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RESEARCH ARTICLE

Profitability of grazing crop stubbles may be overestimated by using the metabolisable energy intake from the stubble

D. T. Thomas A E , J. Finlayson B , A. D. Moore C and M. J. Robertson D
+ Author Affiliations
- Author Affiliations

A CSIRO Livestock Industries, Private Bag 5, Wembley, WA 6913, Australia.

B School of Agricultural and Resource Economics and Future Farm Industries CRC, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.

C CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2061, Australia.

D CSIRO Sustainable Ecosystems, Private Bag 5, Wembley, WA 6913, Australia.

E Corresponding author. Email: dean.thomas@csiro.au

Animal Production Science 50(7) 699-704 https://doi.org/10.1071/AN09213
Submitted: 17 December 2009  Accepted: 4 May 2010   Published: 30 July 2010

Abstract

Grazing crop stubbles affects soil structure, groundcover, and the productivity of subsequent crops, but the cost of this practice is highly variable and not easily compared against the value of feed provided to livestock. To compare with and without grazing stubbles in terms of whole-farm profit and water-use efficiency we created a mixed enterprise farm model using the Agricultural Production Systems Simulator and GRAZPLAN biophysical simulation submodels, and the Model of Integrated Dryland Agricultural System linear programming model. We hypothesised that grazing crop stubbles would increase farm profit by an amount equivalent to the value of the metabolisable energy (ME) consumed by sheep when they grazed the crop stubbles. Representative mixed farms where sheep were or were not allowed to graze crop stubbles were compared for two locations in the wheatbelt of Western Australia (Cunderdin and Geraldton) at two stocking rates. Across locations and stocking rates, the estimated value of the ME intake from crop stubbles was 2.2 times the increase in farm gross margin when stubble grazing was allowed. Contributing to this difference was that stubble grazing provided a less flexible feed source than supplementary feeding and in the absence of adjustments in stocking rates sheep tended to utilise more of the annual and permanent pastures when stubble grazing was not permitted. Therefore, the value of grazing crop stubbles to the profitability of the farm enterprise was overestimated by the ME value of the intake. Owing to reduced consumption of supplementary feed by livestock, whole-farm water-use efficiency of protein production was increased by 15% when grazing of crop stubbles was permitted. This simulation study shows that the value of grazing crop stubbles cannot be predicted well using energy intake from stubble grazing or reduced supplementary feeding costs.


Acknowledgements

This work was supported by the Grains Research and Development Corporation through the pre-experimental modelling for the Grain & Graze 2 project. We thank Julianne Lilley, James Hunt, Lindsay Bell, John Kirkegaard, Phil Barrett-Lennard and David Masters for their contribution to the design of the farm simulations, and Dean Revell for comments on the manuscript. Dean Thomas was the recipient of a CSIRO J. M. Rendel Fellowship.


References


ABARE (2008) ‘Australian commodity statistics – 2008.’ (Australian Bureau of Agricultural and Resource Economics: Canberra)

Bathgate AD (1989) The effect on farm profit of conserving stubble to prevent wind erosion. Journal of Agriculture, Western Australia 30, 15–17. [Verified 28 June 2010]

Freer M, Moore AD, Donnelly JR (1997) GRAZPLAN: decision support systems for Australian grazing enterprises. 2. The animal biology model for feed intake, production and reproduction and the GrazFeed DSS. Agricultural Systems 54, 77–126.
Crossref | GoogleScholarGoogle Scholar | [Verified 28 June 2010]

Moore AD, Holzworth DP, Herrmann NI, Huth NI, Robertson MJ (2007) The Common Modelling Protocol: a hierarchical framework for simulation of agricultural and environmental systems. Agricultural Systems 95, 37–48.
Crossref | GoogleScholarGoogle Scholar | open url image1

Moore AD, Bell LW, Revell DK (2009) Feed gaps in mixed-farming systems: insights from the Grain & Graze program. Animal Production Science 49, 736–748.
Crossref | GoogleScholarGoogle Scholar | open url image1

Morrison DA, Kingwell RS, Pannell DJ, Ewing MA (1986) A mathematical programming model of a crop-livestock farm system. Agricultural Systems 20, 243–268.
Crossref | GoogleScholarGoogle Scholar | open url image1

Mulholland JG, Coombe JB, Freer M, McManus WR (1976) Evaluation of cereal stubbles for sheep production. Australian Journal of Agricultural Research 27, 881–893.
Crossref | GoogleScholarGoogle Scholar | open url image1

Pannell DJ (1996) Lessons from a decade of whole-farm modelling in Western Australia. Review of Agricultural Economics 18, 373–383.
Crossref | GoogleScholarGoogle Scholar | open url image1

Pannell DJ (1997) ‘Introduction to practical linear programming.’ (Wiley Interscience: New York)

Proffitt APB, Bendotti S, Howell MR, Eastham J (1993) The effect of sheep trampling and grazing on soil physical properties and pasture growth for a red-brown earth. Australian Journal of Agricultural Research 44, 317–331.
Crossref | GoogleScholarGoogle Scholar | open url image1

Proffitt APB, Bendotti S, McGarry D (1995) A comparison between continuous and controlled grazing on a red duplex soil. 1. Effects on soil physical characteristics. Soil & Tillage Research 35, 199–210.
Crossref | GoogleScholarGoogle Scholar | open url image1

Quiroga A, Fernández R, Noellemeyer E (2009) Grazing effect on soil properties in conventional and no-till systems. Soil & Tillage Research 105, 164–170.
Crossref | GoogleScholarGoogle Scholar | open url image1

Radford BJ, Yule DF, Braunack M, Playford C (2008) Effects of grazing sorghum stubble on soil physical properties and subsequent crop performance. American Journal of Agricultural and Biological Science 3, 734–742.
Crossref | GoogleScholarGoogle Scholar | open url image1

Robertson M, Bathgate A, Moore A, Lawes R, Lilley J (2009) Seeking simultaneous improvements in farm profit and natural resource indicators: a modelling analysis. Animal Production Science 49, 826–836.
Crossref | GoogleScholarGoogle Scholar | open url image1

Standing Committee on Agriculture (1990) ‘Feeding standards for Australian livestock. Ruminants.’ (CSIRO Publications: East Melbourne)

Vanhaveren BP (1983) Soil bulk-density as influenced by grazing intensity and soil type on a shortgrass prairie site. Journal of Range Management 36, 586–588.
Crossref | GoogleScholarGoogle Scholar | open url image1