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Singh, K. M., A. K. Tripathi, P. R. Pandya, S. Parnerkar, R. K. Kothari i C. G. Joshi. "Molecular Genetic Diversity and Quantitation of Methanogen in Ruminal Fluid of Buffalo (Bubalus bubalis) Fed Ration (Wheat Straw and Concentrate Mixture Diet)". Genetics Research International 2013 (5.06.2013): 1–7. http://dx.doi.org/10.1155/2013/980191.
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High roughage diet causes more methane emissions; however, the total methanogen abundance is not influenced by roughage proportion. Technologies to reduce methane emissions are lacking, and development of inhibitors and vaccines that mitigate rumen-derived methane by targeting methanogens relies on present knowledge of the methanogens. In this work, we have investigated molecular diversity of rumen methanogens of Surti buffalo. DNA from rumen fluid was extracted, and 16S rRNA encoding genes were amplified using methanogen specific primer to generate 16S rDNA clone libraries. Seventy-six clones were randomly selected and analysed by RFLP resulting in 21 operational taxonomic units (OTUs). BLAST analysis with available sequences in database revealed sequences of 13 OTUs (55 clones) showing similarity with Methanomicrobium sp, 3 OTUs (15 clones) with Methanobrevibacter sp. The remaining 5 OTUs (6 clones) belonged to uncultured archaea. The phylogenetic analysis indicated that methanogenic communities found in the library were clustered in the order of Methanomicrobiales (18 OTUs) and Methanobacteriales (3 OTUs). The population of Methanomicrobiales, Methanobacteriales, and Methanococcales were also observed, accounting for 1.94%, 0.72%, and 0.47% of total archaea, respectively.
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Williams, Yvette J., Sam Popovski, Suzanne M. Rea, Lucy C. Skillman, Andrew F. Toovey, Korinne S. Northwood i André-Denis G. Wright. "A Vaccine against Rumen Methanogens Can Alter the Composition of Archaeal Populations". Applied and Environmental Microbiology 75, nr 7 (6.02.2009): 1860–66. http://dx.doi.org/10.1128/aem.02453-08.
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ABSTRACT The objectives of this study were to formulate a vaccine based upon the different species/strains of methanogens present in sheep intended to be immunized and to determine if a targeted vaccine could be used to decrease the methane output of the sheep. Two 16S rRNA gene libraries were used to survey the methanogenic archaea in sheep prior to vaccination, and methanogens representing five phylotypes were found to account for >52% of the different species/strains of methanogens detected. A vaccine based on a mixture of these five methanogens was then formulated, and 32 sheep were vaccinated on days 0, 28, and 103 with either a control or the anti-methanogen vaccine. Enzyme-linked immunosorbent assay analysis revealed that each vaccination with the anti-methanogen formulation resulted in higher specific immunoglobulin G titers in plasma, saliva, and rumen fluid. Methane output levels corrected for dry-matter intake for the control and treatment groups were not significantly different, and real-time PCR data also indicated that methanogen numbers were not significantly different for the two groups after the second vaccination. However, clone library data indicated that methanogen diversity was significantly greater in sheep receiving the anti-methanogen vaccine and that the vaccine may have altered the composition of the methanogen population. A correlation between 16S rRNA gene sequence relatedness and cross-reactivity for the methanogens (R 2 = 0.90) also exists, which suggests that a highly specific vaccine can be made to target specific strains of methanogens and that a more broad-spectrum approach is needed for success in the rumen. Our data also suggest that methanogens take longer than 4 weeks to adapt to dietary changes and call into question the validity of experimental results based upon a 2- to 4-week acclimatization period normally observed for bacteria.
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Ohene-Adjei, Samuel, Ronald M. Teather, Michael Ivan i Robert J. Forster. "Postinoculation Protozoan Establishment and Association Patterns of Methanogenic Archaea in the Ovine Rumen". Applied and Environmental Microbiology 73, nr 14 (18.05.2007): 4609–18. http://dx.doi.org/10.1128/aem.02687-06.
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ABSTRACT Association patterns between archaea and rumen protozoa were evaluated by analyzing archaeal 16S rRNA gene clone libraries from ovine rumen inoculated with different protozoa. Five protozoan inoculation treatments, fauna free (negative control), holotrich and cellulolytic protozoa, Isotricha and Dasytricha spp., Entodinium spp., and total fauna (type A) were tested. We used denaturing gradient gel electrophoresis, quantitative PCR, and phylogenetic analysis to evaluate the impact of the protozoan inoculants on the respective archaeal communities. Protozoan 18S ribosomal DNA clone libraries were also evaluated to monitor the protozoal population that was established by the inoculation. Phylogenetic analysis suggested that archaeal clones associated with the fauna-free, the Entodinium, and the type A inoculations clustered primarily with uncultured phylotypes. Polyplastron multivesiculatum was the predominant protozoan strain established by the holotrich and cellulolytic protozoan treatment, and this resulted predominantly in archaeal clones affiliated with uncultured and cultured methanogenic phylotypes (Methanosphaera stadtmanae, Methanobrevibacter ruminantium, and Methanobacterium bryantii). Furthermore, the Isotricha and Dasytricha inoculation treatment resulted primarily in archaeal clones affiliated with Methanobrevibacter smithii. This report provides the first assessment of the influence of protozoa on archaea within the rumen microbial community and provides evidence to suggest that different archaeal phylotypes associate with specific groups of protozoa. The observed patterns may be linked to the evolution of commensal and symbiotic relationships between archaea and protozoa in the ovine rumen environment. This report further underscores the prevalence and potential importance of a rather large group of uncultivated archaea in the ovine rumen, probably unrelated to known methanogens and undocumented in the bovine rumen.
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Yu, Zhongtang, Rubén García-González, Floyd L. Schanbacher i Mark Morrison. "Evaluations of Different Hypervariable Regions of Archaeal 16S rRNA Genes in Profiling of Methanogens by Archaea-Specific PCR and Denaturing Gradient Gel Electrophoresis". Applied and Environmental Microbiology 74, nr 3 (14.12.2007): 889–93. http://dx.doi.org/10.1128/aem.00684-07.
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ABSTRACT Different hypervariable (V) regions of the archaeal 16S rRNA gene (rrs) were compared systematically to establish a preferred V region(s) for use in Archaea-specific PCR-denaturing gradient gel electrophoresis (DGGE). The PCR products of the V3 region produced the most informative DGGE profiles and permitted identification of common methanogens from rumen samples from sheep. This study also showed that different methanogens might be detected when different V regions are targeted by PCR-DGGE. Dietary fat appeared to transiently stimulate Methanosphaera stadtmanae but inhibit Methanobrevibacter sp. strain AbM4 in rumen samples.
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Attwood, Graeme, i Christopher McSweeney. "Methanogen genomics to discover targets for methane mitigation technologies and options for alternative H2 utilisation in the rumen". Australian Journal of Experimental Agriculture 48, nr 2 (2008): 28. http://dx.doi.org/10.1071/ea07203.
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Reducing ruminant methane emissions is an important objective for ensuring the sustainability of ruminant-based agriculture. Methane is formed in the rumen by methanogens (part of the domain Archaea), mainly from H2 and CO2. Methanogens from a wide range of habitats are being genome-sequenced to gain a better understanding of their biology and, in particular, to identify targets for inhibition technologies for gut-associated methanogens. Genome comparisons are identifying common genes that define a methanogen, while gene differences are providing an insight into adaptations that allow methanogen survival and persistence under different environmental conditions. Within the rumen microbial food web, methanogens perform the beneficial task of removing H2, which allows reduced cofactors to be reoxidised and recycled, thereby enhancing the breakdown and fermentation of plant material. Therefore, rumen methane mitigation strategies need to consider alternative routes of H2 utilisation in the absence (or decreased levels) of methanogenesis to maintain rumen function. Two main alternatives are possible: enhancing rumen microorganisms that carry out reductive acetogenesis (combining CO2 and H2 to form acetate) or promotion of organisms that consume reducing equivalents during the conversion of metabolic intermediates (malate, fumarate and crotonate) into propionate and butyrate. A better understanding of the role and scale of methane oxidation in the rumen may also lead to future options for methane mitigation.
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Chaban, Bonnie, Sandy Y. M. Ng i Ken F. Jarrell. "Archaeal habitats — from the extreme to the ordinary". Canadian Journal of Microbiology 52, nr 2 (1.02.2006): 73–116. http://dx.doi.org/10.1139/w05-147.
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The domain Archaea represents a third line of evolutionary descent, separate from Bacteria and Eucarya. Initial studies seemed to limit archaea to various extreme environments. These included habitats at the extreme limits that allow life on earth, in terms of temperature, pH, salinity, and anaerobiosis, which were the homes to hyper thermo philes, extreme (thermo)acidophiles, extreme halophiles, and methanogens. Typical environments from which pure cultures of archaeal species have been isolated include hot springs, hydrothermal vents, solfataras, salt lakes, soda lakes, sewage digesters, and the rumen. Within the past two decades, the use of molecular techniques, including PCR-based amplification of 16S rRNA genes, has allowed a culture-independent assessment of microbial diversity. Remarkably, such techniques have indicated a wide distribution of mostly uncultured archaea in normal habitats, such as ocean waters, lake waters, and soil. This review discusses organisms from the domain Archaea in the context of the environments where they have been isolated or detected. For organizational purposes, the domain has been separated into the traditional groups of methanogens, extreme halophiles, thermoacidophiles, and hyperthermophiles, as well as the uncultured archaea detected by molecular means. Where possible, we have correlated known energy-yielding reactions and carbon sources of the archaeal types with available data on potential carbon sources and electron donors and acceptors present in the environments. From the broad distribution, metabolic diversity, and sheer numbers of archaea in environments from the extreme to the ordinary, the roles that the Archaea play in the ecosystems have been grossly underestimated and are worthy of much greater scrutiny.Key words: Archaea, methanogen, extreme halophile, hyperthermophile, thermoacidophile, uncultured archaea, habitats.
