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REVIEW

Potential solutions to the major greenhouse-gas issues facing Australasian dairy farming

R. J. Eckard A C and H. Clark B
+ Author Affiliations
- Author Affiliations

A Faculty of Veterinary and Agricultural Science, The University of Melbourne, Parkville, Vic. 3010, Australia.

B New Zealand Agricultural Greenhouse Gas Research Centre, Grasslands Research Centre, Tennent Drive, Palmerston North 4442, New Zealand.

C Corresponding author. Email: Richard.Eckard@unimelb.edu.au

Animal Production Science 60(1) 10-16 https://doi.org/10.1071/AN18574
Submitted: 10 September 2018  Accepted: 20 November 2018   Published: 21 December 2018

Abstract

The Australasian dairy industry is facing the dual challenges of increasing productivity, while also reducing its emissions of the greenhouse gases (GHG) methane and nitrous oxide. Following the COP21 Paris Agreement, all sectors of the economy will be expected to contribute to GHG abatement. Enteric methane is the major source of GHG emissions from dairy production systems (>70%), followed by nitrous oxide (13%) and methane (12%) from animal waste, with nitrogen (N)-fertiliser use contributing ~3.5% of total on-farm non-carbon dioxide equivalent (non-CO2e) emissions. Research on reducing methane emissions from dairy cattle has focussed on feeding dietary supplements (e.g. tannins, dietary oils and wheat), rumen modification (e.g. vaccine, inhibitors), breeding and animal management. Research on reducing nitrous oxide emissions has focussed on improving N fertiliser efficiency and reducing urinary N loss. Profitable options for significant abatement on farm are still limited, with the industry focusing instead on improving production efficiency, while reducing emission intensity (t CO2e/t product). Absolute emission reduction will become an imperative as the world moves towards carbon neutrality by 2050 and, thus, a priority for research. However, even with implementation of best-practice abatement, it is likely that some residual emissions will remain in the foreseeable future. The soil organic carbon content of dairy soils under well fertilised, high-rainfall or irrigated permanent pastures are already high, therefore limiting the potential for further soil carbon sequestration as an offset against these residual emissions. The Australasian dairy industry will, therefore, also need to consider how these residual emissions will be offset through carbon sequestration mainly in trees and, to a more limited extent, increasing soil organic carbon.

Additional keywords: carbon sequestration, enteric methane, milk production, mitigation, nitrogen fertiliser, urine.


References

Browne NA, Behrendt R, Kingwell RS, Eckard RJ (2015) Does producing more product over a lifetime reduce greenhouse gas emissions and increase profitability in dairy and wool enterprises? Animal Production Science 55, 49–55.
Does producing more product over a lifetime reduce greenhouse gas emissions and increase profitability in dairy and wool enterprises?Crossref | GoogleScholarGoogle Scholar |

Cabezas-Garcia EH, Krizsan SJ, Shingfield KJ, Huhtanen P (2017) Between-cow variation in digestion and rumen fermentation variables associated with methane production. Journal of Dairy Science 100, 4409–4424.
Between-cow variation in digestion and rumen fermentation variables associated with methane production.Crossref | GoogleScholarGoogle Scholar |

Chen D, Suter H, Islam A, Edis R, Freney JR, Walker CN (2008) Prospects of improving efficiency of fertiliser nitrogen in Australian agriculture: a review of enhanced efficiency fertilisers. Soil Research 46, 289–301.
Prospects of improving efficiency of fertiliser nitrogen in Australian agriculture: a review of enhanced efficiency fertilisers.Crossref | GoogleScholarGoogle Scholar |

Christie KM, Rawnsley RP, Harrison MT, Eckard RJ (2014) Using a modelling approach to evaluate two options for improving animal nitrogen use efficiency and reducing nitrous oxide emissions on dairy farms in southern Australia. Animal Production Science 54, 1960–1970.
Using a modelling approach to evaluate two options for improving animal nitrogen use efficiency and reducing nitrous oxide emissions on dairy farms in southern Australia.Crossref | GoogleScholarGoogle Scholar |

