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O'Donnell C, Thorn C, Roskam E, Friel R, Kirwan SF, Waters SM, O'Flaherty V. Novel oxidising feed additives reduce in vitro methane emissions using the rumen simulation technique. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171808. [PMID: 38508273 DOI: 10.1016/j.scitotenv.2024.171808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 03/14/2024] [Accepted: 03/16/2024] [Indexed: 03/22/2024]
Abstract
Enteric methane (CH4) produced by ruminant livestock is a potent greenhouse gas and represents significant energy loss for the animal. The novel application of oxidising compounds as antimethanogenic agents with future potential to be included in ruminant feeds, was assessed across two separate experiments in this study. Low concentrations of oxidising agents, namely urea hydrogen peroxide (UHP) with and without potassium iodide (KI), and magnesium peroxide (MgO2), were investigated for their effects on CH4 production, total gas production (TGP), volatile fatty acid (VFA) profiles, and nutrient disappearance in vitro using the rumen simulation technique. In both experiments, the in vitro diet consisted of 50:50 grass silage:concentrate on a dry matter basis. Treatment concentrations were based on the amount of oxygen delivered and expressed in terms of fold concentration. In Experiment 1, four treatments were tested (Control, 1× UHP + KI, 1× UHP, and 0.5× UHP + KI), and six treatments were assessed in Experiment 2 (Control, 0.5× UHP + KI, 0.5× UHP, 0.25× UHP + KI, 0.25× UHP, and 0.12× MgO2). All treatments in this study had a reducing effect on CH4 parameters. A dose-dependent reduction of TGP and CH4 parameters was observed, where treatments delivering higher levels of oxygen resulted in greater CH4 suppression. 1× UHP + KI reduced TGP by 28 % (p = 0.611), CH4% by 64 % (p = 0.075) and CH4 mmol/g digestible organic matter by 71 % (p = 0.037). 0.12× MgO2 reduced CH4 volume by 25 % (p > 0.05) without affecting any other parameters. Acetate-to-propionate ratios were reduced by treatments in both experiments (p < 0.01). Molar proportions of acetate and butyrate were reduced, while propionate and valerate were increased in UHP treatments. High concentrations of UHP affected the degradation of neutral detergent fibre in the forage substrate. Future in vitro work should investigate alternative slow-release oxygen sources aimed at prolonging CH4 suppression.
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Affiliation(s)
- Caroline O'Donnell
- Microbial Ecology Laboratory, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland.
| | - Camilla Thorn
- GlasPort Bio Ltd, Business Innovation Centre, University of Galway, Galway, Ireland
| | - Emily Roskam
- Microbial Ecology Laboratory, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland; Teagasc Animal and Bioscience Research Department, Teagasc Grange, Meath, Ireland
| | - Ruairi Friel
- GlasPort Bio Ltd, Business Innovation Centre, University of Galway, Galway, Ireland
| | - Stuart F Kirwan
- Teagasc Animal and Bioscience Research Department, Teagasc Grange, Meath, Ireland
| | - Sinéad M Waters
- Teagasc Animal and Bioscience Research Department, Teagasc Grange, Meath, Ireland; School of Biological and Chemical Sciences, University of Galway, Galway, Ireland
| | - Vincent O'Flaherty
- Microbial Ecology Laboratory, School of Biological and Chemical Sciences, University of Galway, Galway, Ireland; GlasPort Bio Ltd, Business Innovation Centre, University of Galway, Galway, Ireland.
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Ungerfeld EM, Pitta D. Review: Biological consequences of the inhibition of rumen methanogenesis. Animal 2024:101170. [PMID: 38772773 DOI: 10.1016/j.animal.2024.101170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 05/23/2024] Open
Abstract
Decreasing enteric CH4 emissions from ruminants is important for containing global warming to 1.5 °C and avoid the worst consequences of climate change. However, the objective of mitigating enteric CH4 emissions is difficult to reconcile with the forecasted increase in production of ruminant meat and milk, unless CH4 production per animal and per kilogram of animal product are decreased substantially. Chemical compound 3-nitrooxypropanol and bromoform-containing red algae Asparagopsis are currently the most potent inhibitors of rumen methanogenesis, but their average efficacy would have to be increased to mitigate enteric CH4 emissions to contain global warming to 1.5 °C, if the demand for ruminant products increases as predicted. We propose that it may be possible to enhance the efficacy of inhibitors of methanogenesis through understanding the mechanisms that cause variation in their efficacy across studies. We also propose that a more thorough understanding of the effects of inhibiting methanogenesis on rumen and postabsorptive metabolism may help improve feed efficiency and cost-effectiveness as co-benefits of the methanogenesis inhibition intervention. For enhancing efficacy, we examine herein how different inhibitors of methanogenesis affect the composition of the rumen microbial community and discuss some mechanisms that may explain dissimilar sensitivities among methanogens to different types of inhibitors. For improving feed efficiency and cost-effectiveness, we discuss the consequences of inhibiting methanogenesis on rumen fermentation, and how changes in rumen fermentation can in turn affect postabsorptive metabolism and animal performance. The objectives of this review are to identify knowledge gaps of the consequences of inhibiting methanogenesis on rumen microbiology and rumen and postabsorptive metabolism, propose research to address those knowledge gaps and discuss the implications that this research can have for the efficacy and adoption of inhibitors of methanogenesis. Depending on its outcomes, research on the microbiological, biochemical, and metabolic consequences of the inhibition of rumen methanogenesis could help the adoption of feed additives inhibitors of methanogenesis to mitigate enteric CH4 emissions from ruminants to ameliorate climate change.