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Wright, Andr�-Denis G., Andrew J. Williams, Barbara Winder, Claus T. Christophersen, Sharon L. Rodgers i Kellie D. Smith. "Molecular Diversity of Rumen Methanogens from Sheep in Western Australia". Applied and Environmental Microbiology 70, nr 3 (marzec 2004): 1263–70. http://dx.doi.org/10.1128/aem.70.3.1263-1270.2004.
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ABSTRACT The molecular diversity of rumen methanogens in sheep in Australia was investigated by using individual 16S rRNA gene libraries prepared from the rumen contents obtained from six merino sheep grazing pasture (326 clones), six sheep fed an oaten hay-based diet (275 clones), and five sheep fed a lucerne hay-based diet (132 clones). A total of 733 clones were examined, and the analysis revealed 65 phylotypes whose sequences (1,260 bp) were similar to those of cultivated methanogens belonging to the order Methanobacteriales. Pasture-grazed sheep had more methanogen diversity than sheep fed either the oaten hay or lucerne hay diet. Methanobrevibacter strains SM9, M6, and NT7 accounted for over 90% of the total number of clones identified. M6 was more prevalent in grazing sheep, and SM9, despite being found in 16 of the 17 sheep, was more prevalent in sheep fed the lucerne-based diet. Five new species were identified. Two of these species exhibited very little sequence similarity to any cultivated methanogens and were found eight times in two of the six sheep that were grazing pasture. These unique sequences appear to represent a novel group of rumen archaea that are atypical for the rumen environment.
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Malik, P. K., S. Trivedi, A. Mohapatra, A. P. Kolte, V. Sejian, R. Bhatta i H. Rahman. "Comparison of enteric methane yield and diversity of ruminal methanogens in cattle and buffaloes fed on the same diet". PLOS ONE 16, nr 8 (11.08.2021): e0256048. http://dx.doi.org/10.1371/journal.pone.0256048.
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An in vivo study was conducted to compare the enteric methane emissions and diversity of ruminal methanogens in cattle and buffaloes kept in the same environment and fed on the same diet. Six cattle and six buffaloes were fed on a similar diet comprising Napier (Pennisetum purpureum) green grass and concentrate in 70:30. After 90 days of feeding, the daily enteric methane emissions were quantified by using the SF6 technique and ruminal fluid samples from animals were collected for the diversity analysis. The daily enteric methane emissions were significantly greater in cattle as compared to buffaloes; however, methane yields were not different between the two species. Methanogens were ranked at different taxonomic levels against the Rumen and Intestinal Methanogen-Database. The archaeal communities in both host species were dominated by the phylum Euryarchaeota; however, Crenarchaeota represented <1% of the total archaea. Methanogens affiliated with Methanobacteriales were most prominent and their proportion did not differ between the two hosts. Methanomicrobiales and Methanomassillicoccales constituted the second largest group of methanogens in cattle and buffaloes, respectively. Methanocellales (Methanocella arvoryza) were exclusively detected in the buffaloes. At the species level, Methanobrevibacter gottschalkii had the highest abundance (55–57%) in both the host species. The relative abundance of Methanobrevibacter wolinii between the two hosts differed significantly. Methanosarcinales, the acetoclastic methanogens were significantly greater in cattle than the buffaloes. It is concluded that the ruminal methane yield in cattle and buffaloes fed on the same diet did not differ. With the diet used in this study, there was a limited influence (<3.5%) of the host on the structure of the ruminal archaea community at the species level. Therefore, the methane mitigation strategies developed in either of the hosts should be effective in the other. Further studies are warranted to reveal the conjunctive effect of diet and geographical locations with the host on ruminal archaea community composition.
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Pandey, Ashish Kumar, Neelava Das, Kumar A. Muthu i Srinivasa Rao. "Methanogens in the Environment: An Insight of Methane Yield and Impact on Global Climate Change". International Letters of Natural Sciences 37 (kwiecień 2015): 51–60. http://dx.doi.org/10.18052/www.scipress.com/ilns.37.51.
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Methane is a most important greenhouse gas for planetary heating and it’s produced by methanogenic microorganisms as a metabolic byproduct and creates climate change. Methanogens are ancient organisms on earth found in anaerobic environments and methane is a key greenhouse gas concerned with methanogens. Therefore here is intense interest to writing this paper. A number of experiments have already conducted to study the methanogens in various environments such as rumen and intestinal system of animals, fresh water and marine sediments, swamps and marshes, hot springs, sludge digesters, and within anaerobic protozoa which utilize carbon dioxide in the presence of hydrogen and produce methane. The diversity of methanogens, belong to the domain Archaea and get involved in biological production of methane that catalyzes the degradation of organic compound as a part of global carbon cycle called methanogenesis. Majorly in this article we summaries the diversity of methanogens and their impact on global warming.
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Faseleh Jahromi, Mohammad, Juan Boo Liang, Rosfarizan Mohamad, Yong Meng Goh, Parisa Shokryazdan i Yin Wan Ho. "Lovastatin-Enriched Rice Straw Enhances Biomass Quality and Suppresses Ruminal Methanogenesis". BioMed Research International 2013 (2013): 1–13. http://dx.doi.org/10.1155/2013/397934.
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The primary objective of this study was to test the hypothesis that solid state fermentation (SSF) of agro-biomass (using rice straw as model); besides, breaking down its lignocellulose content to improve its nutritive values also produces lovastatin which could be used to suppress methanogenesis in the rumen ecosystem. Fermented rice straw (FRS) containing lovastatin after fermentation withAspergillus terreuswas used as substrate for growth study of rumen microorganisms usingin vitrogas production method. In the first experiment, the extract from the FRS (FRSE) which contained lovastatin was evaluated for its efficacy for reduction in methane (CH4) production, microbial population, and activity in the rumen fluid. FRSE reduced total gas and CH4productions (P<0.01). It also reduced (P<0.01) total methanogens population and increased the cellulolytic bacteria includingRuminococcus albus,Fibrobacter succinogenes(P<0.01), andRuminococcus flavefaciens(P<0.05). Similarly, FRS reduced total gas and CH4productions, methanogens population, but increasedin vitrodry mater digestibility compared to the non-fermented rice straw. Lovastatin in the FRSE and the FRS significantly increased the expression of HMG-CoA reductase gene that produces HMG-CoA reductase, a key enzyme for cell membrane production in methanogenic Archaea.
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Baker, S. K. "Rumen methanogens, and inhibition of methanogenesis". Australian Journal of Agricultural Research 50, nr 8 (1999): 1293. http://dx.doi.org/10.1071/ar99005.
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Methane-producing archaea (known as methanogens) are a distinct group of organisms which are a normal component of the rumen microbial ecosystem. Hydrogen and carbon dioxide are the principal substrates used by rumen methanogens to produce methane (CH4). Because hydrogen and formate are products of fermentation by other microorganisms in the rumen, inhibition of fermentation by other members of the rumen microbial population may in turn inhibit methanogenesis. As well, compounds that inhibit the activity of methanogens directly are likely to reduce or eliminate CH4 production. A strong inverse relationship between the molar proportion of propionate and CH4 production is predicted from knowledge of the interactions among microbial populations in the rumen, and compounds that promote greater production of propionate in the rumen may also have the effect of decreasing CH4 production. Although a wide range of ionophores, antibiotics, and other compounds have been evaluated in vivo and in vitro for their influence on rumen microbial populations and on propionate production, re-evaluation of some of these has been prompted by a search for compounds that both enhance propionate production and decrease production. Where there is a focus on CH4 production by livestock, interest necessarily is in the total amount of CH4 produced per day as a proportion of gross energy intake (%GEI) and its relationship with animal productivity. Because enhanced production of propionate in the rumen also can be associated with an increase in the flow of microbial protein from the rumen, evaluation or re-evaluation of compounds that may be effective in reducing methane production should also include evaluation of the effects on animal productivity, and appropriate approaches are discussed.
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Mavrommatis, Alexandros, Dimitrios Skliros, Marica Simoni, Federico Righi, Emmanouil Flemetakis i Eleni Tsiplakou. "Alterations in the Rumen Particle-Associated Microbiota of Goats in Response to Dietary Supplementation Levels of Schizochytrium spp." Sustainability 13, nr 2 (10.01.2021): 607. http://dx.doi.org/10.3390/su13020607.