Christie KM, Rawnsley RP, Phelps C, Eckard RJ (2018a) Revised greenhouse-gas emissions from Australian dairy farms following application of updated methodology. Animal Production Science 58, 937–942.
Revised greenhouse-gas emissions from Australian dairy farms following application of updated methodology.Crossref | GoogleScholarGoogle Scholar |

Christie KM, Smith AP, Rawnsley RP, Harrison MT, Eckard RJ (2018b) Simulated seasonal responses of grazed dairy pastures to nitrogen fertilizer in SE Australia: pasture production. Agricultural Systems 166, 36–47.
Simulated seasonal responses of grazed dairy pastures to nitrogen fertilizer in SE Australia: pasture production.Crossref | GoogleScholarGoogle Scholar |

Clark H (2013) Nutritional and host effects on methanogenesis in the grazing ruminant. Animal 7, 41–48.
Nutritional and host effects on methanogenesis in the grazing ruminant.Crossref | GoogleScholarGoogle Scholar |

Clark CEF, McLeod KLM, Glassey CB, Gregorini P, Costall DA, Betteridge K, Jago JG (2010) Capturing urine while maintaining pasture intake, milk production, and animal welfare of dairy cows in early and late lactation. Journal of Dairy Science 93, 2280–2286.
Capturing urine while maintaining pasture intake, milk production, and animal welfare of dairy cows in early and late lactation.Crossref | GoogleScholarGoogle Scholar |

Cottle DJ, Nolan JV, Wiedemann SG (2011) Ruminant enteric methane mitigation: a review. Animal Production Science 51, 491–514.
Ruminant enteric methane mitigation: a review.Crossref | GoogleScholarGoogle Scholar |

Cullen BR, Johnson IR, Eckard RJ, Lodge GM, Walker RG, Rawnsley RP, McCaskill MR (2009) Climate change effects on pasture systems in south-eastern Australia. Crop and Pasture Science 60, 933–942.
Climate change effects on pasture systems in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |

de Klein CAM, Eckard RJ (2008) Targeted technologies for nitrous oxide abatement from animal agriculture. Australian Journal of Experimental Agriculture 48, 14–20.
Targeted technologies for nitrous oxide abatement from animal agriculture.Crossref | GoogleScholarGoogle Scholar |

de Klein CAM, Eckard RJ, van der Weerden TJ (2010) Chapter 6: nitrous oxide emissions from the nitrogen cycle in livestock agriculture: estimation and mitigation. In ‘Nitrous oxide and climate change’. (Ed. K Smith) pp. 107–144. (Earthscan Publications, University of Edinburgh: Edinburgh, UK)

Di H, Cameron K, Sherlock R, Shen J-P, He J-Z, Winefield C (2010) Nitrous oxide emissions from grazed grassland as affected by a nitrification inhibitor, dicyandiamide, and relationships with ammonia-oxidizing bacteria and archaea. Journal of Soils and Sediments 10, 943–954.
Nitrous oxide emissions from grazed grassland as affected by a nitrification inhibitor, dicyandiamide, and relationships with ammonia-oxidizing bacteria and archaea.Crossref | GoogleScholarGoogle Scholar |

Doran-Browne NA, Ive J, Graham P, Eckard RJ (2016) Carbon-neutral wool farming in south-eastern Australia. Animal Production Science 56, 417–422.
Carbon-neutral wool farming in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Doran-Browne N, Wootton M, Taylor C, Eckard R (2018) Offsets required to reduce the carbon balance of sheep and beef farms through carbon sequestration in trees and soils. Animal Production Science 58, 1648–1655.
Offsets required to reduce the carbon balance of sheep and beef farms through carbon sequestration in trees and soils.Crossref | GoogleScholarGoogle Scholar |

