Animal Production Science Animal Production Science Society
Food, fibre and pharmaceuticals from animals
RESEARCH ARTICLE

Modelling enteric methane abatement from earlier mating of dairy heifers in subtropical Australia by improving diet quality

K. M. Christie A D , M. T. Harrison A , L. M. Trevaskis B , R. P. Rawnsley A and R. J. Eckard C
+ Author Affiliations
- Author Affiliations

A Tasmanian Institute of Agriculture, University of Tasmania, Burnie, Tas. 7320, Australia.

B Emmanuel College, University of Queensland, St Lucia, Qld 4067, Australia.

C Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Vic. 3010, Australia.

D Corresponding author. Email: Karen.Christie@utas.edu.au

Animal Production Science 56(3) 565-573 https://doi.org/10.1071/AN15296
Submitted: 11 June 2015  Accepted: 28 October 2015   Published: 9 February 2016

Abstract

Milking cows typically dominate dairy farm greenhouse gas (GHG) emissions, but replacement heifers also contribute to farm emissions and can increase the emission intensity of milk production. In northern Australia, heifers generally graze poorer-quality subtropical pastures and in the absence of energy-dense supplementary feed during periods of low pasture growth, liveweight (LW) gain can be restricted. This modelling study examined the time required and enteric methane (CH4) emissions produced in raising dairy heifers to a target LW for first mating by feeding a diet assuming either constant (static) or variable (dynamic) nutritive values. Using a static approach (Australian Feeding Standards methodology), and assuming a target mating LW of 360 kg, growing heifers reached their target LW at ~18 months of age while consuming C4 grasses with a constant metabolisable energy content of 9.5 MJ/kg dry matter (DM) or 11 months of age on a diet of 11.0 MJ/kg DM. Enteric CH4 emissions were 1.2 and 0.8 t of carbon dioxide equivalents/heifer over the 18- and 11-month periods, respectively. To explore the extent with which climatic conditions influence seasonal pasture availability and nutritive value with a dynamic approach, we used a whole-farm biophysical model (SGS pasture model) to simulate diets with mean metabolisable energy values of 9.5 and 10.9 MJ/ kg DM. On average (±s.d.), heifers required 22 ± 4 and 17 ± 1 months, respectively, to reach target LW, with cumulative enteric CH4 emissions of 1.22 ± 0.20 and 0.72 ± 0.04 t carbon dioxide equivalents, respectively. The dynamic approach resulted in slower LW gain due to the variable nutritive value of the diet throughout the year, resulting in seasonal periods of LW plateauing or decline. Maintaining heifers on high-quality diets in subtropical northern Australia should result in increased daily LW gain, lower enteric CH4 emissions to mating LW and earlier calving. Together, these factors reduce their lifetime emission intensity of milk production.

Additional keywords: greenhouse gas emissions, liveweight gain, SGS pasture model, subtropical pastures.


References

Australian Dairy Industry Council (2013) Australian Dairy Industry Sustainability Framework progress report 2013. Dairy Australia, Melbourne. Available at http://www.dairyaustralia.com.au/~/media/Documents/Industry%20overview/Sustainability/CC-537%20Dairy%2012pg_web_2.pdf [Verified 19 May 2014]

Bauman DE, McCutcheon SN, Steinhour WD, Eppard PJ, Sechen SJ (1985) Sources of variation and prospects for improvement of productive efficiency in the dairy cow. Journal of Animal Science 60, 583–592.

Bell MJ, Eckard RJ, Harrison MT, Neal JS, Cullen BR (2013) Effect of warming on the productivity of perennial ryegrass and kikuyu pastures in south-eastern Australia. Crop and Pasture Science 64, 61–70.
Effect of warming on the productivity of perennial ryegrass and kikuyu pastures in south-eastern Australia.CrossRef |

Botha PR, Meeske R, Snyman HA (2008) Kikuyu over-sown with ryegrass and clover: dry matter production, botanical composition and nutritional value. African Journal of Range & Forage Science 25, 93–101.
Kikuyu over-sown with ryegrass and clover: dry matter production, botanical composition and nutritional value.CrossRef |

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 | 1:CAS:528:DC%2BC2cXhvVGgsb7N&md5=80288e73d3ea6446136e805c066465dcCAS |

Cowan RT, O’Grady P, Moss RJ (1974) Relationship of age and live weight at first calving to subsequent yields of Friesian heifers grazing tropical pastures in Queensland. Queensland Journal of Agricultural and Animal Sciences 31, 367–370.

CSIRO (2007) ‘Nutrient requirements of domesticated ruminants.’ (CSIRO Publishing: Melbourne)

Cullen BR, Eckard RJ, Callow MN, Johnson IR, Chapman DF, Rawnsley RP, Garcia SC, White T, Snow VO (2008) Simulating pasture growth rates in Australian and New Zealand grazing systems. Australian Journal of Agricultural Research 59, 761–768.
Simulating pasture growth rates in Australian and New Zealand grazing systems.CrossRef |

Dairy Australia (2003) ‘The InCalf book for dairy farmers.’ (Dairy Australia: Melbourne)

Department of Climate Change and Energy Efficiency (2012) Australian National Greenhouse Accounts, National Inventory Report 2010. The Australian Government Submission to the UN Framework Convention on Climate Change April 2012. Vol. 1. Department of Climate Change and Energy Efficiency, Canberra.