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Fat rich microorganisms, such as microalgae Schizochytrium spp., are potential biotechnological tools in the modulation of rumen microbiome towards ecofriendly and high nutritional value end-products. However, limited in vivo trials have been reported on the topic. The aim of this study was to contribute to the knowledge on the effect of fat rich microalgae on the methanogenic and feed degrading particle-associated microbes in goats’ rumen content. For the trial, twenty-four goats were divided into four homogenous clusters (six goats/treatment) according to their fat corrected (4%) milk yield, body weight and age and individually were fed with alfalfa hay and concentrate feeds (F/C = 50/50). The concentrate of the control group (CON) contained no microalgae, while those of the treated groups were supplemented daily with 20 (ALG20), 40 (ALG40), and 60 (ALG60) g of Schizochytrium spp./goat. The relative abundances of total Archaea, methanogens, Methanomassiliicoccales, Methanobrevibacter spp., Methanosphaera stadmanae and Methanobacterium formicicum were significantly (p < 0.05) decreased in microalgae-fed goats compared to the CON ones. Moreover, a significant decline in the relative abundances of Firmicutes, Ruminococcus flavefaciens, Butyrivibrio fibrosolvents, and Neocallimastigales in the rumen particle-associated microbiota of microalgae supplemented goats were observed. In conclusion, goats’ diets supplementation with Schizochytrium spp., could be considered a sustainable nutritional strategy for methanogens inhibition in their rumen particle-associated microbiota.
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Mavrommatis, Alexandros, Dimitrios Skliros, Marica Simoni, Federico Righi, Emmanouil Flemetakis i Eleni Tsiplakou. "Alterations in the Rumen Particle-Associated Microbiota of Goats in Response to Dietary Supplementation Levels of Schizochytrium spp." Sustainability 13, nr 2 (10.01.2021): 607. http://dx.doi.org/10.3390/su13020607.
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Fat rich microorganisms, such as microalgae Schizochytrium spp., are potential biotechnological tools in the modulation of rumen microbiome towards ecofriendly and high nutritional value end-products. However, limited in vivo trials have been reported on the topic. The aim of this study was to contribute to the knowledge on the effect of fat rich microalgae on the methanogenic and feed degrading particle-associated microbes in goats’ rumen content. For the trial, twenty-four goats were divided into four homogenous clusters (six goats/treatment) according to their fat corrected (4%) milk yield, body weight and age and individually were fed with alfalfa hay and concentrate feeds (F/C = 50/50). The concentrate of the control group (CON) contained no microalgae, while those of the treated groups were supplemented daily with 20 (ALG20), 40 (ALG40), and 60 (ALG60) g of Schizochytrium spp./goat. The relative abundances of total Archaea, methanogens, Methanomassiliicoccales, Methanobrevibacter spp., Methanosphaera stadmanae and Methanobacterium formicicum were significantly (p < 0.05) decreased in microalgae-fed goats compared to the CON ones. Moreover, a significant decline in the relative abundances of Firmicutes, Ruminococcus flavefaciens, Butyrivibrio fibrosolvents, and Neocallimastigales in the rumen particle-associated microbiota of microalgae supplemented goats were observed. In conclusion, goats’ diets supplementation with Schizochytrium spp., could be considered a sustainable nutritional strategy for methanogens inhibition in their rumen particle-associated microbiota.
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Samal, L., L. C. Chaudhary, N. Agarwal i D. N. Kamra. "Effects of plants containing secondary metabolites as feed additives on rumen metabolites and methanogen diversity of buffaloes". Animal Production Science 56, nr 3 (2016): 472. http://dx.doi.org/10.1071/an15596.
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Four fistulated adult Murrah buffaloes were fed on a basal diet consisting of wheat straw and concentrate mixture in a 4 × 4 Latin square design to study the effects of feeding plants containing secondary metabolites on rumen metabolites and methanogen diversity. The four groups were Control (no additive), Mix-1 (ajwain oil and lemon grass oil in a 1 : 1 ratio @ 0.05% of dry matter intake), Mix-2 (garlic and soapnut in a 2 : 1 ratio @ 2% of dry matter intake) and Mix-3 (garlic, soapnut, harad and ajwain in a 2 : 1 : 1 : 1 ratio @ 1% of dry matter intake). In each phase of 30 days’ duration, after 19 days of feeding, rumen liquor was sampled for two consecutive days at 0, 2, 4, 6 and 8 h post-feeding, whereas rumen content was sampled at 0 h feeding. The pH of the rumen liquor was recorded at every collection and then the rumen liquor of every collection was pooled day-wise and animal-wise. These pooled samples were used for estimation of rumen metabolites like ammonia, lactic acid and volatile fatty acids. Microscopic counting of protozoa was done in both 0 h and pooled samples of rumen liquor. Rumen contents collected from different locations of rumen were processed for enzyme estimation. The rumen contents were squeezed and the liquid portion was used for DNA isolation, which was further processed to determine methanogen diversity. Daily intake of feed was similar (P > 0.05) in all the four groups. The ammonia-N concentration and ciliate protozoa population were reduced significantly in the treatment groups supplemented with additives. Rumen pH, lactic acid, volatile fatty acids and enzyme activities were not affected (P > 0.05) by feeding of any of these additives. Methanogenic diversity comparison was made between the Control and Mix-1 group. The basic local alignment search tool (BLAST) analysis of the 133 (44 from the Control group and 89 from the Mix-1 group) sequences showed similarity of the sequences of rumen archaea by up to 97% to the known sequences of rumen methanogens. The sequences with minimum length of 750 bp were selected for phylogenetic analysis. Per cent identity of these sequences with that of the available nearest neighbour as calculated by MEGA 5.03 software showed identity of the clones in the range of 88–97%. The clones were similar with Methanobrevibacter smithii ATCC 35061, uncultured Methanobrevibacter sp. clone MEME95 and M. ruminantium M1. Overall, feeding of any of these feed additives to fistulated buffaloes did not affect feed intake, rumen pH, or rumen metabolites except ammonia and enzyme profile. Methanogen diversity showed the possibility of Methanobrevibacter as the major methanogen in buffalo rumen liquor.
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Jonova, S., A. Ilgaza, M. Zolovs i A. Balins. "Impact of inulin and yeast containing synbiotic on calves' productivity and greenhouse gas production". June-2020 13, nr 6 (2020): 1017–24. http://dx.doi.org/10.14202/vetworld.2020.1017-1024.
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Aim: The research aimed to determine the impact of synbiotic: 6 g of prebiotic inulin and 5 g of probiotic Saccharomyces cerevisiae strain 1026 on calves' productivity and greenhouse gas (GHG) production. Materials and Methods: The research was conducted with 10 Holstein Friesian and Red Holstein (Bos taurus L.) crossbreed calves of mean age 33±6 days and initial body weight 73.4±12.75 kg. We added the synbiotic into the diet of five dairy crossbreed calves (SynG) and five calves in control group (CoG) received non-supplemented diet. The duration of the experiment was 56 days. The weight of calves and amount of methane (CH4) and carbon dioxide (CO2) in the rumen were determined on day 1, 28, and 56. On day 56, three calves from each group were slaughtered. Meat samples were assessed for some indicators of meat quality. The main methanogens were detected in the rumen fluid and feces. Results: The weight gain during the whole experiment period of 56 days was higher in the SynG (62.6±13.75 kg) compared to CoG (36.8±7.98 kg) calves (p<0.01). There were no significant differences in the levels of protein (%), fat (unsaturated and saturated – %), and cholesterol (mg/100 g) in meat samples from both groups. At the end of the experiment, the amount of CH4 in calves' rumen in CoG was higher (Me=792.06 mg/m3, interquartile range [IQR] 755.06-873.59) compared to SynG (Me=675.41 mg/m3, IQR 653.46-700.50) group (p<0.01). The values for CO2 were also increased in CoG (Me=4251.28 mg/m3, IQR 4045.58-4426.25) compared to SynG (Me=3266.06 mg/m3, IQR 1358.98-4584.91) group (p=0.001). There were no significant differences in the calves' weight and certain methanogen species in rumen liquid and feces on the 56th day of the experiment. Significantly higher results in the parameter total prokaryotes (V3) (bacteria+archaea) in rumen fluid were in SynG, whereas significantly higher results in the parameter total methanogens Met630/803 in rumen fluid were in CoG, p<0.05. Conclusion: The main results showed that the synbiotic can increase the daily weight gain in calves and decrease the amount of GHG in rumen but does not impact different methanogen species in rumen liquid and feces and meat protein, fat, and cholesterol levels.
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Jafari, Saeid, Yong M. Goh, Mohamed A. Rajion, Mahdi Ebrahimi i Mohammad F. Jahromi. "Dietary supplementation with papaya (Carica papaya L.) leaf affects abundance of rumen methanogens, fermentation characteristics and blood plasma fatty acid composition in goats". Spanish Journal of Agricultural Research 16, nr 2 (11.07.2018): e0607. http://dx.doi.org/10.5424/sjar/2018162-11812.