Dougherty WJ, Collins D, Van Zwieten L, Rowlings DW (2016) Nitrification (DMPP) and urease (NBPT) inhibitors had no effect on pasture yield, nitrous oxide emissions, or nitrate leaching under irrigation in a hot-dry climate. Soil Research 54, 675–683.
Nitrification (DMPP) and urease (NBPT) inhibitors had no effect on pasture yield, nitrous oxide emissions, or nitrate leaching under irrigation in a hot-dry climate.Crossref | GoogleScholarGoogle Scholar |

Duval S, Kindermann M (2012) Use of nitrooxy organic molecules in feed for reducing enteric methane emissions in ruminants, and/or to improve ruminant performance. World Intellectual Property Organization. International Patent Application WO 2012/084629 A1.

Eckard R, Cullen B (2011) Impacts of future climate scenarios on nitrous oxide emissions from pasture based dairy systems in south eastern Australia. Animal Feed Science and Technology 166–167, 736–748.
Impacts of future climate scenarios on nitrous oxide emissions from pasture based dairy systems in south eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Eckard RJ, Grainger CJ, de Klein CAM (2010) Options for the abatement of methane and nitrous oxide from ruminant production – a review. Livestock Science 130, 47–56.
Options for the abatement of methane and nitrous oxide from ruminant production – a review.Crossref | GoogleScholarGoogle Scholar |

Fonterra (2017) Sustainability report for the year ending 31 July 2017. 105. Available at https://view.publitas.com/fonterra/sustainability-report-2017 [Verified 26 November 2018]

Gerber PJ, Hristov AN, Henderson B, Makkar H, Oh J, Lee C, Meinen R, Montes F, Ott T, Firkins J, Rotz A, Dell C, Adesogan AT, Yang WZ, Tricarico JM, Kebreab E, Waghorn G, Dijkstra J, Oosting S (2013) Technical options for the mitigation of direct methane and nitrous oxide emissions from livestock: a review. Animal 7, 220–234.
Technical options for the mitigation of direct methane and nitrous oxide emissions from livestock: a review.Crossref | GoogleScholarGoogle Scholar |

Grainger C, Beauchemin KA (2011) Can enteric methane emissions from ruminants be lowered without lowering their production? Animal Feed Science and Technology 166–167, 308–320.
Can enteric methane emissions from ruminants be lowered without lowering their production?Crossref | GoogleScholarGoogle Scholar |

Grainger C, Clarke T, Auldist MJ, Beauchemin KA, McGinn SM, Waghorn GC, Eckard RJ (2009) Potential use of Acacia mearnsii condensed tannins to reduce methane emissions and nitrogen excretion from grazing dairy cows. Canadian Journal of Animal Science 89, 241–251.
Potential use of Acacia mearnsii condensed tannins to reduce methane emissions and nitrogen excretion from grazing dairy cows.Crossref | GoogleScholarGoogle Scholar |

Henry B, Charmley E, Eckard R, Gaughan JB, Hegarty R (2012) Livestock production in a changing climate: adaptation and mitigation research in Australia. Crop and Pasture Science 63, 191–202.
Livestock production in a changing climate: adaptation and mitigation research in Australia.Crossref | GoogleScholarGoogle Scholar |

Hristov AN, Oh J, Firkins JL, Dijkstra J, Kebreab E, Waghorn G, Makkar HPS, Adesogan AT, Yang W, Lee C, Gerber PJ, Henderson B, Tricarico JM (2013) Special topics: mitigation of methane and nitrous oxide emissions from animal operations: I. A review of enteric methane mitigation options. Journal of Animal Science 91, 5045–5069.
Special topics: mitigation of methane and nitrous oxide emissions from animal operations: I. A review of enteric methane mitigation options.Crossref | GoogleScholarGoogle Scholar |