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Affiliation(s)
- E M Ungerfeld
- Centro Regional de Investigación Carillanca, Instituto de Investigaciones Agropecuarias INIA, Camino Cajón a Vilcún km 10, 4880000 Vilcún, La Araucanía, Chile.
| | - D Pitta
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, New Bolton Center, 19348 Kenneth Square, PA, United States
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Li J, Zhao S, Meng Z, Gao Y, Miao J, Mao S, Jin W. Effects of Fumarate and Nitroglycerin on In Vitro Rumen Fermentation, Methane and Hydrogen Production, and on Microbiota. BIOLOGY 2023; 12:1011. [PMID: 37508440 PMCID: PMC10376899 DOI: 10.3390/biology12071011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/08/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023]
Abstract
This study aimed to investigate the effects of fumarate and nitroglycerin on rumen fermentation, methane and hydrogen production, and microbiota. In vitro rumen fermentation was used in this study with four treatment groups: control (CON), fumarate (FA), nitroglycerin (NG) and fumarate plus nitroglycerin (FN). Real-time PCR and 16S rRNA gene sequencing were used to analyze microbiota. The results showed that nitroglycerin completely inhibited methane production and that this resulted in hydrogen accumulation. Fumarate decreased the hydrogen accumulation and improved the rumen fermentation parameters. Fumarate increased the concentration of propionate and microbial crude protein, and decreased the ratio of acetate to propionate in FN. Fumarate, nitroglycerin and their combination did not affect the abundance of bacteria, protozoa and anaerobic fungi, but altered archaea. The PCoA showed that the bacterial (Anosim, R = 0.747, p = 0.001) and archaeal communities (Anosim, R = 0.410, p = 0.005) were different among the four treatments. Compared with CON, fumarate restored Bacteroidetes, Firmicutes, Spirochaetae, Actinobacteria, Unclassified Ruminococcaceae, Streptococcus, Treponema and Bifidobacterium in relative abundance in FN, but did not affect Succinivibrio, Ruminobacter and archaeal taxa. The results indicated that fumarate alleviated the depressed rumen fermentation caused by the inhibition of methanogenesis by nitroglycerin. This may potentially provide an alternative way to use these chemicals to mitigate methane emission in ruminants.
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Affiliation(s)
- Jichao Li
- Ruminant Nutrition and Feed Engineering Technology Research Center, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Gastrointestinal Microbiology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Shengwei Zhao
- Ruminant Nutrition and Feed Engineering Technology Research Center, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Gastrointestinal Microbiology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhenxiang Meng
- Ruminant Nutrition and Feed Engineering Technology Research Center, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Gastrointestinal Microbiology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Yunlong Gao
- Ruminant Nutrition and Feed Engineering Technology Research Center, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Gastrointestinal Microbiology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Jing Miao
- Ruminant Nutrition and Feed Engineering Technology Research Center, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Shengyong Mao
- Ruminant Nutrition and Feed Engineering Technology Research Center, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Gastrointestinal Microbiology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
| | - Wei Jin
- Ruminant Nutrition and Feed Engineering Technology Research Center, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
- Laboratory of Gastrointestinal Microbiology, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
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Liu Z, Wang K, Nan X, Yang L, Wang Y, Zhang F, Cai M, Zhao Y, Xiong B. Effects of combined addition of 3-nitrooxypropanol and vitamin B12 on methane and propionate production in dairy cows by in vitro-simulated fermentation. J Dairy Sci 2022; 106:219-232. [DOI: 10.3168/jds.2022-22207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 08/13/2022] [Indexed: 11/09/2022]
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Synergistic effects of 3-nitrooxypropanol with fumarate in the regulation of propionate formation and methanogenesis in dairy cows in vitro. Appl Environ Microbiol 2022; 88:e0190821. [PMID: 35080908 DOI: 10.1128/aem.01908-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
3-nitrooxypropanol (3-NOP) is effective in reducing ruminal methane emission in ruminants. But it also causes a drastic increase in hydrogen accumulation, resulting in a feed energy waste. Fumarate is a key precursor for propionate formation and plays an important role in rumen hydrogen metabolism. Therefore, this study examined the effects of 3-NOP combined with fumarate on volatile fatty acids, methanogenesis and microbial community structures in dairy cows in vitro . The in vitro culture experiment was performed using a 2 × 2 factorial design: two 3-NOP levels (0 or 2 mg/g DM) and two fumarate levels (0 or 100 mg/g DM), including 3 runs × 4 treatments × 4 replicates and 4 blanks only containing inoculum. Rumen fluid was collected from three lactating Holstein cows with permanent ruminal fistulas. The combination of 3-NOP and fumarate reduced methane emission by 11.48% without affecting dry matter degradebility. Propionate concentration increased and acetate/propionate ratio decreased significantly. In terms of bacteria, the combination of 3-NOP and fumarate reduced the abundance of Ruminococcus and Lachnospiraceae_NK3A20_group and increased the abundance of Prevotella and Succiniclasticum. For archaea, the combination of 3-NOP and fumarate significantly increased the abundance of Methanobrevibacter_sp._AbM4, while the abundance of OTU581 (belongs to strain uncultured_rumen_methanogen_g__Methanobrevibacter) was significantly decreased. These results indecated that the combination of 3-NOP with fumarate could alleviate the accumulation of hydrogen and enhance the inhibition of methanogenesis compared with 3-NOP only in dairy cows. IMPORTANCE The global problem of climate change and the greenhouse effect has become increasingly severe, and the abatement of greenhouse gases has received great attention from the international community. Methane produced by ruminants during digestion not only aggravates the greenhouse effect, but also causes a waste of feed energy. As a methane inhibitor, 3-nitrooxypropanol can effectively reduce methane emission from ruminants. However, when it inhibits methane emission, the emission of hydrogen increases sharply, resulting in the waste of feed resources. Fumarate is a propionic acid precursor, which can promote the metabolism of hydrogen to propionic acid in animals. Therefore, we studied the effects of the combined addition of 3-nitrooxypropanol and fumarate on methanogenesis, rumen fermentation and rumen flora. It is of great significance to inhibit methane emission from ruminants and slow down the greenhouse effect.