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The objective of this study was to test the effect of feeding papaya leaf (PL) on rumen microbial population, fermentation characteristics, blood fatty acid composition and antioxidant activity in goats. Three rumen fistulated male goats were assigned in a 3×3 latin square design using three levels of PL: no addition of PL in basal diet (control, CON, 50% concentrate + 50% alfalfa hay), 25% of alfalfa hay in basal diet replaced by PL (medium PL, MPL) and 50% of alfalfa hay in basal diet replaced by PL (high PL, HPL). Rumen fluid and blood plasma were sampled from the animals at the end of feeding trial (third week). Papaya leaf treatments (MPL and HPL) showed significant differences (p<0.05) in terms of rumen fermentation parameters as compared to the CON group at different times of measurement. The concentration of methanogenic archaea (log10cell/L) decreased (p<0.05) in both PL treatment groups as compared with CON group at all sampling times. The concentration of α-linolenic acid and total conjugated linoleic acid (CLA) were also higher (p<0.05) in the blood of goats fed PL especially HPL, compared to the CON. Blood plasma malondialdehyde concentration (mM/mL) of PL treatment groups showed a significant reduction as compared with CON. Supplementation of PL allowed the modulation of rumen characteristics which might represent a feeding strategy to reduce methane emission by directly inhibiting methanogens while improving the health benefits of ruminant products.
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Paul, Kristina, James O. Nonoh, Lena Mikulski i Andreas Brune. "“Methanoplasmatales,” Thermoplasmatales-Related Archaea in Termite Guts and Other Environments, Are the Seventh Order of Methanogens". Applied and Environmental Microbiology 78, nr 23 (21.09.2012): 8245–53. http://dx.doi.org/10.1128/aem.02193-12.
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ABSTRACTTheEuryarchaeotacomprise both methanogenic and nonmethanogenic orders and many lineages of uncultivated archaea with unknown properties. One of these deep-branching lineages, distantly related to theThermoplasmatales, has been discovered in various environments, including marine habitats, soil, and also the intestinal tracts of termites and mammals. By comparative phylogenetic analysis, we connected this lineage of 16S rRNA genes to a large clade of unknownmcrAgene sequences, a functional marker for methanogenesis, obtained from the same habitats. The identical topologies of 16S rRNA andmcrAgene trees and the perfect congruence of all branches, including several novel groups that we obtained from the guts of termites and cockroaches, strongly suggested that they stem from the same microorganisms. This was further corroborated by two highly enriched cultures of closely related methanogens from the guts of a higher termite (Cubitermes ugandensis) and a millipede (Anadenobolussp.), which represented one of the arthropod-specific clusters in the respective trees. Numerous other pairs of habitat-specific sequence clusters were obtained from the guts of other termites and cockroaches but were also found in previously published data sets from the intestinal tracts of mammals (e.g., rumen cluster C) and other environments. Together with the recently describedMethanomassiliicoccus luminyensisisolated from human feces, which falls into rice cluster III, the results of our study strongly support the idea that the entire clade of “unculturedThermoplasmatales” in fact represents the seventh order of methanogenic archaea, for which the provisional name “Methanoplasmatales” is proposed.
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Amokrane, Serine, Rabah Arhab, Serina Calabro, Raffaella Tudisco, Federico Infascelli i Moufida Aggoun. "Nutrient Content, in Vitro Ruminal Fermentation Characteristics and Antimethanogenic Potential of Three Algerian Asteraceae Species". Sultan Qaboos University Journal for Science [SQUJS] 25, nr 1 (9.06.2020): 10. http://dx.doi.org/10.24200/squjs.vol25iss1pp10-16.
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The in vitro rumen fermentation parameters and the antimethanogenic potential of three Asteraceae species: Chamaemelum nobile, Centaurea pulata and Chrysanthemum segetum were determined. Serum bottles containing 200 mg of each plant and 30 ml of the culture medium (artificial saliva plus rumen juice) were incubated for 24 h. After incubation, pH, volatile fatty acid (VFA), ammonia (NH3) and methane (CH4) productions were recorded. Methanogens and protozoa were quantified using a Real Time PCR technique (qPCR). Cumulative gas productions, in vitro organic matter digestibility and VFA were not significantly affected by the added species when compared to the control (P > 0.05). The effects of Chamaemelum nobile and Chrysanthemum segetum on methane production, NH3 and acetate to propionate ratio (C2:C3) were similar. The two species were able to modulate rumen fermentation to produce significantly lower CH4 concentrations (-24.3% and -27.1%, respectively) compared to the control. C.pulata produced the highest cumulative gas and stimulated the microbial metabolism with an increase in C2:C3 ratio, NH3 and methane production (P < 0.05). No significant effect of the three species on methanogenic Archaea and protozoa was registered (P > 0.05). The three species studied herein show a good potential for mitigating ruminal methane production without any undesirable effects on the main fermentation parameters.
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Nagaraja, T. G. "388 Nutrition and the Ruminal Microbiome: Emerging Frontiers from an Old Friend". Journal of Animal Science 98, Supplement_4 (3.11.2020): 171. http://dx.doi.org/10.1093/jas/skaa278.314.
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Abstract Rumen, a pregastric anaerobic gut ecosystem, inhabits arguably the most diverse and complex microbial community, with a mutualistic relationship with the host. The relationship is best exemplified in the utilization of lignocellulosic material and non-protein nitrogen to provide energy and protein to the host. The microbial community of the rumen is composed of bacteria, archaea, protozoa, fungi and bacteriophages. Culture- or microscopy-based procedures have identified over 200 species of bacteria, methanogens, ciliated protozoa and zoosporic fungi. The community analysis based on the genetic material of all microbial cells, called microbiome, has vastly expanded our understanding of the ruminal ecosystem. Microbiome analysis is based on sequencing of the targeted amplicons (16S rDNA variable regions for bacteria and archaea, 18S rDNA for protozoa or Internal Transcribed Regions for fungi) or whole genome shotgun metagenomics analysis. Rapid advancements in nucleic acid sequencing technologies and bioinformatics pipelines have provided unprecedented opportunities to delineate the diversity and complexity of the microbial community in relation ruminal function and dysfunctions and link ruminal microbes to host nutrition and productivity. Culture-independent methods have identified thousands of microbial species in the rumen, suggesting that a major fraction of the microbiome has not been cultured and functionally identified. A core microbiome in bacterial and archaeal populations of the rumen has been identified across a wide geographical regions, but significant variations in diversity, abundance, and individual taxa do exist because of diet and host genetics. However, there is evidence of signature microbiome among individual animals on the same diet and environment. Microbiome-wide association studies in relation to dietary changes, ruminal function and dysfunctions have begun to link and define the complexity of the host-microbe relationships. Translation of the potential of the microbiome analysis is supported by emerging evidences that specific microbiota can be linked to ruminal activity and productivity.
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Evans, Paul N., Lyn A. Hinds, Lindsay I. Sly, Christopher S. McSweeney, Mark Morrison i André-Denis G. Wright. "Community Composition and Density of Methanogens in the Foregut of the Tammar Wallaby (Macropus eugenii)". Applied and Environmental Microbiology 75, nr 8 (13.02.2009): 2598–602. http://dx.doi.org/10.1128/aem.02436-08.
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ABSTRACT The composition of the methanogenic archaeal community in the foregut contents of Tammar wallabies (Macropus eugenii) was studied using 16S rRNA and methyl coenzyme reductase subunit A (mcrA) gene clone libraries. Methanogens belonging to the Methanobacteriales and a well-supported cluster of uncultivated archaeon sequences previously observed in the ovine and bovine rumens were found. Methanogen densities ranged from 7.0 × 105 and 3.9 × 106 cells per gram of wet weight.
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Tajima, Kiyoshi, Takafumi Nagamine, Hiroki Matsui, Mutsumi Nakamura i Rustam I. Aminov. "Phylogenetic analysis of archaeal 16S rRNA libraries from the rumen suggests the existence of a novel group of archaea not associated with known methanogens". FEMS Microbiology Letters 200, nr 1 (czerwiec 2001): 67–72. http://dx.doi.org/10.1111/j.1574-6968.2001.tb10694.x.
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Machmüller, Andrea, Carla R. Soliva i Michael Kreuzer. "Methane-suppressing effect of myristic acid in sheep as affected by dietary calcium and forage proportion". British Journal of Nutrition 90, nr 3 (wrzesień 2003): 529–40. http://dx.doi.org/10.1079/bjn2003932.
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The efficiency of myristic acid (14:0) as a feed additive to suppress CH4emissions of ruminants was evaluated under different dietary conditions. Six sheep were subjected to a 6 × 6 Latin square arrangement. A supplement of non-esterified 14: 0 (50 g/kg DM) was added to two basal diets differing in their forage:concentrate values (1:1/5 and 1: 0/5), which were adjusted to dietary Ca contents of 4/2 and 9/0 g/ kg DM, respectively. Comparisons were made with the unsupplemented basal diets (4/2 g Ca/kg DM). The 14:0 supplementation decreased (P< 0/001) total tract CH4release depending on basal diet type (interaction,P< 0/001) and dietary Ca level (P< 0/05,post hoctest). In the concentrate-based diet, 14:0 suppressed CH4emission by 58 and 47% with 4/2 and 9/0 g Ca/kg DM, respectively. The 14:0 effect was lower (22%) in the forage-based diet and became insignificant with additional Ca. Myristic acid inhibited (P< 0/05) rumen archaea without significantly altering proportions of individual methanogen orders. Ciliate protozoa concentration was decreased (P< 0/05,post hoctest) by 14:0 only in combination with 9/0 g Ca/kg DM. Rumen fluid NH3concentration and acetate:pro-pionate were decreased (P< 0/05) and water consumption was lower (P< 0/01) with 14:0. The use of 14:0 had no clear effects on total tract organic matter and fibre digestion; this further illustrates that the suppressed methanogenesis resulted from direct effects against methanogens. The present study demonstrated that 14:0 is a potent CH4inhibitor but, to be effective in CH4mitigation feeding strategies, interactions with other diet ingredients have to be considered.