Hristov AN, Oh J, Giallongo F, Frederick TW, Harper MT, Weeks HL, Branco AF, Moate PJ, Deighton MH, Williams SRO, Kindermann M, Duval S (2015) An inhibitor persistently decreased enteric methane emission from dairy cows with no negative effect on milk production. Proceedings of the National Academy of Sciences of the United States of America 112, 10663–10668.
An inhibitor persistently decreased enteric methane emission from dairy cows with no negative effect on milk production.Crossref | GoogleScholarGoogle Scholar |

Jonker A, Scobie D, Dynes R, Edwards G, De Klein C, Hague H, McAuliffe R, Taylor A, Knight T, Waghorn G (2017) Feeding diets with fodder beet decreased methane emissions from dry and lactating dairy cows in grazing systems. Animal Production Science 57, 1445–1450.
Feeding diets with fodder beet decreased methane emissions from dry and lactating dairy cows in grazing systems.Crossref | GoogleScholarGoogle Scholar |

Jonker A, Hickey SM, Rowe SJ, Janssen PH, Shackell GH, Elmes S, Bain WE, Wing J, Greer GJ, Bryson B, MacLean S, Dodds KG, Pinares-Patiño CS, Young EA, Knowler K, Pickering NK, McEwan JC (2018a) Genetic parameters of methane emissions determined using portable accumulation chambers in lambs and ewes grazing pasture and genetic correlations with emissions determined in respiration chambers1. Journal of Animal Science 96, 3031–3042.
Genetic parameters of methane emissions determined using portable accumulation chambers in lambs and ewes grazing pasture and genetic correlations with emissions determined in respiration chambers1.Crossref | GoogleScholarGoogle Scholar |

Jonker A, Molano G, Sandoval E, Taylor PS, Antwi C, Olinga S, Cosgrove GP (2018b) Methane emissions differ between sheep offered a conventional diploid, a high-sugar diploid or a tetraploid perennial ryegrass cultivar at two allowances at three times of the year. Animal Production Science 58, 1043–1048.
Methane emissions differ between sheep offered a conventional diploid, a high-sugar diploid or a tetraploid perennial ryegrass cultivar at two allowances at three times of the year.Crossref | GoogleScholarGoogle Scholar |

Leddin CM, Ho CKM, Dalton W (2012) Generating saleable carbon offsets from dairy farm systems. In ‘Proceedings of the 5th Australasian dairy science symposium’, 13–15 November 2012, Melbourne, Vic., Australia. (Ed. J Jacobs) pp. 180–183. (The Australasian Dairy Science Symposium Committee: Melbourne)

Li X, Norman HC, Kinley RD, Laurence M, Wilmot M, Bender H, de Nys R, Tomkins N (2018) Asparagopsis taxiformis decreases enteric methane production from sheep. Animal Production Science 58, 681–688.
Asparagopsis taxiformis decreases enteric methane production from sheep.Crossref | GoogleScholarGoogle Scholar |

Machado L, Magnusson M, Paul NA, de Nys R, Tomkins N (2014) Effects of marine and freshwater macroalgae on in vitro total gas and methane production. PLoS One 9, e85289
Effects of marine and freshwater macroalgae on in vitro total gas and methane production.Crossref | GoogleScholarGoogle Scholar |

Martin C, Morgavi DP, Doreau M (2010) Methane mitigation in ruminants: from microbe to the farm scale. Animal 4, 351–365.
Methane mitigation in ruminants: from microbe to the farm scale.Crossref | GoogleScholarGoogle Scholar |

Meinshausen M, Alexander R (2017) ‘NDC factsheet: Fiji. COP23 edition.’ Available at www.climatecollege.unimelb.edu.au/indc-factsheets [Verified 26 November 2018]

Meyer RS, Cullen BR, Whetton PH, Robertson FA, Eckard RJ (2018) Potential impacts of climate change on soil organic carbon and productivity in pastures of south eastern Australia. Agricultural Systems 167, 34–46.
Potential impacts of climate change on soil organic carbon and productivity in pastures of south eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Ministry for the Environment (2017) New Zealand’s third biennial report under the United Nations Framework Convention on Climate Change. Available at www.mfe.govt.nz/publications/climate-change/new-zealands-third-biennial-report-under-united-nations-framework [Verified 26 November 2018]

