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The use of X-ray computer tomography for measuring the muscularity of live sheep

Published online by Cambridge University Press:  18 August 2016

H. E. Jones ,
R. M. Lewis ,
M. J. Young  and
B. T. Wolf
H. E. Jones
Affiliation:
Animal Biology Division, Scottish Agricultural College, King’s Buildings, Edinburgh EH9 3JG, UK
R. M. Lewis
Affiliation:
Animal Biology Division, Scottish Agricultural College, King’s Buildings, Edinburgh EH9 3JG, UK Department of Animal and Poultry Sciences (0306), Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
M. J. Young
Affiliation:
Animal Biology Division, Scottish Agricultural College, King’s Buildings, Edinburgh EH9 3JG, UK Sheep Improvement Limited, PO Box 66, Lincoln University, Canterbury 8150, New Zealand
B. T. Wolf
Affiliation:
Institute of Rural Studies, University of Wales Aberystwyth, Llanbadarn Campus, Aberystwyth SY23 3AL, UK
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Abstract

Potential measures of muscularity derived from X-ray computer tomography (CT) were assessed using data for 160 sheep (50 Suffolk males, 50 Suffolk females, 40 Texel males and 20 Charollais males). One-fifth of the lambs within each breed and sex were slaughtered at each of 14, 18 or 22 weeks of age and two-fifths slaughtered at 26 weeks. All lambs were CT scanned prior to slaughter with longitudinal and cross-sectional scans taken at three positions along the body [5th lumbar vertebra (LV5), mid-shaft of the femur (FEM) and ischium (ISC)]. After slaughter, linear measurements of side length (SL) and M. longissimus thoracis et lumborum (LTL) width (A) and depth (B) (12/ 13th thoracic vertebra) were taken on the left side of the carcass. The side was dissected and femur length (FL), the weight of three muscles surrounding the femur (M3) and the total muscle weight in the side (TM) were recorded. Five muscularity measures were calculated for the carcass. Two for the LTL muscle (A/SL, B/SL), one for the hind leg (√M3/FL3) and one for the whole carcass (√TM/SL3).

Correlations between spine length measured on the CT longitudinal scans and side length measured on the carcass were high (> 0·62), while correlations between measurements of LTL width and depth on the carcass with those on the LV5 scan were moderate (> 0·41). CT measures of muscularity were derived using linear measurements taken on CT scans together with a prediction of total muscle weight using CT tissue areas. Correlations between CT measures and dissection measures of LTL and whole carcass muscularity were moderate to high (0·33–0·54). Correlations between the dissection measure and four CT measures of hind leg muscularity were higher (0·48-0·60). These results clearly show that good in vivo measures of muscularity can be obtained for sheep by using measurements that can be taken on CT scans. This will be a useful tool for selection programmes aiming to improve sheep carcass shape, particularly those already using CT scanning to increase rates of genetic improvement in lean tissue growth.

Keywords

computed tomographylive estimationmusclessheep.

Information

Type
Research Article
Information
Animal Science , Volume 75 , Issue 3 , December 2002 , pp. 387 - 399
Copyright
Copyright © British Society of Animal Science 2002