Dobos RC, Nandra KS, Riley K, Fulkerson WJ, Lean IJ, Kellaway RC (2001) Effects of age and liveweight at first calving on first lactation milk, protein and fat yield of Friesian heifers. Australian Journal of Experimental Agriculture 41, 13–19.
Effects of age and liveweight at first calving on first lactation milk, protein and fat yield of Friesian heifers.CrossRef |

Dobos RC, Nandra KS, Riley K, Fulkerson WJ, Alford A, Lean IJ (2004) Effects of age and liveweight of dairy heifers at first calving on multiple lactation production. Australian Journal of Experimental Agriculture 44, 969–974.
Effects of age and liveweight of dairy heifers at first calving on multiple lactation production.CrossRef |

Doran-Browne NA, Bray SG, Johnson IR, O’Reagain PJ, Eckard RJ (2014) Northern Australian pasture and beef systems. 2. Validation and use of the Sustainable Grazing Systems (SGS) whole-farm biophysical model. Animal Production Science 54, 1995–2002.

Fulkerson WJ, Slack A, Hennessey DW, Hough GM (1998) Nutrients in ryegrass (Lolium spp.), white clover (Trifolium repens) and kikuyu (Pennisetum clandestinum) pastures in relation to season and stage of regrowth in a subtropical environment. Australian Journal of Experimental Agriculture 38, 227–240.
Nutrients in ryegrass (Lolium spp.), white clover (Trifolium repens) and kikuyu (Pennisetum clandestinum) pastures in relation to season and stage of regrowth in a subtropical environment.CrossRef | 1:CAS:528:DyaK1cXksVyhuro%3D&md5=c3c788d81771a2b8d5adee977bbfb382CAS |

Fulkerson WJ, Neal JS, Clark CF, Horadagoda A, Nandra KS, Barchia I (2007) Nutritive value of forage species grown in the warm temperate climate of Australia for dairy cows: grasses and legumes. Livestock Science 107, 253–264.
Nutritive value of forage species grown in the warm temperate climate of Australia for dairy cows: grasses and legumes.CrossRef |

Fulkerson B, Griffiths N, Sinclair K, Beale P (2010) ‘Milk production from kikuyu grass based pastures. Primefact 1068.’ (NSW Department of Industry and Investment: Sydney)

Garcia SC, Fulkerson WJ, Brookes SU (2008) Dry matter production, nutritive value and efficiency of nutrient utilization of a complementary forage rotation compared to a grass pasture system. Grass and Forage Science 63, 284–300.
Dry matter production, nutritive value and efficiency of nutrient utilization of a complementary forage rotation compared to a grass pasture system.CrossRef | 1:CAS:528:DC%2BD1cXht1ait73N&md5=d0be3b40d32c41bcce4e8f5ae5d91cf9CAS |

Garcia SC, Islam MR, Clark CEF, Martin PM (2014) Kikuyu-based pasture for dairy production: a review. Crop and Pasture Science 65, 787–797.
Kikuyu-based pasture for dairy production: a review.CrossRef |

Gaughan JB, Bonner S, Loxton I, Mader TL, Lisle A, Lawrence R (2014) Effect of shade on body temperature and performance of feedlot steers. Journal of Animal Science 88, 4056–4067.
Effect of shade on body temperature and performance of feedlot steers.CrossRef |

Gerber PJ, Steinfeld H, Henderson B, Mottet A, Opio C, Dijkstra J, Falcucci A, Tempio G (2013) ‘Tackling climate change through livestock: a global assessment of emissions and mitigation opportunities.’ (Food and Agriculture Organization of the United Nations (FAO): Rome)

Gilmour D, Swann C, Ryan M, Nelson N (2012) Dairy industry farm monitor project annual report 2011/12. Department of Primary Industries, Melbourne.

Harrison MT, McSweeney C, Tomkins NW, Eckard RJ (2015) Improving greenhouse gas emissions intensities of subtropical and tropical beef farming systems using Leucaena leucocephala. Agricultural Systems 136, 138–146.
Improving greenhouse gas emissions intensities of subtropical and tropical beef farming systems using Leucaena leucocephala.CrossRef |

Harrison MT, Cullen BR, Tomkins NW, McSweeney C, Cohn P, Eckard RJ (2016) The concordance between greenhouse gas emissions, livestock production and profitability of extensive beef farming systems. Animal Production Science 56, 370–384.
The concordance between greenhouse gas emissions, livestock production and profitability of extensive beef farming systems.CrossRef |

Hoffman PC, Funk DA (1992) Applied dynamics of dairy replacement growth and management. Journal of Dairy Science 75, 2504–2516.
Applied dynamics of dairy replacement growth and management.CrossRef |

Hough G (1992) ‘Dairy horizons: the challenge for extension. Proceedings of the DRDC extension conference, November 1992’. pp. 176–177. (La Trobe University: Melbourne)