Moate P, Williams S, Grainger C, Hannah M, Ponnampalam E, Eckard R (2011) Influence of cold-pressed canola, brewers grains and hominy meal as dietary supplements suitable for reducing enteric methane emissions from lactating dairy cows. Animal Feed Science and Technology 166–167, 254–264.
Influence of cold-pressed canola, brewers grains and hominy meal as dietary supplements suitable for reducing enteric methane emissions from lactating dairy cows.Crossref | GoogleScholarGoogle Scholar |

Moate PJ, Williams SRO, Hannah MC, Eckard RJ, Auldist MJ, Ribaux BE, Jacobs JL, Wales WJ (2013) Effects of feeding algal meal high in docosahexaenoic acid on feed intake, milk production, and methane emissions in dairy cows. Journal of Dairy Science 96, 3177–3188.
Effects of feeding algal meal high in docosahexaenoic acid on feed intake, milk production, and methane emissions in dairy cows.Crossref | GoogleScholarGoogle Scholar |

Moate PJ, Williams SRO, Deighton MH, Pryce JE, Hayes BJ, Jacobs JL, Eckard RJ, Hannah MC, Wales WJ (2014a) Mitigation of enteric methane emissions from the Australian dairy industry. In ‘Proceedings of the 5th Australasian dairy science symposium’, 19–21 November 2014, Hamilton, New Zealand. (Ed. J Roche) pp. 121–140. (The Australasian Dairy Science Symposium Committee: Hamilton New Zealand)

Moate PJ, Williams SRO, Torok VA, Hannah MC, Ribaux BE, Tavendale MH, Eckard RJ, Jacobs JL, Auldist MJ, Wales WJ (2014b) Grape marc reduces methane emissions when fed to dairy cows. Journal of Dairy Science 97, 5073–5087.
Grape marc reduces methane emissions when fed to dairy cows.Crossref | GoogleScholarGoogle Scholar |

Moate PJ, Deighton MH, Williams SRO, Pryce JE, Hayes BJ, Jacobs JL, Eckard RJ, Hannah MC, Wales WJ (2016) Reducing the carbon footprint of Australian milk production by mitigation of enteric methane emissions. Animal Production Science 56, 1017–1034.
Reducing the carbon footprint of Australian milk production by mitigation of enteric methane emissions.Crossref | GoogleScholarGoogle Scholar |

Moate PJ, Williams SRO, Jacobs JL, Hannah MC, Beauchemin KA, Eckard RJ, Wales WJ (2017) Wheat is more potent than corn or barley for dietary mitigation of enteric methane emissions from dairy cows. Journal of Dairy Science 100, 7139–7153.
Wheat is more potent than corn or barley for dietary mitigation of enteric methane emissions from dairy cows.Crossref | GoogleScholarGoogle Scholar |

Moate PJ, Jacobs JL, Hannah MC, Morris GL, Beauchemin KA, Alvarez Hess PS, Eckard RJ, Liu Z, Rochfort S, Wales WJ, Williams SRO (2018) Adaptation responses in milk fat yield and methane emissions of dairy cows when wheat was included in their diet for 16 weeks. Journal of Dairy Science 101, 7117–7132.
Adaptation responses in milk fat yield and methane emissions of dairy cows when wheat was included in their diet for 16 weeks.Crossref | GoogleScholarGoogle Scholar |

Nauer PA, Fest BJ, Visser L, Arndt SK (2018) On-farm trial on the effectiveness of the nitrification inhibitor DMPP indicates no benefits under commercial Australian farming practices. Agriculture, Ecosystems & Environment 253, 82–89.
On-farm trial on the effectiveness of the nitrification inhibitor DMPP indicates no benefits under commercial Australian farming practices.Crossref | GoogleScholarGoogle Scholar |

