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Food, fibre and pharmaceuticals from animals
RESEARCH ARTICLE

A new method for calculating the volume of primary tissue types in live sheep using computed tomography scanning

C. L. Alston A C , K. L. Mengersen A and G. E. Gardner B
+ Author Affiliations
- Author Affiliations

A School of Mathematical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Qld 4001, Australia.

B School of Veterinary and Biomedical Sciences, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia.

C Corresponding author. Email: c.alston@qut.edu.au

Animal Production Science 49(11) 1035-1042 https://doi.org/10.1071/AN09038
Submitted: 6 March 2009  Accepted: 18 May 2009   Published: 14 October 2009

Abstract

Interest in the use of computed tomography (CT) scanning in animal experimentation has increased markedly over the last decade due to the benefits of studying tissue in live subjects over time. In these experiments, the non-carcass components of the scan are removed from the collected data, allowing scientists to study the carcass of a live animal without the need to slaughter the individual. However, there is not yet a consensus regarding the most appropriate manner in which to convert the CT numbers into a meaningful estimate of area, volume or proportion of tissue present in a carcass at the time of scanning. In this paper we use a Bayesian mixture model to estimate the area of each of three tissue types of interest, fat, muscle and bone present in individual CT scan slices. We then use the Cavalieri principle to estimate the volume and proportion of the carcass attributable to each of these tissues. The approach is validated by analysis of experimental sheep carcasses.

Additional keywords: Bayesian mixture model, Cavalieri method, trapezoidal rule.


Acknowledgements

The authors would like to thank Dr Kelly Pearce for providing the chemical composition values and Ms Neroli Smith for her involvement with collating and editing CT images. We also acknowledge Meat and Livestock Australia for their original funding of the project that has made this data available.


References


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