Molecular hydrogen produced by elemental magnesium inhibits rumen fermentation and enhances methanogenesis in dairy cows
Year: 2019
Type: article
Abstract: Hydrogen is a key metabolite that connects microbial fermentation and methanogenesis in the rumen. This study was to investigate the effects of elevated H 2 produced by elemental Mg on rumen fermentation and methanogenesis in dairy cows. Four nonlactating Chinese Holstein dairy cows were employed for this experiment in a replicated crossover design. The 2 dietary treatments included a basal diet supplemented with Mg(OH) 2 (14.5 g/kg of feed dry matter) or elemental Mg (6.00 g/kg of feed dry matter). When compared with Mg(OH) 2 treatment, cows fed diet with elemental Mg had similar rumen Mg 2+ concentration, but higher rumen dissolved H 2 and methane concentrations at 2.5 h after morning feeding. Also, elemental Mg supplementation decreased feed digestibility, rumen volatile fatty acid concentration, and relative abundance of group Ruminococcaceae_UCG-014 , genus Bifidobacterium , and group Mollicutes_RF9 , increased acetate to propionate ratio, succinate concentration, and abundance of family Christensenellaceae . Elemental Mg supplementation increased enteric CH 4 emission, altered methanogen community with increased abundance of order Methanomassiliicoccales , 16S ribosomal RNA gene copies of methanogens, and order Methanobacteriales . In summary, the pulse of elevated dissolved H 2 after feeding produced by elemental Mg inhibited rumen fermentation and feed digestibility by decreasing the abundance of carbohydrate-degrading bacteria, promoted H 2 incorporation into succinate by increasing family Christensenellaceae and genus Bacteroidales_BS11 , and increased H 2 utilization for methanogenesis by favoring growth of methanogens.
Source: Journal of Dairy Science
Authors: Zhi Yuan Ma, Xiu Min Zhang, Min Wang, Rong Wang, Zai Yang Jiang, Zhi Liang Tan, Feng Xian Gao, Arowolo Muhammed
Language: English
Subfield: Animal Science and Zoology
Domain: Life Sciences
SDG: Zero hunger
Open Access status: bronze
OpenAlex ID: W2936341216