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References

Abdullah, A. Y., Purchas, R. W., Davies, A. S. and Kirton, A. H. 1993. Relationships between objective and subjective measurements of carcass muscularity. Proceedings of the New Zealand Society of Animal Production 53: 397–402.Google Scholar
Binnie, D. B., Farmer, R. J. and Clarke, J. N. 1995. Ultrasonic scanning of lamb carcasses for non-destructive carcass quality measurements. Proceedings of the New Zealand Society of Animal Production 55: 111–113.Google Scholar
Boer, H. de, Dumont, B. L., Pomeroy, R. W. and Weniger, J. H. 1974. Manual on EAAP reference methods for the assessment of carcass characteristics in cattle. Livestock Production Science 1: 151–164.Google Scholar
Clarke, R. D., Kirton, A. H., Bartle, C. M. and Dobbie, P. M. 1999. Application of dual-energy X-ray absorptiometry for ovine carcass evaluation. Proceedings of the New Zealand Society of Animal Production 59: 272–274.Google Scholar
Cuthbertson, A., Harrington, G. and Smith, R. J. 1972. Tissue separation-to asses beef and lamb variation. In Symposium on aspects of carcass evaluation. Proceedings of the British Society of Animal Production, pp. 113–122.Google Scholar
Davies, A. S., Garden, K. L., Young, M. J. and Reid, C. S. W. 1987. An atlas of X-ray tomographical anatomy of the sheep. Science Information Publishing Centre, DSIR, bulletin no. 243, Wellington, New Zealand.Google Scholar
Davies, G. H. and Fennessy, P. F. 1996. The organisation of the sheep industry in New Zealand. Proceedings of an international symposium on the sheep industry, October 11-12, Sherbrooke, Quebec, pp. 37–46.Google Scholar
Edwards, J. W., Cannell, R. C., Garrett, R. P., Savell, J. W., Cross, H. R. and Longnecker, M. T. 1989. Using ultrasound, linear measurements and live fat thickness estimates to determine the carcass composition of market lambs. Journal of Animal Science 67: 3322–3330.Google Scholar
Fortin, A. and Shrestha, J. N. B. 1986. In vivo estimation of carcass meat by ultrasound in ram lambs slaughtered at an average live weight of 37 kg. Animal Production 43: 469–475.Google Scholar
Genstat., 1998. Genstat 5 release 4·1 (PC/Windows NT). Lawes Agricultural Trust, Rothamsted Experimental Station, Harpenden.Google Scholar
Hopkins, D. L. 1996. The relationship between muscularity, muscle: bone ratio and cut dimensions in male and female lamb carcasses and the measurement of muscularity using image analysis. Meat Science 44: 307–317.Google Scholar
Hopkins, D. L., Pirlot, K. L., Roberts, A. H. K. and Beattie S. 1993. Changes in fat depth and muscle dimensions in growing lambs as measured by real-time ultrasound. Australian Journal of Experimental Agriculture 33: 707–712.Google Scholar
Houghton, P. L. and Turlington, L. M. 1992. Application of ultrasound for feeding and finishing animals: a review. Journal of Animal Science 70: 930–9411 Google Scholar
Jones, H. E., Lewis, R. M., Young, M. J., Wolf, B. T. and Warkup, C. C. 2002. Changes in muscularity with growth and its relationship with other carcass traits in three terminal sire breeds of sheep. Animal Science 74: 265–275.Google Scholar
Jopson, N. B., McEwan, J. C., Dodds, K. G. and Young, M. J. 1995. Economic benefits of including computer tomography measurements in sheep breeding programmes. Proceedings of the Australian Association of Animal Breeding and Genetics 11: 194–197.Google Scholar
Jopson, N. B., McEwan, J. C., Fennessy, P. F., Dodds, K. G., Nicoll, G. B. and Wade, C. M. 1997. Economic benefits of including computer tomography measurements in a large terminal sire breeding programme. Proceedings of the Association for the Advancement of Animals Breeding and Genetics 12: 72–76.Google Scholar
Kirton, A. H., Woods, E.G. and Dunganzich, D. M. 1983. Comparison of well and poorly muscled lamb carcasses as selected by experienced meat industry personnel. Proceedings of the New Zealand Society of Animal Production 43: 111–113.Google Scholar
Lawrie, R. A. 1991 Meat science, fifth edition. Pergamon Press plc, Oxford.Google Scholar