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Ilina, Larisa, Valentina Filippova, Elena Yildirim i Kasim Layshev. "Archaea in the microbial community of the reindeer rumen in the Russian Arctic". BIO Web of Conferences 27 (2020): 00066. http://dx.doi.org/10.1051/bioconf/20202700066.
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Archaea is the least studied group of the reindeer rumen microbiocenosis. Although the functional load performed by this group of microorganisms in the rumen is large. Methane-forming archaea play a key role in the process of anaerobic decomposition of organic substances, the formation of methane. This study for the first time analyzed the composition of the archaeal part of the microbial community of the reindeer rumen using the T-RFLP method from various regions of the Russian Arctic. As a result, it was found that according to the estimates of the number of archaea by quantitative PCR in the reindeer rumen in the winter-spring period, on average, 108 genomes/g of archaea were observed in individuals of the Yamalo-Nenets Autonomous District, and 109 genomes/in animals from the Nenets Autonomous District Archean. Thus, in the winter-spring period, a lower number of archaea in the rumen was observed in the Yamalo-Nenets Autonomous District. According to the results of the T-RFLP method, 44 to 134 phylotypes were detected in the archaeal community of the reindeer rumen, the Shannon index was 2.02–3.80. The lowest content (up to 11.10 %) of methanogenic archaea of the Methanomicrobia class (including the families Methanosarcinaceae and Methanocorpusculaceae) was revealed in the Nenets Autonomous District, while their presence in individuals of the Yamalo-Nenets Autonomous District reached 36.33 %. Interestingly, in adults of the Yamalo-Nenets and Nenets Autonomous Districts, a significant decrease in the representation of methanogenic archaea of the Methanomicrobia class was noted by 1.38 (P <0.05) and 2.70 times (P <0.01), respectively, compared with young individuals (up to 2 years).
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Seedorf, Henning, Sandra Kittelmann i Peter H. Janssen. "Few Highly Abundant Operational Taxonomic Units Dominate within Rumen Methanogenic Archaeal Species in New Zealand Sheep and Cattle". Applied and Environmental Microbiology 81, nr 3 (21.11.2014): 986–95. http://dx.doi.org/10.1128/aem.03018-14.
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ABSTRACTSequencing and analyses of 16S rRNA gene amplicons were performed to estimate the composition of the rumen methanogen community in 252 samples from eight cohorts of sheep and cattle, separated into 16 different sample groups by diet, and to determine which methanogens are most prominent in the rumens of farmed New Zealand ruminants.Methanobacteriales(relative abundance ± standard deviation, 89.6% ± 9.8%) andMethanomassiliicoccales(10.4% ± 9.8%) were the two major orders and contributed 99.98% (±0.1%) to the rumen methanogen communities in the samples. Sequences fromMethanobacterialeswere almost entirely from only four different species (or clades of very closely related species). Each was detectable in at least 89% of the samples. These four species or clades were theMethanobrevibacter gottschalkiiclade andMethanobrevibacter ruminantiumclade with a mean abundance of 42.4% (±19.5% standard deviation) and 32.9% (±18.8%), respectively, andMethanosphaerasp. ISO3-F5 (8.2% ± 6.7%) andMethanosphaerasp. group5 (5.6% ± 5.7%). These four species or clades appeared to be primarily represented by only one or, in one case, two dominant sequence types per species or clade when the sequences were grouped into operational taxonomic units (OTUs) at 99% sequence identity. The mean relative abundance ofMethanomassiliicoccalesin the samples was relatively low but exceeded 40% in some of the treatment groups. Animal feed affected the apparent methanogen community structure of both orders, as evident from differences in relative abundances of the major OTUs in animals under different feeding regimens.
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Tymensen, Lisa D., i Tim A. McAllister. "Community Structure Analysis of Methanogens Associated with Rumen Protozoa Reveals Bias in Universal Archaeal Primers". Applied and Environmental Microbiology 78, nr 11 (23.03.2012): 4051–56. http://dx.doi.org/10.1128/aem.07994-11.
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ABSTRACTThe diversity of protozoan-associated methanogens in cattle was investigated using five universal archaeal small-subunit (SSU) rRNA gene primer sets.Methanobrevibacterspp. and rumen cluster C (distantly related toThermoplasmaspp.) were predominant. Significant differences in species composition among libraries indicate that some primers used previously to characterize rumen methanogens exhibit biased amplification.
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Attwood, G. T., W. J. Kelly, E. H. Altermann, C. D. Moon, S. Leahy i A. L. Cookson. "Application of rumen microbial genome information to livestock systems in the postgenomic era". Australian Journal of Experimental Agriculture 48, nr 7 (2008): 695. http://dx.doi.org/10.1071/ea07408.
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Sequencing the genomes of individual rumen microbes and determining the function of their encoded genes promises to transform our understanding of the microbiology of the rumen. The diversity and density of microbes in the rumen, and our inability to culture the majority of rumen microbes, limit current genome studies to only a small fraction of the microbes present in this environment. Nevertheless, genomes of fibre-degrading organisms are beginning to reveal a previously unexpected abundance of genes encoding glycosyl hydrolases and carbohydrate esterases, which could be used to enhance fibre digestion in the rumen. Additionally, genome sequencing of a rumen methanogen is identifying conserved genes within the methanogenic archaea that may serve as targets for their inhibition and therefore reduction of methane emissions from ruminants. The problem of rumen microbe culturability can be overcome by a new approach called metagenomics, in which microbial DNAs are extracted from rumen samples and sequenced independent of cultivation. In the future, sequencing individual genomes and metagenomic libraries is likely to capture much more of the microbial DNA in the rumen and, coupled with postgenomic studies on gene and protein expression, is likely to enhance our knowledge of the microbial component of ruminant digestion.
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Raizada, N., V. Sonakya, R. Dalhoff, M. Hausner i P. A. Wilderer. "Population dynamics of rumen microbes using modern techniques in rumen enhanced solid incubation". Water Science and Technology 48, nr 4 (1.08.2003): 113–19. http://dx.doi.org/10.2166/wst.2003.0234.
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The microbial ecology of the rumen is very complex. Different species of bacteria, protozoa, and fungi are involved in digestion of plant material in ruminants. In spite of complicated interrelationships among the various groups of microorganisms in the rumen ecosystem, Bacteria and Archaea are believed to play a major role because of their numerical predominance and metabolic diversity. In this work we are presenting the results for microbial population dynamics of rumen microbes during two-stage anaerobic digestion of grass. The reactors were inoculated with fresh rumen content. Fluorescent in situ hybridization, confocal laser scanning microscopy and epifluorescence microscopy were employed for microbial investigation. It was observed that Bacteria dominated in the hydrolytic reactor (1st stage) whereas Archaea were predominant in the methanogenic reactor (2nd stage). The stability of the methanogenic reactor was result of the dominance of Methanosaeta species (mainly the filamentous type).
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King, Erin E., Rachel P. Smith, Benoit St-Pierre i André-Denis G. Wright. "Differences in the Rumen Methanogen Populations of Lactating Jersey and Holstein Dairy Cows under the Same Diet Regimen". Applied and Environmental Microbiology 77, nr 16 (24.06.2011): 5682–87. http://dx.doi.org/10.1128/aem.05130-11.
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ABSTRACTIn the dairy cattle industry, Holstein and Jersey are the breeds most commonly used for production. They differ in performance by various traits, such as body size, milk production, and milk composition. With increased concerns about the impact of agriculture on climate change, potential differences in other traits, such as methane emission, also need to be characterized further. Since methane is produced in the rumen by methanogenic archaea, we investigated whether the population structure of methanogen communities would differ between Holsteins and Jerseys. Breed-specific rumen methanogen 16S rRNA gene clone libraries were constructed from pooled PCR products obtained from lactating Holstein and Jersey cows, generating 180 and 185 clones, respectively. The combined 365 sequences were assigned to 55 species-level operational taxonomic units (OTUs). Twenty OTUs, representing 85% of the combined library sequences, were common to both breeds, while 23 OTUs (36 sequences) were found only in the Holstein library and 12 OTUs (18 sequences) were found only in the Jersey library, highlighting increased diversity in the Holstein library. Other differences included the observation that sequences with species-like sequence identity toMethanobrevibacter milleraewere represented more highly in the Jersey breed, whileMethanosphaera-related sequences and novel uncultured methanogen clones were more frequent in the Holstein library. In contrast, OTU sequences with species-level sequence identity toMethanobrevibacter ruminantiumwere represented similarly in both libraries. Since the sampled animals were from a single herd consisting of two breeds which were fed the same diet and maintained under the same environmental conditions, the differences we observed may be due to differences in host breed genetics.