Pinares-Patiño CS, Hickey SM, Young EA, Dodds KG, MacLean S, Molano G, Sandoval E, Kjestrup H, Harland R, Hunt C, Pickering NK, McEwan JC (2013) Heritability estimates of methane emissions from sheep. Animal 7, 316–321.
Heritability estimates of methane emissions from sheep.Crossref | GoogleScholarGoogle Scholar |

Reisinger A, Clark H (2016) Modelling agriculture’s contribution to New Zealand’s contribution to the post-2020 agreement. A report prepared for the New Zealand Ministry of Primary Industries, MPI Information Paper No: 2016/02. Available at https://mpi.govt.nz/dmsdocument/11362-modelling-agricultures-contribution-to-new-zealands-contribution-to-the-post-2020-agreement [Verified 6 December 2018]

Reisinger, A, Clark, H, Journeaux, P, Clark, D, Lambert, G (2017) On-farm options to reduce agricultural GHG emissions in New Zealand. A report to the Biological Emissions Reference Group. Available at https://www.mpi.govt.nz/dmsdocument/32158-berg-current-mitigaiton-potential-final [Verified 6 December 2018]

Reisinger, A, Clark, H, Abercrombie, R, Aspin, M, Ettema, P, Harris, M, Hoggard, A, Newman, M, Sneath, G (2018) Future options to reduce biological GHG emissions on-farm: critical assumptions and national-scale impact. A report to the Biological Emissions Reference Group. Available at https://www.mpi.govt.nz/dmsdocument/32128-berg-report-future-options-final-dec-2018 [Verified 6 December 2018]

Richards M, Bruun TB, Campbell B, Gregersen LE, Huyer S, Kuntze V, Madsen STN, Oldvig MB, Vasileiou I (2016) How countries plan to address agricultural adaptation and mitigation: an analysis of intended nationally determined contributions. CCAFS dataset version 1.2. Available at http://hdl.handle.net/10568/73255 [Verified 26 November 2018]

Rowlings DW, Scheer C, Liu S, Grace PR (2016) Annual nitrogen dynamics and urea fertilizer recoveries from a dairy pasture using 15N; effect of nitrification inhibitor DMPP and reduced application rates. Agriculture, Ecosystems & Environment 216, 216–225.
Annual nitrogen dynamics and urea fertilizer recoveries from a dairy pasture using 15N; effect of nitrification inhibitor DMPP and reduced application rates.Crossref | GoogleScholarGoogle Scholar |

Schipper L, Sparling G (2011) Accumulation of soil organic C and change in C : N ratio after establishment of pastures on reverted scrubland in New Zealand. Biogeochemistry 104, 49–58.
Accumulation of soil organic C and change in C : N ratio after establishment of pastures on reverted scrubland in New Zealand.Crossref | GoogleScholarGoogle Scholar |

Schipper LA, Mudge PL, Kirschbaum MUF, Hedley CB, Golubiewski NE, Smaill SJ, Kelliher FM (2017) A review of soil carbon change in New Zealand’s grazed grasslands. New Zealand Journal of Agricultural Research 60, 93–118.
A review of soil carbon change in New Zealand’s grazed grasslands.Crossref | GoogleScholarGoogle Scholar |

Smith AP, Christie KM, Rawnsley RP, Eckard RJ (2018) Fertiliser strategies for improving nitrogen use efficiency in grazed dairy pastures. Agricultural Systems 165, 274–282.
Fertiliser strategies for improving nitrogen use efficiency in grazed dairy pastures.Crossref | GoogleScholarGoogle Scholar |

Subharat S, Shu D, Zheng T, Buddle BM, Kaneko K, Hook S, Janssen PH, Wedlock DN (2016) Vaccination of sheep with a methanogen protein provides insight into levels of antibody in saliva needed to target ruminal methanogens. PLoS One 11, e0159861
Vaccination of sheep with a methanogen protein provides insight into levels of antibody in saliva needed to target ruminal methanogens.Crossref | GoogleScholarGoogle Scholar |

