Rumen microbiome response to methane inhibition
Ibrahim Ahmad A * , Richard P. Rawnsley A , John P. Bowman A and Apeh A. Omede AA
Ibrahim Ahmad is a veterinarian and a PhD candidate at the Tasmanian Institute of Agriculture (TIA), University of Tasmania. He has several years of experience in general veterinary practice, meat inspection and research. His research interests include mitigation of enteric methane emissions from grass-fed dairy and beef production systems, rumen microbiology, animal nutrition and livestock systems modelling. |
Assoc. Prof. Richard Rawnsley is the academic lead for the Livestock Production Centre within the TIA. His research focuses on developing practical, science-based solutions to enhance both animal performance and the sustainability of pasture-based livestock systems. |
Prof. John P. Bowman is a microbiologist based in Launceston, Tas., where he is the professor of microbiology at the University of Tasmania. He is the leader of the Centre for Food Safety and Innovation within the Tasmanian Institute of Agriculture. His interests are broad and cover many aspects of food and agricultural systems, microbial ecology and systematics. He is a Fellow of the Australian Society of Microbiology. He completed his PhD (and DSc) at The University of Queensland and has been a researcher and lecturer at the University of Tasmania since the mid-1990s. |
Dr Apeh A. Omede is a lecturer and researcher in animal production at the TIA, University of Tasmania. He is interested in researching the interphase between nutritional strategies for sustainable animal production, the environment and gut microbiome in farm animals. He was a Marie Curie COFUND postdoc at Teagasc Ireland before joining the University of Tasmania. |
Abstract
Rumen microbiota ferment feed into various by-products, some of which are used by methanogens to produce enteric methane (CH4), a potent greenhouse gas (GHG) that significantly contributes to climate change. The use of CH4 inhibitors, such as Asparagopsis spp. and 3-nitrooxypropanol (3-NOP), in ruminant feed has been shown to be effective in reducing methanogenesis. However, inhibition of enteric CH4 leads to inconsistent productivity gains, partly due to the shift in significant fermentative microbes away from acetogenesis and the inability to convert increased ruminal dihydrogen (H2) spared from methanogenesis into absorbable nutrients beneficial to the host animals. Mitigation of CH4 synthesis paired with redirection of ruminal H2 to preserve normal rumen functions could be one of the most promising strategies to improve ruminant productivity while feeding CH4 inhibitors. This review highlights the growing knowledge of the rumen microbiome response to CH4 inhibition and explores the potential benefits of co-supplementing CH4 inhibitors with electron acceptors to optimise rumen function as a future direction to supporting the voluntary on-farm adoption of anti-methanogenic feed additives (AMFAs) across livestock systems.
Keywords: 3-NOP, Asparagopsis, feed additive, greenhouse gas, methane emission, methane inhibition, methanogenesis, rumen fermentation, rumen microbiome, ruminants.
Ibrahim Ahmad is a veterinarian and a PhD candidate at the Tasmanian Institute of Agriculture (TIA), University of Tasmania. He has several years of experience in general veterinary practice, meat inspection and research. His research interests include mitigation of enteric methane emissions from grass-fed dairy and beef production systems, rumen microbiology, animal nutrition and livestock systems modelling. |
Assoc. Prof. Richard Rawnsley is the academic lead for the Livestock Production Centre within the TIA. His research focuses on developing practical, science-based solutions to enhance both animal performance and the sustainability of pasture-based livestock systems. |
Prof. John P. Bowman is a microbiologist based in Launceston, Tas., where he is the professor of microbiology at the University of Tasmania. He is the leader of the Centre for Food Safety and Innovation within the Tasmanian Institute of Agriculture. His interests are broad and cover many aspects of food and agricultural systems, microbial ecology and systematics. He is a Fellow of the Australian Society of Microbiology. He completed his PhD (and DSc) at The University of Queensland and has been a researcher and lecturer at the University of Tasmania since the mid-1990s. |
Dr Apeh A. Omede is a lecturer and researcher in animal production at the TIA, University of Tasmania. He is interested in researching the interphase between nutritional strategies for sustainable animal production, the environment and gut microbiome in farm animals. He was a Marie Curie COFUND postdoc at Teagasc Ireland before joining the University of Tasmania. |
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