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Chagan, Irbis, Mitsunori Tokura, Jean-Pierre Jouany i Kazunari Ushida. "Detection of methanogenic archaea associated with rumen ciliate protozoa." Journal of General and Applied Microbiology 45, nr 6 (1999): 305–8. http://dx.doi.org/10.2323/jgam.45.305.
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Huang, Xiao Dan, Gonzalo Martinez-Fernandez, Jagadish Padmanabha, Ruijun Long, Stuart E. Denman i Christopher S. McSweeney. "Methanogen Diversity in Indigenous and Introduced Ruminant Species on the Tibetan Plateau". Archaea 2016 (2016): 1–10. http://dx.doi.org/10.1155/2016/5916067.
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Host factors are regarded as important in shaping the archaeal community in the rumen but few controlled studies have been performed to demonstrate this across host species under the same environmental conditions. A study was designed to investigate the structure of the methanogen community in the rumen of two indigenous (yak and Tibetan sheep) and two introduced domestic ruminant (cattle and crossbred sheep) species raised and fed under similar conditions on the high altitude Tibetan Plateau. The methylotrophic Methanomassiliicoccaceae was the predominant archaeal group in all animals even thoughMethanobrevibacterare usually present in greater abundance in ruminants globally. Furthermore, within the Methanomassiliicoccaceae family members fromMmc.group 10 andMmc.group 4 were dominant in Tibetan Plateau ruminants compared toMmc.group 12 found to be highest in other ruminants studied. Small ruminants presented the highest number of sequences that belonged to Methanomassiliicoccaceae compared to the larger ruminants. Although the methanogen community structure was different among the ruminant species, there were striking similarities between the animals in this environment. This indicates that factors such as the extreme environmental conditions and diet on the Tibetan Plateau might have a greater impact on rumen methanogen community compared to host differences.
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Torok, Valeria A., Nigel J. Percy, Peter J. Moate i Kathy Ophel-Keller. "Influence of dietary docosahexaenoic acid supplementation on the overall rumen microbiota of dairy cows and linkages with production parameters". Canadian Journal of Microbiology 60, nr 5 (maj 2014): 267–75. http://dx.doi.org/10.1139/cjm-2013-0805.
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The rumen microbiota contributes to greenhouse gas emissions and has an impact on feed efficiency and ruminant product fatty acid composition. Dietary fat supplements have shown promise in reducing enteric methane production and in altering the fatty acid profiles of ruminant-derived products, yet in vivo studies on how these impact the rumen microbiota are limited. In this study, we investigated the rumen bacterial, archaeal, fungal, and ciliate protozoan communities of dairy cows fed diets supplemented with 4 levels of docosahexaenoic acid (DHA) (0, 25, 50, and 75 g·cow−1·day−1) and established linkages between microbial communities and production parameters. Supplementation with DHA significantly (P < 0.05) altered rumen bacterial and archaeal, including methanogenic archaeal, communities but had no significant (P > 0.05) effects on rumen fungal or ciliate protozoan communities. Rumen bacterial communities of cows receiving no DHA were correlated with increased saturated fatty acids (C18:0 and C11:0) in their milk. Furthermore, rumen bacterial communities of cows receiving a diet supplemented with 50 g DHA·cow−1·day−1 were correlated with increases in monounsaturated fatty acids (C20:1n-9) and polyunsaturated fatty acids (C22:5n-3; C22:6n-3; C18:2 cis-9, trans-11; C22:3n-6; and C18:2n-6 trans) in their milk. The significant diet-associated changes in rumen archaeal communities observed did not result in altered enteric methane outputs in these cows.
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Kong, Yunhong, Maolong He, Tim McAlister, Robert Seviour i Robert Forster. "Quantitative Fluorescence In Situ Hybridization of Microbial Communities in the Rumens of Cattle Fed Different Diets". Applied and Environmental Microbiology 76, nr 20 (27.08.2010): 6933–38. http://dx.doi.org/10.1128/aem.00217-10.
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ABSTRACT At present there is little quantitative information on the identity and composition of bacterial populations in the rumen microbial community. Quantitative fluorescence in situ hybridization using newly designed oligonucleotide probes was applied to identify the microbial populations in liquid and solid fractions of rumen digesta from cows fed barley silage or grass hay diets with or without flaxseed. Bacteroidetes, Firmicutes, and Proteobacteria were abundant in both fractions, constituting 31.8 to 87.3% of the total cell numbers. They belong mainly to the order Bacteroidales (0.1 to 19.2%), hybridizing with probe BAC1080; the families Lachnospiraceae (9.3 to 25.5%) and Ruminococcaceae (5.5 to 23.8%), hybridizing with LAC435 and RUM831, respectively; and the classes Deltaproteobacteria (5.8 to 28.3%) and Gammaproteobacteria (1.2 to 8.2%). All were more abundant in the rumen communities of cows fed diets containing silage (75.2 to 87.3%) than in those of cows fed diets containing hay (31.8 to 49.5%). The addition of flaxseed reduced their abundance in the rumens of cows fed silage-based diets (to 45.2 to 58.7%) but did not change markedly their abundance in the rumens of cows fed hay-based diets (31.8 to 49.5%). Fibrolytic species, including Fibrobacter succinogenes and Ruminococcus spp., and archaeal methanogens accounted for only a small proportion (0.4 to 2.1% and 0.2 to 0.6%, respectively) of total cell numbers. Depending on diet, between 37.0 and 91.6% of microbial cells specifically hybridized with the probes used in this study, allowing them to be identified in situ. The identities of other microbial populations (8.4 to 63.0%) remain unknown.
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Gill, F. L., R. D. Pancost, I. D. Bull, E. McGeough, P. O'Kiely i R. J. Dewhurst. "Investigation of faecal archaeol as a biomarker for rumen methanogens". Advances in Animal Biosciences 1, nr 1 (kwiecień 2010): 48. http://dx.doi.org/10.1017/s2040470010001913.
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Abecia, Leticia, Kate E. Waddams, Gonzalo Martínez-Fernandez, A. Ignacio Martín-García, Eva Ramos-Morales, C. Jamie Newbold i David R. Yáñez-Ruiz. "An Antimethanogenic Nutritional Intervention in Early Life of Ruminants Modifies Ruminal Colonization by Archaea". Archaea 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/841463.
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The aim of this work was to study whether feeding a methanogen inhibitor from birth of goat kids and their does has an impact on the archaeal population colonizing the rumen and to what extent the impact persists later in life. Sixteen goats giving birth to two kids were used. Eight does were treated (D+) with bromochloromethane after giving birth and over 2 months. The other 8 goats were not treated (D−). One kid per doe in both groups was treated with bromochloromethane (k+) for 3 months while the other was untreated (k−), resulting in four experimental groups: D+/k+, D+/k−, D−/k+, and D−/k−. Rumen samples were collected from kids at weaning and 1 and 4 months after (3 and 6 months after birth) and from does at the end of the treating period (2 months). Pyrosequencing analyses showed a modified archaeal community composition colonizing the rumen of kids, although such effect did not persist entirely 4 months after; however, some less abundant groups remained different in treated and control animals. The different response on the archaeal community composition observed between offspring and adult goats suggests that the competition occurring in the developing rumen to occupy different niches offer potential for intervention.
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Sundset, Monica A., Joan E. Edwards, Yan Fen Cheng, Roberto S. Senosiain, Maria N. Fraile, Korinne S. Northwood, Kirsti E. Praesteng, Trine Glad, Svein D. Mathiesen i André-Denis G. Wright. "Rumen microbial diversity in Svalbard reindeer, with particular emphasis on methanogenic archaea". FEMS Microbiology Ecology 70, nr 3 (grudzień 2009): 553–62. http://dx.doi.org/10.1111/j.1574-6941.2009.00750.x.
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Yáñez-Ruiz, D. R., K. J. Hart, A. I. Martin-Garcia, S. Ramos i C. J. Newbold. "Diet composition at weaning affects the rumen microbial population and methane emissions by lambs". Australian Journal of Experimental Agriculture 48, nr 2 (2008): 186. http://dx.doi.org/10.1071/ea07237.
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The aim of this experiment was to investigate whether different diets at weaning determine the microbial populations established in the rumen, together with its methanogenic capacity, and whether these differences are consistent over a longer time period. Twenty ewes with single lambs were used in two periods. Period I: 10 lambs had access only to grass hay whilst with the dam and for 8 weeks after weaning (group H). The other 10 lambs had free access to concentrate and grass hay whilst with the dam and were fed with a 60 : 40 mix of concentrate and grass hay for 8 weeks after weaning (group C). Eight weeks after weaning, methane emissions were measured in polycarbonate chambers over a 3-day period. After methane emission measurements, five lambs from each group were randomly selected and slaughtered and samples of rumen content collected for measuring rumen fermentation parameters and for microbial enumeration (total and cellulolytic bacteria and methanogenic archeaea) by most probable number. Period II: the remaining 10 lambs were grouped together and fed the same diet (grass and concentrate) for 4 months. After this period, all animals were fed concentrate and grass hay (60 : 40) for 2 weeks and introduced in to the chambers to measure methane emissions over a 3-day period. After measurements, they were slaughtered and rumen samples collected and analysed as in Period I. Lambs from group H produced more (P = 0.04) methane than group C lambs (26.0 v. 22.5 L/kg DM intake) in Period I. Group H lambs also had less total bacteria (10.2 × 1010 v. 61.6 × 1010 cells; P = 0.284) but more cellulolytic bacteria (40.6 × 109 v. 10.0 × 109 cells; P = 0.098) and methanogenic archaea (37.1 × 109 v. 19.0 × 109 cells; P = 0.113) than group C lambs in Period I. The acetate to propionate ratio tended to be higher (P = 0.089) in group H lambs than in group C lambs (3.00 v. 2.35). In Period II, methane produced was not different (P > 0.05) between the groups (26.6. v. 25.7 L/kg DM intake by group C and H lambs, respectively). Microbial numbers and fermentation parameters were also similar in samples collected from both experimental groups in Period II. Our results show that the differences observed as a result of providing different diets at weaning disappear in the long-term. It may be appropriate to study a wider range of dietary treatments to better understand the factors determining the microbial populations establishing in the rumen.