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Yu G, Beauchemin KA, Dong R. A Review of 3-Nitrooxypropanol for Enteric Methane Mitigation from Ruminant Livestock. Animals (Basel) 2021; 11:3540. [PMID: 34944313 PMCID: PMC8697901 DOI: 10.3390/ani11123540] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/08/2021] [Accepted: 12/08/2021] [Indexed: 11/16/2022] Open
Abstract
Methane (CH4) from enteric fermentation accounts for 3 to 5% of global anthropogenic greenhouse gas emissions, which contribute to climate change. Cost-effective strategies are needed to reduce feed energy losses as enteric CH4 while improving ruminant production efficiency. Mitigation strategies need to be environmentally friendly, easily adopted by producers and accepted by consumers. However, few sustainable CH4 mitigation approaches are available. Recent studies show that the chemically synthesized CH4 inhibitor 3-nitrooxypropanol is one of the most effective approaches for enteric CH4 abatement. 3-nitrooxypropanol specifically targets the methyl-coenzyme M reductase and inhibits the final catalytic step in methanogenesis in rumen archaea. Providing 3-nitrooxypropanol to dairy and beef cattle in research studies has consistently decreased enteric CH4 production by 30% on average, with reductions as high as 82% in some cases. Efficacy is positively related to 3-NOP dose and negatively affected by neutral detergent fiber concentration of the diet, with greater responses in dairy compared with beef cattle when compared at the same dose. This review collates the current literature on 3-nitrooxypropanol and examines the overall findings of meta-analyses and individual studies to provide a synthesis of science-based information on the use of 3-nitrooxypropanol for CH4 abatement. The intent is to help guide commercial adoption at the farm level in the future. There is a significant body of peer-reviewed scientific literature to indicate that 3-nitrooxypropanol is effective and safe when incorporated into total mixed rations, but further research is required to fully understand the long-term effects and the interactions with other CH4 mitigating compounds.
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Affiliation(s)
- Guanghui Yu
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao 266109, China;
| | - Karen A. Beauchemin
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, 5403 1st Avenue South, Lethbridge, AB T1J 4B1, Canada;
| | - Ruilan Dong
- College of Animal Science and Technology, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao 266109, China;
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Li Z, Lei X, Chen X, Yin Q, Shen J, Yao J. Long-term and combined effects of N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide and fumaric acid on methane production, rumen fermentation, and lactation performance in dairy goats. J Anim Sci Biotechnol 2021; 12:125. [PMID: 34865657 PMCID: PMC8647438 DOI: 10.1186/s40104-021-00645-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 10/26/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In recent years, nitrooxy compounds have been identified as promising inhibitors of methanogenesis in ruminants. However, when animals receive a nitrooxy compound, a high portion of the spared hydrogen is eructated as gas, which partly offsets the energy savings of CH4 mitigation. The objective of the present study was to evaluate the long-term and combined effects of supplementation with N-[2-(nitrooxy)ethyl]-3-pyridinecarboxamide (NPD), a methanogenesis inhibitor, and fumaric acid (FUM), a hydrogen sink, on enteric CH4 production, rumen fermentation, bacterial populations, apparent nutrient digestibility, and lactation performance of dairy goats. RESULTS Twenty-four primiparous dairy goats were used in a randomized complete block design with a 2 × 2 factorial arrangement of treatments: supplementation without or with FUM (32 g/d) or NPD (0.5 g/d). All samples were collected every 3 weeks during a 12-week feeding experiment. Both FUM and NPD supplementation persistently inhibited CH4 yield (L/kg DMI, by 18.8% and 18.1%, respectively) without negative influence on DMI or apparent nutrient digestibility. When supplemented in combination, no additive CH4 suppression was observed. FUM showed greater responses in increasing the molar proportion of propionate when supplemented with NPD than supplemented alone (by 10.2% vs. 4.4%). The rumen microbiota structure in the animals receiving FUM was different from that of the other animals, particularly changed the structure of phylum Firmicutes. Daily milk production and serum total antioxidant capacity were improved by NPD, but the contents of milk fat and protein were decreased, probably due to the bioactivity of absorbed NPD on body metabolism. CONCLUSIONS Supplementing NPD and FUM in combination is a promising way to persistently inhibit CH4 emissions with a higher rumen propionate proportion. However, the side effects of this nitrooxy compound on animals and its residues in animal products need further evaluation before it can be used as an animal feed additive.