McEwan, J. C., Clarke, J. N., Knowler, M. A. and Wheeler, M. 1989. Ultrasonic fat depths in Romney lambs and hoggets from lines selected for different production traits. Proceedings of the New Zealand Society of Animal Production 49: 113–119.Google Scholar
Mitchell, A. D., Scholz, A. M. and Conway, J. M. 1998a. Body composition analysis of small pigs by dual-energy X-ray absorptiometry. Journal of Animal Science 76: 2392–2398.Google Scholar
Mitchell, A. D., Scholz, A. M., Pursel, V. G. and Evock-Clover, C. M. 1998b. Composition analysis of pork carcasses by dual-energy X-ray absorptiometry. Journal of Animal Science 76: 2104–2114.Google Scholar
Pálsson, H. 1939. Meat qualities in the sheep with particular reference to Scottish breeds and crosses. 1. Journal of Agricultural Science, Cambridge 29: 544–626.Google Scholar
Purchas, R. W., Davies, A. S. and Abdullah, A. Y. 1991. An objective measure of muscularity: changes with animal growth and differences between genetic lines of Southdown sheep. Meat Science 30: 81–94.Google Scholar
Sehested, E. 1984. Computerised tomography in sheep. In In vivo measurement of body composition in meat animals (ed. Lister, D.), pp. 67–74. Elsevier, London.Google Scholar
Smith, G. C., Dutson, T. R., Hostetler, R. L. and Carpenter, Z. L. 1976. Fatness, rate of chilling and tenderness of lamb. Journal of Food Science 41: 748–756.Google Scholar
Standal, N. 1984. Establishment of a CT facility for farm animals. In In vivo measurement of body composition in meat animals (ed. Lister, D.), pp. 43–51. Elsevier, London.Google Scholar
Standford, K., Jones, S. D. M. and Price, M. A. 1998. Methods of predicting lamb carcass composition: a review. Small Ruminant Research 29: 241–254.Google Scholar
Tallis, G. M., Turner, H. N. and Brown, G. H. 1964. The relationship between live measurements and edible meat in Merino wethers. Australian Journal of Agricultural Research 15: 446–452.Google Scholar
Taneja, G. C. 1955. Mutton qualities in Australian Merino sheep. Australian Journal of Agricultural Research 6: 882–890.Google Scholar
Waldron, D. F., Clarke, J. N., Rae, A. L. and Woods, E.G. 1992. Expected responses in carcass composition to selection for muscularity in sheep. Proceedings of the New Zealand Society of Animal Production 52: 29–31.Google Scholar
Ward, B. G., Purchas, R. W. and Abdullah, A. Y. 1992. The value of ultrasound in assessing the leg muscling of lambs. Proceedings of the New Zealand Society of Animal Production 52: 33–36.Google Scholar
Wiener, G. and Hayter, S. 1974. Body size and conformation in sheep from birth to maturity as affected by breed, crossbreeding, maternal and other factors. Animal Production 19: 47–65.Google Scholar
Wolf, B. T., Jones, D. A. and Owen, M. G. 2001. Carcass composition, conformation and muscularity in Texel lambs of different breeding history, sex and leg shape score. Animal Science 72: 465–475.Google Scholar
Young, M. J., Garden, K. L. and Knopp, T. C. 1987. Computer aided tomography – comprehensive body compositional data from live animals. Proceedings of the New Zealand Society of Animal Production 47: 69–71.Google Scholar
Young, M. J., Lewis, R. M., McLean, K. A., Robson, N. A. A., Fraser, J., Fitzsimons, J., Donbavand, J. and Simm, G. 1999. Prediction of carcass composition in meat breeds of sheep using computer tomography. Proceedings of the British Society of Animal Science, 1999, p. 43.Google Scholar
Young, M. J., Nsoso, S. J., Logan, C. M. and Beatson, P. R. 1996. Prediction of carcass tissue weight in vivo using live weight, ultrasound or X-ray CT measurements. Proceedings of the New Zealand Society of Animal Production 56: 205–211.Google Scholar
Young, M. J., Simm, G. and Glasbey, C. A. 2001. Computerised tomography for carcass analysis. Proceedings of the British Society of Animal Science, 2001, pp. 250–254.Google Scholar
Zar, J. H. 1996. Biostatistical analysis. Prentice-Hall International Inc., Simon and Schuster, Upper Saddle River, NJ.Google Scholar