Modelling the risk of different joining times and lamb sale policies
S. M. Robertson A B C E , A. F. Southwell B C D and M. A. Friend A B CA School of Animal and Veterinary Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
B Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
C Co-operative Research Centre for Future Farm Industries, UWA, Crawley, WA 6009, Australia.
D School of Agricultural and Wine Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
E Corresponding author. Email: surobertson@csu.edu.au
Animal Production Science 54(10) 1694-1698 https://doi.org/10.1071/AN14119
Submitted: 25 February 2014 Accepted: 18 June 2014 Published: 19 August 2014
Abstract
Month of joining and lamb sale strategy influence both the quantity and so value of lamb produced, and the feed required, so are important management decisions contributing to the profitability of sheep systems. Simulation modelling was used to evaluate the impact on gross margins of three lamb sale strategies for different months of joining and varying stocking rates. A flock of purchased Merino ewes producing crossbred lambs in southern Australia was modelled between 1971 and 2011. April joining produced higher gross margins than November or January only if the number of ewes per hectare was increased to potential carrying capacity. At the optimum stocking rate for each month of joining, three sale policies – a flexible lamb sale policy (where lambs were sold depending on seasonal conditions); selling lambs in December; or selling at 45-kg liveweight, all produced a similar mean gross margin, but the feed resources required were least using the flexible strategy (April-joined mean 195 ± 253 s.d. kg/ha for flexible compared with 219 ± 270 kg/ha if selling December or 1085 ± 459 kg/ha if sold at 45 kg). Mean gross margin differed between sale strategies by up to AU$66/ha if the optimal stocking rate was not used. These results suggest that the most advantageous lamb sale strategy will vary with both month of joining and stocking rate used, and should be considered when optimising sheep management systems.
Additional keywords: management, nutrition, reproduction, sheep.
References
ABARES (2010) ‘Australian commodity statistics 2010.’ (Australian Government: Canberra)ABARES (2011) ‘Agricultural commodity statistics 2011.’ (Australian Government: Canberra)
Casburn G (2010) The profitability of a lamb meat system is greatly influenced by lambing time. Australian Farm Business Management Journal 7, 38–44.
Doole GJ, Bathgate AD, Robertson MJ (2009) Labour scarcity restricts the potential scale of grazed perennial plants in the Western Australian wheatbelt. Animal Production Science 49, 883–893.
| Labour scarcity restricts the potential scale of grazed perennial plants in the Western Australian wheatbelt.Crossref | GoogleScholarGoogle Scholar |
Hopkins DL, Hegarty RS, Farrell TC (2005) Relationship between sire estimated breeding values and the meat and eating quality of meat from their progeny grown on two planes of nutrition. Australian Journal of Experimental Agriculture 45, 525–533.
| Relationship between sire estimated breeding values and the meat and eating quality of meat from their progeny grown on two planes of nutrition.Crossref | GoogleScholarGoogle Scholar |
Kopke E, Young J, Kingwell R (2008) The relative profitability and environmental impacts of different sheep systems in a Mediterranean environment. Agricultural Systems 96, 85–94.
| The relative profitability and environmental impacts of different sheep systems in a Mediterranean environment.Crossref | GoogleScholarGoogle Scholar |
MLA (2014) ‘Meat and Livestock weekly stats, 15 May 2014.’ (MLA)
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.
Robertson SM, Friend MA (2013) Modelling complex sheep systems using AusFarm. In ‘Revitalising grasslands to sustain our communities. Proceedings of the 22nd international grasslands conference, 15–19 September 2013, Sydney, Australia’. (Eds DL Michalk, GD Millar, WB Badgery, KM Broadfoot) pp. 627–628. (NSW Department of Primary Industry)
Robertson SM, Wimalasuriya RK (2004) Limitations to pasture and sheep enterprises and options for improvement in the Victorian Mallee. Australian Journal of Experimental Agriculture 44, 841–849.
| Limitations to pasture and sheep enterprises and options for improvement in the Victorian Mallee.Crossref | GoogleScholarGoogle Scholar |
Salmon L, Donnelly JR, Moore AD, Freer M, Simpson RJ (2004) Evaluation of options for production of large lean lambs in south-eastern Australia. Animal Feed Science and Technology 112, 195–209.
| Evaluation of options for production of large lean lambs in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Warn L, Webb Ware J, Salmon L, Donnelly J, Alcock D (2006) Analysis of the profitability of sheep wool and meat enterprises in southern Australia. Final report for Project 1.2.6. Sheep Co-operative Research Centre.
Young JM, Thompson AN, Kennedy AJ (2010) Bioeconomic modelling to identify the relative importance of a range of critical control points for prime lamb production systems in south-west Victoria. Animal Production Science 50, 748–756.
| Bioeconomic modelling to identify the relative importance of a range of critical control points for prime lamb production systems in south-west Victoria.Crossref | GoogleScholarGoogle Scholar |