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Affiliation(s)
- Zongjun Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xinjian Lei
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Xiaoxu Chen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Qingyan Yin
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Jing Shen
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China
| | - Junhu Yao
- College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, Shaanxi, China.
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Pfau F, Hünerberg M, Südekum KH, Breves G, Clauss M, Hummel J. Effects of Dilution Rate on Fermentation Characteristics of Feeds With Different Carbohydrate Composition Incubated in the Rumen Simulation Technique (RUSITEC). FRONTIERS IN ANIMAL SCIENCE 2021. [DOI: 10.3389/fanim.2021.715142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
This study investigated the impact of carbohydrate source and fluid passage rate (dilution rate) on ruminal fermentation characteristics and microbial crude protein (MCP) formation. Three commonly used feeds (barley grain [BG], beet pulp [BP], and soybean hulls [SBH]), which differ considerably in their carbohydrate composition, were incubated together with a mixture of grass hay and rapeseed meal in two identical Rusitec apparatuses (each 6 vessels). Differences in fluid passage rate were simulated by infusing artificial saliva at two different rates (1.5% [low] and 3.0% [high] of fermenter volume per h). This resulted in six treatments (tested in 3 runs): BGhigh, BGlow, BPhigh, BPlow, SBHhigh and SBHlow. The system was adapted for 7 d, followed by 4 d of sampling. Production of MCP (mg/g degraded organic matter [dOM]; estimated by 15N analysis) was greater with high dilution rate (DL; p < 0.001) and was higher for SBH compared to both BG and BP (p < 0.001). High DL reduced OM degradability (OMD) compared to low DL (p < 0.001), whereas incubation of BG resulted in higher OMD compared to SBH (p < 0.002). Acetate:propionate ratio decreased in response to high DL (p < 0.001). Total gas and methane production (both /d and /g dOM) were lower with high DL (p < 0.001). In our study increasing liquid passage rate showed the potential to increase MCP and decrease methane production simultaneously. Results encourage further studies investigating these effects on the rumen microbial population.
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Schilde M, von Soosten D, Hüther L, Kersten S, Meyer U, Zeyner A, Dänicke S. Dose-Response Effects of 3-Nitrooxypropanol Combined with Low- and High-Concentrate Feed Proportions in the Dairy Cow Ration on Fermentation Parameters in a Rumen Simulation Technique. Animals (Basel) 2021; 11:1784. [PMID: 34203718 PMCID: PMC8232248 DOI: 10.3390/ani11061784] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/09/2021] [Accepted: 06/10/2021] [Indexed: 11/17/2022] Open
Abstract
Methane (CH4) from ruminal feed degradation is a major pollutant from ruminant livestock, which calls for mitigation strategies. The purpose of the present 4 × 2 factorial arrangement was to investigate the dose-response relationships between four doses of the CH4 inhibitor 3-nitrooxypropanol (3-NOP) and potential synergistic effects with low (LC) or high (HC) concentrate feed proportions (CFP) on CH4 reduction as both mitigation approaches differ in their mode of action (direct 3-NOP vs. indirect CFP effects). Diet substrates and 3-NOP were incubated in a rumen simulation technique to measure the concentration and production of volatile fatty acids (VFA), fermentation gases as well as substrate disappearance. Negative side effects on fermentation regarding total VFA and gas production as well as nutrient degradability were observed for neither CFP nor 3-NOP. CH4 production decreased from 10% up to 97% in a dose-dependent manner with increasing 3-NOP inclusion rate (dose: p < 0.001) but irrespective of CFP (CFP × dose: p = 0.094). Hydrogen gas accumulated correspondingly with increased 3-NOP dose (dose: p < 0.001). In vitro pH (p = 0.019) and redox potential (p = 0.066) varied by CFP, whereas the latter fluctuated with 3-NOP dose (p = 0.01). Acetate and iso-butyrate (mol %) decreased with 3-NOP dose, whereas iso-valerate increased (dose: p < 0.001). Propionate and valerate varied inconsistently due to 3-NOP supplementation. The feed additive 3-NOP was proven to be a dose-dependent yet effective CH4 inhibitor under conditions in vitro. The observed lack of additivity of increased CFP on the CH4 inhibition potential of 3-NOP needs to be verified in future research testing further diet types both in vitro and in vivo.
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Affiliation(s)
- Matthias Schilde
- Institute of Animal Nutrition, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany; (D.v.S.); (L.H.); (S.K.); (U.M.); (S.D.)
| | - Dirk von Soosten
- Institute of Animal Nutrition, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany; (D.v.S.); (L.H.); (S.K.); (U.M.); (S.D.)
| | - Liane Hüther
- Institute of Animal Nutrition, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany; (D.v.S.); (L.H.); (S.K.); (U.M.); (S.D.)
| | - Susanne Kersten
- Institute of Animal Nutrition, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany; (D.v.S.); (L.H.); (S.K.); (U.M.); (S.D.)
| | - Ulrich Meyer
- Institute of Animal Nutrition, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany; (D.v.S.); (L.H.); (S.K.); (U.M.); (S.D.)
| | - Annette Zeyner
- Institute of Agricultural and Nutritional Sciences, Group Animal Nutrition, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany;
| | - Sven Dänicke
- Institute of Animal Nutrition, Friedrich-Loeffler-Institut (FLI), Federal Research Institute for Animal Health, 38116 Braunschweig, Germany; (D.v.S.); (L.H.); (S.K.); (U.M.); (S.D.)