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GU, Min-Jung, Md Jahangir ALAM, Seon-Ho KIM, Che-Ok JEON, Moon-Baek CHANG, Young-Kyoon OH, Sang-Cheol LEE i Sang-Suk LEE. "Analysis of methanogenic archaeal communities of rumen fluid and rumen particles from Korean black goats". Animal Science Journal 82, nr 5 (15.06.2011): 663–72. http://dx.doi.org/10.1111/j.1740-0929.2011.00890.x.
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Eom, Jun Sik, Shin Ja Lee, Yejun Lee, Hyun Sang Kim, You Young Choi, Hyeong Suk Kim, Do Hyung Kim i Sung Sill Lee. "Effects of supplementation levels of Allium fistulosum L. extract on in vitro ruminal fermentation characteristics and methane emission". PeerJ 8 (27.08.2020): e9651. http://dx.doi.org/10.7717/peerj.9651.
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Background Ruminants release the majority of agricultural methane, an important greenhouse gas. Different feeds and additives are used to reduce emissions, but each has its drawbacks. This experiment was conducted to determine the effects of Allium fistulosum L. (A. fistulosum) extract on in vitro ruminal fermentation characteristics, and on methane emission. Methods Rumen fluid was taken from two cannulated rumen Hanwoo cow (with mean initial body weight 450 ± 30 kg, standard deviation = 30). Rumen fluid and McDougall’s buffer (1:2; 15 mL) were dispensed anaerobically into 50 mL serum bottles containing 300 mg (DM basis) of timothy substrate and A. fistulosum extracts (based on timothy substrate; 0%, 1%, 3%, 5%, 7%, or 9%). This experiment followed a completely randomized design performed in triplicate, using 126 individual serum bottles (six treatments × seven incubation times × three replicates). Results Dry matter degradability was not significantly affected (p-value > 0.05) by any A. fistulosum treatment other than 1% extract at 24 h incubation. Methane emission linearly decreased A. fistulosum extract concentration increased at 12 and 24 h incubation (p-value < 0.0001; p-value = 0.0003, respectively). Acetate concentration linearly decreased (p-value = 0.003) as A. fistulosum extract concentration increased at 12 h incubation. Methanogenic archaea abundance tendency decreased (p-value = 0.055) in the 1%, 7%, and 9% A. fistulosum extract groups compared to that in the 0% group, and quadratically decreased (p-value < 0.0001) as A. fistulosum extract concentration increased at 24 h incubation. Conclusion A. fistulosum extract had no apparent effect on ruminal fermentation characteristics or dry matter degradability. However, it reduced methane emission and methanogenic archaea abundance.
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Bharathi, M., i P. Chellapandi. "Intergenomic evolution and metabolic cross-talk between rumen and thermophilic autotrophic methanogenic archaea". Molecular Phylogenetics and Evolution 107 (luty 2017): 293–304. http://dx.doi.org/10.1016/j.ympev.2016.11.008.
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Firkins, J. L., S. K. R. Karnati i Z. Yu. "Linking rumen function to animal response by application of metagenomics techniques". Australian Journal of Experimental Agriculture 48, nr 7 (2008): 711. http://dx.doi.org/10.1071/ea08028.
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Metagenomics techniques applied to the rumen microbiota have demonstrated tremendous diversity originally among populations of bacteria and, more recently, among the methanogenic archaea, including those associated with protozoa. Although with some potential limitations, cluster analyses of sequences recovered from clone libraries have revealed differences in populations among animals fed forage v. grain, including amylolytic ruminococci and novel groups of clostridia adhering to the rumen particulates. Rapid profiling procedures, such as denaturing gradient gel electrophoresis (DGGE), can be used to infer likely differences in community structure of bacteria and archaea among numerous replicates of animals and times after feeding diets that are more representative of intense ruminant animal production. Metagenomics procedures also are being applied to issues related to ruminal output of fatty acid isomers influencing milk fat composition and consumer acceptance, the environmental impact of nitrogen in animal waste and methane emissions, and future potential approaches to improve ruminal fibre digestibility. If varying concentrations of ruminal metabolites and fluxes quantified from microbial processes can be combined with results from metagenomics applied to rumen microbiota, then we should reduce the unexplained variability in models in which the prediction of nutrient supply to the intestine is synchronised with nutritional guidelines for more efficient feed conversion by ruminants.
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Díaz Carrasco, Juan María, Claudio Cabral, Leandro Martín Redondo, Natalia Daniela Pin Viso, Darío Colombatto, Marisa Diana Farber i Mariano Enrique Fernández Miyakawa. "Impact of Chestnut and Quebracho Tannins on Rumen Microbiota of Bovines". BioMed Research International 2017 (2017): 1–11. http://dx.doi.org/10.1155/2017/9610810.
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The use of phytogenic dietary additives is being evaluated as a means to improve animal productivity. The effect of tannins seems to be the influence not only directly on the digestive process through binding of dietary proteins but also indirectly over their effects on gastrointestinal microbiota. High-throughput sequencing of 16S rRNA gene was used to analyze the impact of dietary supplementation with a blend of chestnut and quebracho tannins on the rumen microbiota of Holstein steers. Bacterial richness was lower in tannins treated animals, while the overall population structure of rumen microbiota was not significantly disturbed by tannins. The ratio of the phyla Firmicutes and Bacteroidetes, a parameter associated with energy harvesting function, was increased in tannins supplemented animals, essentially due to the selective growth of Ruminococcaceae over members of genusPrevotella. Fibrolytic, amylolytic, and ureolytic bacterial communities in the rumen were altered by tannins, while methanogenic archaea were reduced. Furthermore, ruminal pH was significantly higher in animals supplemented with tannins than in the control group, while urease activity exhibited the opposite pattern. Further work is necessary to assess the relation between tannins impact on rumen microbiota and alteration of rumen fermentation parameters associated with bovine performance.
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Newbold, C. J., K. Ushida, B. Morvan, G. Fonty i J. P. Jouany. "The role of ciliate protozoa in the lysis of methanogenic archaea in rumen fluid". Letters in Applied Microbiology 23, nr 6 (grudzień 1996): 421–25. http://dx.doi.org/10.1111/j.1472-765x.1996.tb01350.x.
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Lee, Hyo Jung, Ji Young Jung, Young Kyoon Oh, Sang-Suk Lee, Eugene L. Madsen i Che Ok Jeon. "Comparative Survey of Rumen Microbial Communities and Metabolites across One Caprine and Three Bovine Groups, Using Bar-Coded Pyrosequencing and1H Nuclear Magnetic Resonance Spectroscopy". Applied and Environmental Microbiology 78, nr 17 (15.06.2012): 5983–93. http://dx.doi.org/10.1128/aem.00104-12.
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ABSTRACTPyrosequencing of 16S rRNA genes (targetingBacteriaandArchaea) and1H nuclear magnetic resonance were applied to investigate the rumen microbiota and metabolites of Hanwoo steers in the growth stage (HGS), Hanwoo steers in the late fattening stage (HFS), Holstein-Friesian dairy cattle (HDC), and Korean native goats (KNG) in the late fattening stage. This was a two-part investigation. We began by comparing metabolites and microbiota of Hanwoo steers at two stages of husbandry. Statistical comparisons of metabolites and microbial communities showed no significant differences between HFS and HGS (differing by a dietary shift at 24 months and age [67 months versus 12 months]). We then augmented the study by extending the investigation to HDC and KNG. Overall, pyrosequencing of 16S rRNA genes showed that the rumens had highly diverse microbial communities containing many previously undescribed microorganisms. Bioinformatic analysis revealed that the bacterial sequences were predominantly affiliated with four phyla—Bacteroidetes,Firmicutes,Fibrobacteres, andProteobacteria—in all ruminants. However, interestingly, the bacterial reads belonging toFibrobactereswere present at a very low abundance (<0.1%) in KNG. Archaeal community analysis showed that almost all of these reads fell into a clade related to, but distinct from, known cultivated methanogens. Statistical analyses showed that the microbial communities and metabolites of KNG were clearly distinct from those of other ruminants. In addition, bacterial communities and metabolite profiles of HGS and HDC, fed similar diets, were distinctive. Our data indicate that bovine host breeds override diet as the key factor that determines bacterial community and metabolite profiles in the rumen.