IPCC (2006) ‘2006 IPCC Guidelines for National Greenhouse Gas Inventories.’ Prepared by the National Greenhouse Gas Inventories Programme. (Eds HS Eggleston, L Buendia, K Miwa, T Ngara, K Tanabe) (Institute for Global Environmental Strategies: Hayama, Japan)

Isbell R (2002) ‘The Australian soil classification.’ Revised edn. (CSIRO Publishing: Melbourne)

Jagoe S, Beggs D (2013) ‘Heifers on target: a guide to growing more productive heifers.’ (Dairy Australia: Melbourne)

Jeffrey SJ, Carter JO, Moodie KM, Beswick AR (2001) Using spatial interpolation to construct a comprehensive archive of Australia climate data. Environmental Modelling & Software 16, 309–330.
Using spatial interpolation to construct a comprehensive archive of Australia climate data.CrossRef |

Johnson IR (2013) ‘DairyMod and the SGS pasture model: a mathematical description of the biophysical model structure.’ (IMJ Consultants: Dorrigo, NSW)

Johnson IR, France J, Thornley JHM, Bell MJ, Eckard RJ (2012) A generic model of growth, energy metabolism, and body composition for cattle and sheep. Journal of Animal Science 90, 4741–4751.
A generic model of growth, energy metabolism, and body composition for cattle and sheep.CrossRef | 1:CAS:528:DC%2BC3sXisV2qurc%3D&md5=c01b2c72e73e0424ce81c8ae056d65f1CAS | 22871927PubMed |

Kemp DR (1975) The growth of three tropical pasture grasses on the mid-north coast of New South Wales. Australian Journal of Experimental Agriculture and Animal Husbandry 15, 637–644.
The growth of three tropical pasture grasses on the mid-north coast of New South Wales.CrossRef |

Kempton K, Waterman C (2014) Dairy farm monitor project New South Wales annual report 2012/13. NSW Department of Primary Industries, Orange, NSW.

Le Cozler Y, Lollivier V, Lacasse P, Disenhaus C (2008) Rearing strategy and optimizing first-calving targets in dairy heifers: a review. Animal 2, 1393–1404.
Rearing strategy and optimizing first-calving targets in dairy heifers: a review.CrossRef | 1:STN:280:DC%2BC38vptFWjtg%3D%3D&md5=46dc560f1ba08d7810675773142f7f56CAS | 22443830PubMed |

Lodge G, Johnson I (2007) Impact of climate variability on predicted annual pasture intake of sheep grazing native pastures in northern NSW. In ‘Pasture systems: managing for a variable climate. Proceedings of the 22nd annual conference on the Grassland Society of NSW, Queanbeyan, NSW, July 2007’. (Ed. HL Davies) pp. 112–115. (NSW Grassland Society Inc.: Orange)

Marais JP (2001) Factors affect the nutritive value of kikuyu grass (Pennisetum clandestinum): a review. Tropical Grasslands 35, 65–84.

Marcillac-Embertson NM, Robinson PH, Fadel JG, Mitloehner FM (2009) Effects of shade and sprinklers on performance, behaviour, physiology and the environment of heifers. Journal of Dairy Science 92, 506–517.

Moss RJ (1993) Rearing heifers in the subtropics and tropics: nutrient requirements and supplementation. Tropical Grasslands 27, 238–249.

Powell R, Edwards C, Hegarty RS, McPhee MJ (2011) Impacts of a two degree increase in temperature on pasture growth in the Northern Tablelands of New South Wales. In ‘19th international congress on modelling and simulation (MODSIM2011)’. (Eds F Chan, D Marinova, RS Anderssen) pp. 857–862. (Modelling & Simulation Society of Australia & New Zealand (MSSANZ): Christchurch, New Zealand)

Rawnsley RP, Cullen BR, Turner LR, Donaghy DJ, Freeman M, Christie KM (2009) Potential of deficit irrigation to increase marginal irrigation response of perennial ryegrass (Lolium perenne L.) on Tasmanian dairy farms. Crop and Pasture Science 60, 1156–1164.
Potential of deficit irrigation to increase marginal irrigation response of perennial ryegrass (Lolium perenne L.) on Tasmanian dairy farms.CrossRef |

Reeves M, Fulkerson WJ, Kellaway RC (1996) Forage quality of kikuyu (Pennisetum clandestinum): the effect of time of defoliation and nitrogen fertiliser application and in comparison with perennial ryegrass (Lolium perenne). Australian Journal of Agricultural Research 47, 1349–1359.
Forage quality of kikuyu (Pennisetum clandestinum): the effect of time of defoliation and nitrogen fertiliser application and in comparison with perennial ryegrass (Lolium perenne).CrossRef |

Steinfeld H, Gerber P, Wassenaar T, Castel V, Rosales M, de Haan C (2006) ‘Livestock’s long shadow: environmental issues and options.’ (Food and Agriculture Organization of the United Nations: Rome)



Rent Article (via Deepdyve) Supplementary MaterialSupplementary Material (1.8 MB) Export Citation Cited By (1)