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Early life dietary intervention in dairy calves results in a long-term reduction in methane emissions. Sci Rep 2021; 11:3003. [PMID: 33542279 PMCID: PMC7862406 DOI: 10.1038/s41598-021-82084-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 01/15/2021] [Indexed: 02/06/2023] Open
Abstract
Recent evidence suggests that changes in microbial colonization of the rumen prior to weaning may imprint the rumen microbiome and impact phenotypes later in life. We investigated how dietary manipulation from birth influences growth, methane production, and gastrointestinal microbial ecology. At birth, 18 female Holstein and Montbéliarde calves were randomly assigned to either treatment or control (CONT). Treatment was 3-nitrooxypropanol (3-NOP), an investigational anti-methanogenic compound that was administered daily from birth until three weeks post-weaning (week 14). Samples of rumen fluid and faecal content were collected at weeks 1, 4, 11, 14, 23, and 60 of life. Calves were tested for methane emissions using the GreenFeed system during the post-weaning period (week 11–23 and week 56–60 of life). Calf physiological parameters (BW, ADG and individual VFA) were similar across groups throughout the trial. Treated calves showed a persistent reduction in methane emissions (g CH4/d) throughout the post-weaning period up to at least 1 year of life, despite treatment ceasing three weeks post-weaning. Similarly, despite variability in the abundance of individual taxa across weeks, the rumen bacterial, archaeal and fungal structure differed between CONT and 3-NOP calves across all weeks, as visualised using sparse-PLS-DA. Similar separation was also observed in the faecal bacterial community. Interestingly, despite modest modifications to the abundance of rumen microbes, the reductive effect of 3-NOP on methane production persisted following cessation of the treatment period, perhaps indicating a differentiation of the ruminal microbial ecosystem or a host response triggered by the treatment in the early development phase.
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Kim SH, Lee C, Pechtl HA, Hettick JM, Campler MR, Pairis-Garcia MD, Beauchemin KA, Celi P, Duval SM. Effects of 3-nitrooxypropanol on enteric methane production, rumen fermentation, and feeding behavior in beef cattle fed a high-forage or high-grain diet1. J Anim Sci 2019; 97:2687-2699. [PMID: 31115441 DOI: 10.1093/jas/skz140] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 04/18/2019] [Indexed: 11/13/2022] Open
Abstract
The objective of the study was to determine whether feeding a diet supplemented with 3-nitrooxypropanol (3-NOP) affects feeding behavior altering intake and rumen fermentation. Two experiments were conducted with 9 rumen-cannulated beef steers in a replicated 3 × 3 Latin square design where animals received a high-forage or high-grain diet. Treatments were 1) a basal diet (CON), the CON diet supplemented with 3-NOP (dNOP; 100 mg/kg in dietary DM or 1 g/d), or the CON diet with 3-NOP (1 g/d) infused into the rumen (infNOP). Each experimental period consisted of 14-d diet adaptation and 7-d sample collection. A 7-d washout period was provided between experiment periods. All data were analyzed as a Latin square design using Mixed Procedure of SAS. In Exp. 1 (high-forage diet), methane yield (measured by the Greenfeed system) was lowered by 18% (18.6 vs. 22.7 g/kg DMI; P < 0.01) by dNOP compared with CON. Rumen fermentation was altered similarly by both NOP treatments compared with CON where dNOP and infNOP increased (P < 0.01) rumen pH at 3 h and decreased (P < 0.01) proportion of acetate in total VFA. However, DMI, feed consumption rate (0 to 3, 3 to 6, 6 to 12, and 12 to 24 h after feeding), particle size distribution of orts, and feeding behavior (videotaped for individual animals over 48 h) were not affected by dNOP and infNOP compared with CON. In Exp. 2 (high-grain diet), methane production was not affected by dNOP or infNOP compared with CON. Dry matter intake, feed consumption rate, particle size distribution of orts, and feeding behavior were not altered by dNOP and infNOP compared with CON. However, both dNOP and infNOP affected rumen fermentation where total VFA decreased (P = 0.04) and acetate proportion in total VFA tended to decrease (P = 0.07) compared with CON. In conclusion, dietary supplementation of 3-NOP did not affect feeding behavior of beef steers fed a high-forage or high-grain diet. However, rumen fermentation was similarly changed when 3-NOP was provided in the diet or directly infused in the rumen. Thus, observed changes in rumen fermentation with 3-NOP were not due to changes in feeding behavior indicating no effects on the organoleptic property of the diets. In addition, according to small or no changes in DMI in both experiments and relatively small changes in rumen fermentation in Exp. 2, a greater dosage level of 3-NOP than 100 mg/kg (dietary DM) may need further examination of its effects on feeding behavior of beef cattle.
