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Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle

Management of metabolic hydrogen ([H]) in the rumen has been identified as an important consideration when reducing ruminant CH(4) emissions. However, little is known about hydrogen flux and microbial rumen population responses to CH(4) inhibition when animals are fed with slowly degradable diets. T...

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Autores principales: Martinez-Fernandez, Gonzalo, Denman, Stuart E., Yang, Chunlei, Cheung, Jane, Mitsumori, Makoto, McSweeney, Christopher S.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4949212/
https://www.ncbi.nlm.nih.gov/pubmed/27486452
http://dx.doi.org/10.3389/fmicb.2016.01122
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author Martinez-Fernandez, Gonzalo
Denman, Stuart E.
Yang, Chunlei
Cheung, Jane
Mitsumori, Makoto
McSweeney, Christopher S.
author_facet Martinez-Fernandez, Gonzalo
Denman, Stuart E.
Yang, Chunlei
Cheung, Jane
Mitsumori, Makoto
McSweeney, Christopher S.
author_sort Martinez-Fernandez, Gonzalo
collection PubMed
description Management of metabolic hydrogen ([H]) in the rumen has been identified as an important consideration when reducing ruminant CH(4) emissions. However, little is known about hydrogen flux and microbial rumen population responses to CH(4) inhibition when animals are fed with slowly degradable diets. The effects of the anti-methanogenic compound, chloroform, on rumen fermentation, microbial ecology, and H(2)/CH(4) production were investigated in vivo. Eight rumen fistulated Brahman steers were fed a roughage hay diet (Rhode grass hay) or roughage hay:concentrate diet (60:40) with increasing levels (low, mid, and high) of chloroform in a cyclodextrin matrix. The increasing levels of chloroform resulted in an increase in H(2) expelled as CH(4) production decreased with no effect on dry matter intakes. The amount of expelled H(2) per mole of decreased methane, was lower for the hay diet suggesting a more efficient redirection of hydrogen into other microbial products compared with hay:concentrate diet. A shift in rumen fermentation toward propionate and branched-chain fatty acids was observed for both diets. Animals fed with the hay:concentrate diet had both higher formate concentration and H(2) expelled than those fed only roughage hay. Metabolomic analyses revealed an increase in the concentration of amino acids, organic, and nucleic acids in the fluid phase for both diets when methanogenesis was inhibited. These changes in the rumen metabolism were accompanied by a shift in the microbiota with an increase in Bacteroidetes:Firmicutes ratio and a decrease in Archaea and Synergistetes for both diets. Within the Bacteroidetes family, some OTUs assigned to Prevotella were promoted under chloroform treatment. These bacteria may be partly responsible for the increase in amino acids and propionate in the rumen. No significant changes were observed for abundance of fibrolytic bacteria, protozoa, and fungi, which suggests that fiber degradation was not impaired. The observed 30% decrease in methanogenesis did not adversely affect rumen metabolism and the rumen microbiota was able to adapt and redirect [H] into other microbial end-products for both diets. However, it is also required dietary supplements or microbial treatments to capture the additional H(2) expelled by the animal to further improve rumen digestive efficiency.
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spelling pubmed-49492122016-08-02 Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle Martinez-Fernandez, Gonzalo Denman, Stuart E. Yang, Chunlei Cheung, Jane Mitsumori, Makoto McSweeney, Christopher S. Front Microbiol Microbiology Management of metabolic hydrogen ([H]) in the rumen has been identified as an important consideration when reducing ruminant CH(4) emissions. However, little is known about hydrogen flux and microbial rumen population responses to CH(4) inhibition when animals are fed with slowly degradable diets. The effects of the anti-methanogenic compound, chloroform, on rumen fermentation, microbial ecology, and H(2)/CH(4) production were investigated in vivo. Eight rumen fistulated Brahman steers were fed a roughage hay diet (Rhode grass hay) or roughage hay:concentrate diet (60:40) with increasing levels (low, mid, and high) of chloroform in a cyclodextrin matrix. The increasing levels of chloroform resulted in an increase in H(2) expelled as CH(4) production decreased with no effect on dry matter intakes. The amount of expelled H(2) per mole of decreased methane, was lower for the hay diet suggesting a more efficient redirection of hydrogen into other microbial products compared with hay:concentrate diet. A shift in rumen fermentation toward propionate and branched-chain fatty acids was observed for both diets. Animals fed with the hay:concentrate diet had both higher formate concentration and H(2) expelled than those fed only roughage hay. Metabolomic analyses revealed an increase in the concentration of amino acids, organic, and nucleic acids in the fluid phase for both diets when methanogenesis was inhibited. These changes in the rumen metabolism were accompanied by a shift in the microbiota with an increase in Bacteroidetes:Firmicutes ratio and a decrease in Archaea and Synergistetes for both diets. Within the Bacteroidetes family, some OTUs assigned to Prevotella were promoted under chloroform treatment. These bacteria may be partly responsible for the increase in amino acids and propionate in the rumen. No significant changes were observed for abundance of fibrolytic bacteria, protozoa, and fungi, which suggests that fiber degradation was not impaired. The observed 30% decrease in methanogenesis did not adversely affect rumen metabolism and the rumen microbiota was able to adapt and redirect [H] into other microbial end-products for both diets. However, it is also required dietary supplements or microbial treatments to capture the additional H(2) expelled by the animal to further improve rumen digestive efficiency. Frontiers Media S.A. 2016-07-19 /pmc/articles/PMC4949212/ /pubmed/27486452 http://dx.doi.org/10.3389/fmicb.2016.01122 Text en Copyright © 2016 Martinez-Fernandez, Denman, Yang, Cheung, Mitsumori and McSweeney. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Microbiology
Martinez-Fernandez, Gonzalo
Denman, Stuart E.
Yang, Chunlei
Cheung, Jane
Mitsumori, Makoto
McSweeney, Christopher S.
Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle
title Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle
title_full Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle
title_fullStr Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle
title_full_unstemmed Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle
title_short Methane Inhibition Alters the Microbial Community, Hydrogen Flow, and Fermentation Response in the Rumen of Cattle
title_sort methane inhibition alters the microbial community, hydrogen flow, and fermentation response in the rumen of cattle
topic Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4949212/
https://www.ncbi.nlm.nih.gov/pubmed/27486452
http://dx.doi.org/10.3389/fmicb.2016.01122
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