Sun X, Henderson G, Cox F, Molano G, Harrison SJ, Luo D, Janssen PH, Pacheco D (2015) Lambs fed fresh winter forage rape (Brassica napus l.) emit less methane than those fed perennial ryegrass (Lolium perenne l.), and possible mechanisms behind the difference. PLoS One 10, e0119697
Lambs fed fresh winter forage rape (Brassica napus l.) emit less methane than those fed perennial ryegrass (Lolium perenne l.), and possible mechanisms behind the difference.Crossref | GoogleScholarGoogle Scholar |

Suter HC, Sultana H, Davies R, Walker C, Chen D (2016) Influence of enhanced efficiency fertilisation techniques on nitrous oxide emissions and productivity response from urea in a temperate Australian ryegrass pasture. Soil Research 54, 523–532.
Influence of enhanced efficiency fertilisation techniques on nitrous oxide emissions and productivity response from urea in a temperate Australian ryegrass pasture.Crossref | GoogleScholarGoogle Scholar |

UNFCCC (2015a) ‘Adoption of the Paris Agreement. FCCC/CP/ 2015/L.9/Rev.1 39.’ Available at https://unfccc.int/resource/docs/2015/cop21/eng/l09r01.pdf [Verified 26 November 2018]

UNFCCC (2015b) ‘Adoption of the Paris Agreement. United Nations/framework convention on climate change, 21st conference of the Parties FCCC/CP/2015/L.9/Rev.1.’ Available at https://unfccc.int/resource/docs/2015/cop21/eng/l09r01.pdf [Verified 26 November 2018]

Unilever (2010) Making sustainable living commonplace. Unilever annual report and accounts 2017 182. Available at https://www.unilever.com/Images/unilever-annual-report-and-accounts-2017_tcm244-516456_en. pdf [Verified 26 November 2018]

Van Nevel CJ, Demeyer DI (1996) Control of rumen methanogenesis. Environmental Monitoring and Assessment 42, 73–97.
Control of rumen methanogenesis.Crossref | GoogleScholarGoogle Scholar |

Veneman JB, Muetzel S, Hart KJ, Faulkner CL, Moorby JM, Perdok HB, Newbold CJ (2015) Does dietary mitigation of enteric methane production affect rumen function and animal productivity in dairy cows? PLoS One 10, e0140282
Does dietary mitigation of enteric methane production affect rumen function and animal productivity in dairy cows?Crossref | GoogleScholarGoogle Scholar |

Whitehead D, Schipper LA, Pronger J, Moinet GYK, Mudge PL, Calvelo Pereira R, Kirschbaum MUF, McNally SR, Beare MH, Camps-Arbestain M (2018) Management practices to reduce losses or increase soil carbon stocks in temperate grazed grasslands: New Zealand as a case study. Agriculture, Ecosystems & Environment 265, 432–443.
Management practices to reduce losses or increase soil carbon stocks in temperate grazed grasslands: New Zealand as a case study.Crossref | GoogleScholarGoogle Scholar |

Williams SRO, Fisher PD, Berrisford T, Moate PJ, Reynard K (2014) Reducing methane on-farm by feeding diets high in fat may not always reduce life cycle greenhouse gas emissions. The International Journal of Life Cycle Assessment 19, 69–78.
Reducing methane on-farm by feeding diets high in fat may not always reduce life cycle greenhouse gas emissions.Crossref | GoogleScholarGoogle Scholar |

Yáñez-Ruiz DR, Abecia L, Newbold CJ (2015) Manipulating rumen microbiome and fermentation through interventions during early life: a review. Frontiers in Microbiology 6,
Manipulating rumen microbiome and fermentation through interventions during early life: a review.Crossref | GoogleScholarGoogle Scholar |