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Affiliation(s)
- Seon-Ho Kim
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, the Ohio State University, Wooster, OH
| | - Chanhee Lee
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, the Ohio State University, Wooster, OH
| | - Heather A Pechtl
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, the Ohio State University, Wooster, OH
| | - Jade M Hettick
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, the Ohio State University, Wooster, OH
| | - Magnus R Campler
- Department of Animal Sciences, the Ohio State University, Columbus, OH
| | | | - Karen A Beauchemin
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Alberta, Canada
| | - Pietro Celi
- DSM Nutritional Products France, Research Center for Animal Nutrition, 68305 Saint Louis Cedex, France
| | - Stephane M Duval
- DSM Nutritional Products France, Research Center for Animal Nutrition, 68305 Saint Louis Cedex, France
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Wei C, Guyader J, Collazos L, Beauchemin KA, Zhao GY. Effects of gallic acid on in vitro rumen fermentation and methane production using rumen simulation (Rusitec) and batch-culture techniques. ANIMAL PRODUCTION SCIENCE 2019. [DOI: 10.1071/an17365] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Two experiments were conducted to investigate the effects of adding gallic acid (GA) to ruminant diets on long- and short-term in vitro rumen fermentation and methane (CH4) production, and to test possible interactions between GA and ethanol on fermentation. The first experiment was conducted using the rumen simulation technique (Rusitec), as a completely randomised block design with four replications and the following four doses of GA: 0, 5, 10 and 20 mg GA/g dry matter (DM). Ethanol was used in all treatments to increase the solubilisation of GA in rumen fluid. The experimental period lasted 16 days, of which the first 7 days were for adaptation and the subsequent 9 days were for sampling. The second experiment was a 48-h batch-culture incubation conducted as a completely randomised design with a 4 (GA dose; 0, 10, 20, and 40 mg GA/g DM) × 2 (with or without ethanol) arrangement of treatments. In the Rusitec experiment, addition of GA up to 20 mg/g DM did not affect DM disappearance (DMD), organic matter (OM) disappearance, neutral detergent-fibre disappearance (NDFD), acid detergent-fibre disappearance (ADFD) or starch disappearance (P > 0.05), but crude protein disappearance was linearly decreased (P = 0.04) from 78.3% to 72.0%. Daily gas production and CH4 production expressed as mL/g DM and mL/g DMD were not affected by addition of GA (P > 0.05). Addition of GA up to 20 mg/g DM increased butyrate and isovalerate production (P < 0.05) and tended to increase isobutyrate (P = 0.09) and decrease heptanoate production (P = 0.07). In the batch-culture experiment, adding GA up to 40 mg/g DM linearly increased 48-h DMD, NDFD and ADFD (P < 0.05) and decreased (P < 0.05) CH4 expressed as mL/g DMD, mL/g NDFD and mL/g ADFD. Methane production was decreased after 24 h and 48 h only when GA was added at 10 mg/g DM without ethanol. Fermentation liquid pH and concentration of ammonia-nitrogen (ammonia-N) were also reduced (P < 0.05) with an increasing concentration of GA. Treatments with ethanol notably enhanced 48-h DMD, NDFD, ADFD, gas production (mL/g DM, mL/g OM or mL/g DMD), CH4 production (mL/g DM, mL/g DMD or mL/g NDFD), total volatile fatty acid concentration, the acetate:propionate ratio, acetate, valerate, isovalerate and caproate molar proportions (P < 0.01) and decreased propionate, butyrate and isobutyrate molar proportions (P < 0.01). Significant dose of GA × ethanol interaction was observed only for acetate molar proportion (P = 0.03). In conclusion, our study suggests that the beneficial effects of GA on feed digestion and CH4 production may be short term, while improvements in N metabolism may be sustained over the long term. It may be useful to conduct long-term in vivo studies using a range of diets and doses to verify whether GA can be used as a feed additive to mitigate enteric CH4 production and improve N metabolism of ruminants.
