microbial transfer,and reduce Prevotellaceae_UCG-003 in recipients.Conclusion Our findings highlight SARA’s dual impact on ruminal and buccal microbiota,exacerbating epithelial inflammation gene expression.Shifts in the buccal microbiome,specifically reductions in Prevotellaceae_UCG-003,mirror ruminal changes and can be influenced by inter-compartmental bacterial transmission,thereby offering a non-invasive diagnostic approach for SARA.
基金National Key R&D Program of China(Beijing,China,grant no.2023YFE0116900 and 2023YFD1801400)National Natural Science Foundation of China(Beijing,China,grant no.32473105,32302943,and 32302941)Postdoctoral Fellowship Program of CPSF(GZC20230951).
文摘Background During the transition period,excessive negative energy balance(NEB)lead to metabolic disorders and reduced milk yield.Rumen microbes are responsible for resolving plant material and producing volatile fatty acids(VFA),which are the primary energy source for cows.In this study,we aimed to investigate the effect of citrus peel extract(CPE)supplementation on rumen microbiota composition,energy metabolism and milk performance of peri-partum dairy cows.Methods Dairy cows were fed either a basal diet(CON group)or the same basal diet supplemented with CPE via intragastric administration(4 g/d,CPE group)for 6 weeks(3 weeks before and 3 weeks after calving;n=15 per group).Samples of serum,milk,rumen fluid,adipose tissue,and liver were collected to assess the effects of CPE on rumen microbiota composition,rumen fermentation parameters,milk performance,and energy metabolic status of dairy cows.Results CPE supplementation led to an increase in milk yield,milk protein and lactose contents,and serum glucose levels,while reduced serum concentrations of non-esterified fatty acid,β-hydroxybutyric acid,insulin,aspartate aminotransferase,alanine aminotransferase,and haptoglobin during the first month of lactation.CPE supplemen-tation also increased the content of ruminal VFA.Compared to the CON group,the abundance of Prevotellaceae,Methanobacteriaceae,Bacteroidales_RF16_group,and Selenomonadaceae was found increased,while the abun-dance of Oscillospiraceae,F082,Ruminococcaceae,Christensenellaceae,Muribaculaceae UCG-011,Saccharimona-daceae,Hungateiclostridiaceae,and Spirochaetaceae in the CPE group was found decreased.In adipose tissue,CPE supplementation decreased lipolysis,and inflammatory response,while increased insulin sensitivity.In the liver,CPE supplementation decreased lipid accumulation,increased insulin sensitivity,and upregulated expression of genes involved in gluconeogenesis.Conclusions Our findings suggest that CPE supplementation during the peripartum period altered rumen micro-biota composition and increased ruminal VFA contents,which further improved NEB and lactation performance,alleviated lipolysis and inflammatory response in adipose tissue,reduced lipid accumulation and promoted gluconeo-genesis in liver.Thus,CPE might contribute to improve energy metabolism and consequently lactation performance of dairy cows during the transition period.
基金partially granted by the Hi-Ga project,which is part of the programme of the Green ERA-Hub that has received funding from the European Union’s Horizon Europe research and innovation programme under Grant Agreement No.101056828self-financed by the DINAMIC team of the UMR Herbivores(INRAE,VetAgro Sup,Saint-Genès-Champanelle,France)。
文摘Background Insect meals have been identified as innovative and sustainable feedstuffs that could be used in ruminant nutrition.However,current research on the effects that their processing may have on rumen digestibility and fatty acid(FA)biohydrogenation is scant.This trial aims to investigate the effects(i)of drying temperature of fullfat Hermetia illucens(HI)and Tenebrio molitor(TM)meals,and(ii)of residual ether extract(EE)content of defatted HI and TM meals,on their fermentation characteristics and FA of rumen digesta after 24-h in vitro rumen incubation.Methods The tested full-fat meals included four HI and four TM meals obtained applying drying temperatures ranging from 30℃ to 70℃,while the tested defatted meals consisted of five HI and two TM meals containing a residual EE content ranging from 4.7 to 19.7 g EE/100 g dry matter(DM).The applied statistical models(GLM ANOVA)tested the effects of insect species,drying temperature(full-fat meals)or EE content(defatted meals),and their interaction.Results Drying temperature had minor effects on in vitro ruminal digestibility and FA profile of rumen digesta.Irrespective of insect species,increasing the drying temperature led to a reduction of in vitro degradation of proteins from insect meals,as outlined by the significant decrease in ammonia production(-0.009 mmol/g DM and-0.126 g/100 g total N for each additional 1℃).Irrespective of insect species,defatting increased total gas,volatile fatty acids(VFA)and CH_(4) productions,and the proportions of total saturated and branched-chain FA in rumen digesta(+0.038 mmol/g DM,+0.063 mmol/g DM,+12.9μmol/g DM,+0.18 g/100 g FA,and+0.19 g/100 g FA for each reduced 1 g EE/100 g DM,respectively),and reduced the proportion of total PUFA(-0.12 g/100 g FA).Conclusions The applied drying temperatures of full-fat insect meals are too low to exert impactful effects on rumen digestibility and FA biohydrogenation.Fat lowered fermentation activity,probably because of an inhibitory effect on rumen microbiota.The increased ruminal digestibility of defatted insect meals suggests that they can be more suitable to be used in ruminant nutrition than full-fat ones.
文摘[Objective] The aim of this study is to understand the population composition of methanogens in rumen fluid of grazing Inner Mongolian cashmere goat. [Method] Total DNAs of various bacteria in rumen fluid were isolated for PCR amplification using the specifically designed primers based on conservative mcrA sequence of methanogens; then mcrA specific clone library was accordingly established. The restriction fragment length polymorphism(RFLP) of the library was further analyzed by digestion of restriction enzyme Taq I. [Result] One hundred and five randomly selected specific colonies were classified into six RFLP types, among which the dominant type accounts for 38%, and other types account for 27%, 18%, 5.5% and 4.5%, respectively. [Conclusion] There are at least six different methanogens in rumen fluid of grazing Inner Mongolian cashmere goat.
基金Supported by National Natural Science Foundation of China(30960256,31060314)Project of Yunnan Education Department(V09Y0202)~~
文摘[Objective]The paper was to provide reference for further study and development of gayal（Bos frontalis）.[Method]According to the research status at home and abroad,the biological characteristics and rumen microorganisms of gayal in Yunnan Province was studied.[Result]Gayal in Yunnan had typical body form and very good meat production performance,its muscle fiber diameter was significantly less than other kinds of cattle;the water holding ratio,muscle tenderness and muscle succulency were significantly higher than others;its amount,shape and structure of chromosome were different from yellow cattle（Bos taurus）and wild cattle（Bos gaurus）,and the amounts of those chromosomes（2n）were 58,60 and 56,respectively.It could create hybrid with yellow cattle;the gayal＇s special diet was bamboo,its in vitro dry matter digestibility（IVDMD）on various crude forage was significantly higher than yellow cattle in Yunnan;the viable bacteria and cellulolytic bacteria in rumen were 4.51×109 and 1.63×109 CFU/ml,which was significantly higher than yellow cattle in Yunnan,its dominant bacteria in rumen mainly was cellulolytic bacteria.[Conclusion]Gayal not only had high academic value,but also had a great development value.