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Nunez, Corina, Sara M. Tondini, Thomas G. Jennings, Justin W. Rickard, Angela R. Green-Miller, Daniel W. Shike, Darren D. Henry i Joshua C. McCann. "PSI-24 Relationship between passage rate and in vitro methane production from rumen and fecal contents". Journal of Animal Science 97, Supplement_2 (lipiec 2019): 240–41. http://dx.doi.org/10.1093/jas/skz122.423.
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Abstract The objective was to evaluate treatments designed to increase passage rate on the in vitro methanogenic potential of rumen and fecal contents. Eight ruminal-cannulated steers were used in a replicated 4×4 Latin square design with data collected from the latter three 24 d periods. All steers were fed an ad libitum diet of grass hay (10.4% CP) with the following treatments designed to increase passage rate: negative control (CON), pelleted (PEL), 7% Ca(OH)2 treated (CAOH), and four 6 kg weights added to the rumen (WTS). Molasses (3% of diet DM) was added to all treatments to improve diet palatability. On d 22 of each period, fecal and rumen samples for in vitro procedure were collected 0 and 2 hr after feeding, respectively. Rumen (10 g) and fecal (20 g) samples were added to 100 ml Wheaton vials with buffer solution at 1:5 and 1:2 ratio, respectively. Vials were incubated at 39°C, and samples were collected at 6 and 24 hr to determine gas production. Methane was analyzed using gas chromatography. Data were analyzed using the MIXED procedure of SAS. In vitro methane production rate from rumen samples tended (P = 0.09) to be affected by treatment with the greatest rate observed for CON (11.7 mM per g DM per h) and the least for PEL (6.3 mM per g DM per h). Rate of fecal methane production in vitro was not affected (P = 0.48) by treatment with means ranging from 0.79 to 2.3 mM per g DM per h. Predicted daily methane production from fecal dry matter excretion was also not affected (P = 0.98) by treatment. Treatments designed to increase passage rate may affect the methanogenic potential of archaea in ruminal contents but not in feces.
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Khejornsar, Pichad, i Metha Wanapat. "Diversity of Rumen Anaerobic Fungi and Methanogenic Archaea in Swamp Buffalo Influenced by Various Diets". Journal of Animal and Veterinary Advances 9, nr 24 (1.12.2010): 3062–69. http://dx.doi.org/10.3923/javaa.2010.3062.3069.
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Chaudhary, P. Prashant, S. Kumar Sirohi i S. Kumar. "Improved Extraction of Quality DNA from Methanogenic Archaea Present in Rumen Liquor for PCR Application". Asian Journal of Animal Sciences 5, nr 3 (15.04.2011): 166–74. http://dx.doi.org/10.3923/ajas.2011.166.174.
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Noel, Samantha J., Dana W. Olijhoek, Farran Mclean, Peter Løvendahl, Peter Lund i Ole Højberg. "Rumen and Fecal Microbial Community Structure of Holstein and Jersey Dairy Cows as Affected by Breed, Diet, and Residual Feed Intake". Animals 9, nr 8 (29.07.2019): 498. http://dx.doi.org/10.3390/ani9080498.
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Identifying factors that influence the composition of the microbial population in the digestive system of dairy cattle will be key in regulating these populations to reduce greenhouse gas emissions. In this study, we analyzed rumen and fecal samples from five high residual feed intake (RFI) Holstein cows, five low RFI Holstein cows, five high RFI Jersey cows and five low RFI Jersey cows, fed either a high-concentrate diet (expected to reduce methane emission) or a high-forage diet. Bacterial communities from both the rumen and feces were profiled using Illumina sequencing on the 16S rRNA gene. Rumen archaeal communities were profiled using Terminal-Restriction Fragment Length Polymorphism (T-RFLP) targeting the mcrA gene. The rumen methanogen community was influenced by breed but not by diet or RFI. The rumen bacterial community was influenced by breed and diet but not by RFI. The fecal bacterial community was influenced by individual animal variation and, to a lesser extent, by breed and diet but not by RFI. Only the bacterial community correlated with methane production. Community differences seen in the rumen were reduced or absent in feces, except in the case of animal-to-animal variation, where differences were more pronounced. The two cattle breeds had different levels of response to the dietary intervention; therefore, it may be appropriate to individually tailor methane reduction strategies to each cattle breed.
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Fagundes, Gisele M., Gabriela Benetel, Mateus M. Carriero, Ricardo L. M. Sousa, James P. Muir, Robert O. Macedo i Ives C. S. Bueno. "Tannin-rich forage as a methane mitigation strategy for cattle and the implications for rumen microbiota". Animal Production Science 61, nr 1 (2021): 26. http://dx.doi.org/10.1071/an19448.
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Context Methane from ruminant livestock systems contributes to the greenhouse effect on the environment, which justifies the adoption of novel feed strategies that mitigate enteric emissions. Aims We investigated the effects of the condensed tannin (CT)-rich legumes Flemingia macrophylla, Leucaena leucocephala, Stylosanthes guianensis, Gliricidia sepium, Cratylia argentea, Cajanus cajan, Desmodium ovalifolium, Macrotyloma axillare, Desmodium paniculatum and Lespedeza procumbens on in vitro methane emissions and rumen microbiota for beef cattle. Methods Four rumen-cannulated Nellore cattle grazing a tropical grass pasture were used as inoculum donors. Key results Real-time quantitative polymerase chain reaction analysis revealed that the abundance of Ruminococcus flavefaciens, methanogenic archaea and protozoa populations were reduced (P £ 0.05), whereas total ruminal bacteria were enhanced in the presence of CT. Our study also revealed a positive (P £ 0.05) relationship between CT and Fibrobacter succinogenes abundance. Reactive CT from L. leucocephala, D. paniculatum and L. procumbens resulted in decreased (P £ 0.05) isoacid content and methane production. Conclusions L. leucocephala, D. paniculatum and L. procumbens have the potential to suppress rumen methanogenesis. However, in vitro fermentation of L. leucocephala resulted in greater (P £ 0.05) degradability percentages than the other two species. Implications CT in legume species will have potential as part of an overall nutritional strategy to manipulate rumen microbiota and mitigate enteric methanogenesis in livestock production systems.
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Firkins, Jeffrey Lynn. "Reconsidering rumen microbial consortia to enhance feed efficiency and reduce environmental impact of ruminant livestock production systems". Revista Brasileira de Zootecnia 39, suppl spe (lipiec 2010): 445–57. http://dx.doi.org/10.1590/s1516-35982010001300049.
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Because cultivation-based approaches to assess rumen microbiology assess only the minority of microbial groups and can miss opportunities to assess important functions, molecular-based approaches have flourished in microbial ecology and have been adapted to the rumen. Current approaches are described herein, specifically for a robust adaptation to nutrition studies or future opportunities. These included automated profiling techniques, density gradient gel electrophoresis, and future adaption of microarray or high-throughput sequencing technologies. Based on current knowledge, a more holistic approach is needed to describe various functional groups of microbes within the context of how they influence, and are influenced by, the whole consortium (combination of microbial groups). Such a perspective is applied to issues related to increasing fiber digestibility when feeding concentrate or unsaturated fats to high producing beef and dairy cattle. These same microbial populations should help to provide growth factors for fibrolytic bacteria while competing against the hyperammonia-producing bacteria such that there would be less need for excessive rumen-degraded protein as a safety factor. Moreover, these same dietary conditions influence the processes of biohydrogenation and methanogenesis. After accounting for population structures of bacteria, protozoa, methanogenic archaea, and even fungi, efforts to integrate molecular-based rumen microbial ecology with dietary conditions should allow us to better explain and therefore predict conditions that will improve feed efficiency and reduce environmental impact of ruminant production systems.
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Boadi, D., C. Benchaar, J. Chiquette i D. Massé. "Mitigation strategies to reduce enteric methane emissions from dairy cows: Update review". Canadian Journal of Animal Science 84, nr 3 (1.09.2004): 319–35. http://dx.doi.org/10.4141/a03-109.
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Enteric methane (CH4) emission is a major contributor to Canadian greenhouse gas emissions, and also a loss of feed energy during production. The objective of this paper is to provide an update on current management practices and new dietary strategies recently proposed to reduce CH4 emissions from ruminants. Existing mitigation strategies for dairy, e.g., the addition of ionophores, fats, use of high-quality forages, and increased use of grains, have been well researched and applied. These nutritional changes reduce CH4 emissions by manipulating ruminal fermentation, directly inhibiting methanogens and protozoa, or by diverting hydrogen ions away from methanogens. Current literature has identified new CH4 mitigation options. These include the addition of probiotics, acetogens, bacteriocins, archaeal viruses, organic acids, plant extracts (e.g., essential oils) to the diet, as well as immunization, and genetic selection of cows. These new strategies are promising, but more research is needed to validate these approaches and to assess in vivo their effectiveness in reducing CH4 production by dairy cows. It is also important to evaluate CH4 mitigation strategies in terms of the total greenhouse gas budget and to consider the cost associated with the various strategies. More basic understanding of the natural differences in digestion efficiencies among animals as well as a better knowledge of methanogens and their interaction with other organisms in the rumen would enable us to exploit the potential of some of the new CH4 mitigation strategies for dairy cattle production. Key words: Enteric methane, dairy cattle, mitigation