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Romero-Pérez A, Okine EK, Guan LL, Duval SM, Kindermann M, Beauchemin KA. Rapid Communication: Evaluation of methane inhibitor 3-nitrooxypropanol and monensin in a high-grain diet using the rumen simulation technique (Rusitec)1,2. J Anim Sci 2017. [DOI: 10.2527/jas.2017.1896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Effect of Nitrooxy Compounds with Different Molecular Structures on the Rumen Methanogenesis, Metabolic Profile, and Methanogenic Community. Curr Microbiol 2017; 74:891-898. [DOI: 10.1007/s00284-017-1261-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 05/04/2017] [Indexed: 12/17/2022]
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Guyader J, Ungerfeld EM, Beauchemin KA. Redirection of Metabolic Hydrogen by Inhibiting Methanogenesis in the Rumen Simulation Technique (RUSITEC). Front Microbiol 2017; 8:393. [PMID: 28352256 PMCID: PMC5349286 DOI: 10.3389/fmicb.2017.00393] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 02/24/2017] [Indexed: 01/08/2023] Open
Abstract
A decrease in methanogenesis is expected to improve ruminant performance by allocating rumen metabolic hydrogen ([2H]) to more energy-rendering fermentation pathways for the animal. However, decreases in methane (CH4) emissions of up to 30% are not always linked with greater performance. Therefore, the aim of this study was to understand the fate of [2H] when CH4 production in the rumen is inhibited by known methanogenesis inhibitors (nitrate, NIT; 3-nitrooxypropanol, NOP; anthraquinone, AQ) in comparison with a control treatment (CON) with the Rumen Simulation Technique (RUSITEC). Measurements started after 1 week adaptation. Substrate disappearance was not modified by methanogenesis inhibitors. Nitrate mostly seemed to decrease [2H] availability by acting as an electron acceptor competing with methanogenesis. As a consequence, NIT decreased CH4 production (-75%), dissolved dihydrogen (H2) concentration (-30%) and the percentages of reduced volatile fatty acids (butyrate, isobutyrate, valerate, isovalerate, caproate and heptanoate) except propionate, but increased acetate molar percentage, ethanol concentration and the efficiency of microbial nitrogen synthesis (+14%) without affecting gaseous H2. Nitrooxypropanol decreased methanogenesis (-75%) while increasing both gaseous and dissolved H2 concentrations (+81% and +24%, respectively). Moreover, NOP decreased acetate and isovalerate molar percentages and increased butyrate, valerate, caproate and heptanoate molar percentages as well as n-propanol and ammonium concentrations. Methanogenesis inhibition with AQ (-26%) was associated with higher gaseous H2 production (+70%) but lower dissolved H2 concentration (-76%), evidencing a lack of relationship between the two H2 forms. Anthraquinone increased ammonium concentration, caproate and heptanoate molar percentages but decreased acetate and isobutyrate molar percentages, total microbial nitrogen production and efficiency of microbial protein synthesis (-16%). Overall, NOP and AQ increased the amount of reduced volatile fatty acids, but part of [2H] spared from methanogenesis was lost as gaseous H2. Finally, [2H] recovery was similar among CON, NOP and AQ but was largely lower than 100%. Consequently, further studies are required to discover other so far unidentified [2H] sinks for a better understanding of the metabolic pathways involved in [2H] production and utilization.
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Affiliation(s)
- Jessie Guyader
- Lethbridge Research and Development Centre, Agriculture and Agri-Food CanadaLethbridge, AB, Canada
| | | | - Karen A. Beauchemin
- Lethbridge Research and Development Centre, Agriculture and Agri-Food CanadaLethbridge, AB, Canada
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Effects of 3-nitrooxypropanol and monensin on methane production using a forage-based diet in Rusitec fermenters. Anim Feed Sci Technol 2016. [DOI: 10.1016/j.anifeedsci.2016.07.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Anderson RC, Ripley LH, Bowman JGP, Callaway TR, Genovese KJ, Beier RC, Harvey RB, Nisbet DJ. Ruminal Fermentation of Anti-Methanogenic Nitrate- and Nitro-Containing Forages In Vitro. Front Vet Sci 2016; 3:62. [PMID: 27563646 PMCID: PMC4980585 DOI: 10.3389/fvets.2016.00062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 07/28/2016] [Indexed: 11/20/2022] Open
Abstract
Nitrate, 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA-, or NPOH-containing forages effectively decreased methane production, by 35–87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during the incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA, and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH and was dramatically higher, exceeding 40 μmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 μmol added formate per milliliter to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA-, and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases, higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate, and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA, and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA-, and NPOH-containing forages to achieve efficacious mitigation in ruminant methane emissions without adversely affecting fermentative efficiency or risking toxicity to animals.
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Affiliation(s)
- Robin C Anderson
- Food and Feed Safety Research Unit, United States Department of Agriculture Agricultural Research Service , College Station, TX , USA
| | - Laura H Ripley
- Food and Feed Safety Research Unit, United States Department of Agriculture Agricultural Research Service , College Station, TX , USA
| | - Jan G P Bowman
- Department of Animal and Range Sciences, Montana State University , Bozeman, MT , USA
| | - Todd R Callaway
- Food and Feed Safety Research Unit, United States Department of Agriculture Agricultural Research Service , College Station, TX , USA
| | - Kenneth J Genovese
- Food and Feed Safety Research Unit, United States Department of Agriculture Agricultural Research Service , College Station, TX , USA
| | - Ross C Beier
- Food and Feed Safety Research Unit, United States Department of Agriculture Agricultural Research Service , College Station, TX , USA
| | - Roger B Harvey
- Food and Feed Safety Research Unit, United States Department of Agriculture Agricultural Research Service , College Station, TX , USA
| | - David J Nisbet
- Food and Feed Safety Research Unit, United States Department of Agriculture Agricultural Research Service , College Station, TX , USA
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Lopes JC, de Matos LF, Harper MT, Giallongo F, Oh J, Gruen D, Ono S, Kindermann M, Duval S, Hristov AN. Effect of 3-nitrooxypropanol on methane and hydrogen emissions, methane isotopic signature, and ruminal fermentation in dairy cows. J Dairy Sci 2016; 99:5335-5344. [PMID: 27085412 DOI: 10.3168/jds.2015-10832] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2015] [Accepted: 03/08/2016] [Indexed: 11/19/2022]
Abstract
The objective of this crossover experiment was to investigate the effect of a methane inhibitor, 3-nitrooxypropanol (3NOP), on enteric methane emission, methane isotopic composition, and rumen fermentation and microbial profile in lactating dairy cows. The experiment involved 6 ruminally cannulated late-lactation Holstein cows assigned to 2 treatments: control and 3NOP (60 mg/kg of feed dry matter). Compared with the control, 3NOP decreased methane emission by 31% and increased hydrogen emission from undetectable to 1.33 g/d. Methane emissions per kilogram of dry matter intake and milk yield were also decreased 34% by 3NOP. Milk production and composition were not affected by 3NOP, except milk fat concentration was increased compared with the control. Concentrations of total VFA and propionate in ruminal fluid were not affected by treatment, but acetate concentration tended to be lower and acetate-to-propionate ratio was lower for 3NOP compared with the control. The 3NOP decreased the molar proportion of acetate and increase those of propionate, butyrate, valerate, and isovalerate. Deuterium-to-hydrogen ratios of methane and the abundance of (13)CH3D were similar between treatments. Compared with the control, minor (4‰) depletion in the (13)C/(12)C ratio was observed for 3NOP. Genus composition of methanogenic archaea (Methanobrevibacter, Methanosphaera, and Methanomicrobium) was not affected by 3NOP, but the proportion of methanogens in the total cell counts tended to be decreased by 3NOP. Prevotella spp., the predominant bacterial genus in ruminal contents in this experiment, was also not affected by 3NOP. Compared with the control, Ruminococcus and Clostridium spp. were decreased and Butyrivibrio spp. was increased by 3NOP. This experiment demonstrated that a substantial inhibition of enteric methane emission by 3NOP in dairy cows was accompanied with increased hydrogen emission and decreased acetate-to-propionate ratio; however, neither an effect on rumen archaeal community composition nor a significant change in the isotope composition of methane was observed.
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Affiliation(s)
- J C Lopes
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - L F de Matos
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - M T Harper
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - F Giallongo
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - J Oh
- Department of Animal Science, The Pennsylvania State University, University Park 16802
| | - D Gruen
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge 02139
| | - S Ono
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge 02139
| | - M Kindermann
- DSM Nutritional Products, Animal Nutrition and Health, Basel, Switzerland CH-4002
| | - S Duval
- DSM Nutritional Products France, Research Centre for Animal Nutrition and Health, Saint Louis Cedex, France 68305
| | - A N Hristov
- Department of Animal Science, The Pennsylvania State University, University Park 16802.
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Latham EA, Anderson RC, Pinchak WE, Nisbet DJ. Insights on Alterations to the Rumen Ecosystem by Nitrate and Nitrocompounds. Front Microbiol 2016; 7:228. [PMID: 26973609 PMCID: PMC4777734 DOI: 10.3389/fmicb.2016.00228] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 02/12/2016] [Indexed: 11/13/2022] Open
Abstract
Nitrate and certain short chain nitrocompounds and nitro-oxy compounds are being investigated as dietary supplements to reduce economic and environmental costs associated with ruminal methane emissions. Thermodynamically, nitrate is a preferred electron acceptor in the rumen that consumes electrons at the expense of methanogenesis during dissimilatory reduction to an intermediate, nitrite, which is primarily reduced to ammonia although small quantities of nitrous oxide may also be produced. Short chain nitrocompounds act as direct inhibitors of methanogenic bacteria although certain of these compounds may also consume electrons at the expense of methanogenesis and are effective inhibitors of important foodborne pathogens. Microbial and nutritional consequences of incorporating nitrate into ruminant diets typically results in increased acetate production. Unlike most other methane-inhibiting supplements, nitrate decreases or has no effect on propionate production. The type of nitrate salt added influences rates of nitrate reduction, rates of nitrite accumulation and efficacy of methane reduction, with sodium and potassium salts being more potent than calcium nitrate salts. Digestive consequences of adding nitrocompounds to ruminant diets are more variable and may in some cases increase propionate production. Concerns about the toxicity of nitrate's intermediate product, nitrite, to ruminants necessitate management, as animal poisoning may occur via methemoglobinemia. Certain of the naturally occurring nitrocompounds, such as 3-nitro-1-propionate or 3-nitro-1-propanol also cause poisoning but via inhibition of succinate dehydrogenase. Typical risk management procedures to avoid nitrite toxicity involve gradually adapting the animals to higher concentrations of nitrate and nitrite, which could possibly be used with the nitrocompounds as well. A number of organisms responsible for nitrate metabolism in the rumen have been characterized. To date a single rumen bacterium is identified as contributing appreciably to nitrocompound metabolism. Appropriate doses of the nitrocompounds and nitrate, singly or in combination with probiotic bacteria selected for nitrite and nitrocompound detoxification activity promise to alleviate risks of toxicity. Further studies are needed to more clearly define benefits and risk of these technologies to make them saleable for livestock producers.
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Affiliation(s)
- Elizabeth A. Latham
- Department of Animal Science, Texas A&M UniversityCollege Station, TX, USA
- Texas A&M AgriLife ResearchVernon, TX, USA
| | - Robin C. Anderson
- Food and Feed Safety Research Unit, Southern Plains Agricultural Research Center, United States Department of Agriculture, Agricultural Research ServiceCollege Station, TX, USA
| | | | - David J. Nisbet
- Food and Feed Safety Research Unit, Southern Plains Agricultural Research Center, United States Department of Agriculture, Agricultural Research ServiceCollege Station, TX, USA
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