Hostname: page-component-848d4c4894-nmvwc Total loading time: 0 Render date: 2024-06-28T08:20:09.016Z Has data issue: false hasContentIssue false
  • English
  • Français

Changes in body composition of sheep selected for high and low backfat thickness, during periods of ad libitum and maintenance feeding

Published online by Cambridge University Press:  02 September 2010

J. Afonso  and
J. M. Thompson
J. Afonso
Affiliation:
Department of Animal Science, University of New England, Armidale, Australia
J. M. Thompson
Affiliation:
Department of Animal Science, University of New England, Armidale, Australia
Get access

Abstract

Coopworth sheep from the high and low backfat selection lines and from one random-bred line developed at Invermay, New Zealand, were used to examine the interaction between the degree offatness of sheep and a period of maintenance feeding (from 20 to 35 weeks of age), in terms of total fat, carcass lean tissue, bone and viscera weights, relative to the empty body weight measured in computer-aided tomography scans. A similar study was done for weights of subcutaneous, intermuscular and internal (abdominal) fat partitions relative to total fat weight. During two a d libitum feeding periods (front 10 to 20 and from 35 to 43 weeks of age) changes in the same components relative to the ‘whole’ (empty body weight or total fat, depending on the case) were expressed in allometric terms.

Only the allometric growth coefficient for total fat weight was significantly affected by the period of restricted feeding, decreasing after this period. No line or sex effect was observed on any growth coefficient. As a result, there were no changes in differences between treatments over the ad libitum feeding periods, with fat animals and females having significantly higher proportions of fat, while females also had a significantly lower proportion of intermuscular fat.

During maintenance feeding, line and sex differences in dissectible component weights did not change significantly, except in terms of intermuscular fat, with the males showing an increasingly larger proportion than the females.

Keywords

allometrybody compositionbodyfatsheep
Type
Research Article
Information
Animal Science , Volume 63 , Issue 3 , December 1996 , pp. 395 - 406
Copyright
Copyright © British Society of Animal Science 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Afonso, J. J. and Barata, G. 1994. [Estimation of body composition in sheep from data obtained by computerized tomography(CT)]. Revista Portuguesa de Ciencias Veterindrias 89: 176–184.Google Scholar
Aziz, N. N. and Murray, D. M. 1987. The effect of weight stasis on the chemical composition of Merino wethers. In Herbivore nutrition research. Research papers presented to the second international symposium on the nutrition of herbivores. (ed. Rose, M.), an occasional publication of the Australian Society of Animal Production, pp. 155–156.Google Scholar
Blaxter, K. L. and Boyne, A. W. 1982. Fasting an d maintenance metabolism of sheep, journal of Agricultural Science, Cambridge. 99: 611–620.CrossRefGoogle Scholar
Butler-Hogg, B. W. and Johnsson, I. D. 1986. Fat partitioning and tissue distribution in crossbred ewes following different growth paths. Animal Production. 42: 65–72.Google Scholar
Butterfield, R. M. and Thompson, J. M. 1983. Changes in body composition relative t o weight and maturity in large and small strains of Australian Merino rams. 4. Fat depots and bones. Animal Production. 37: 423–431.Google Scholar
Corbett, J. L. 1990. Feeding standards for Australian livestock. Ruminants (ed. Robards, G. E., Radcliffe, J. C.). Australian Agricultural Council, Ruminants Subcommittee, CSIRO.Google Scholar
Donald, G. E., Paull, D. R. and Langlands, J. P. 1984. Liver biopsy as a technique for assessing copper status of sheep. Australian Veterinary Journal 61: 121–123.CrossRefGoogle ScholarPubMed
Fourie, P. D., Kirton, A. H. and Jury, K. E. 1970. Growth and development of sheep. II. Effect of breed and sex on the growth and carcass composition of the Southdown and Romney and their cross. New Zealand journal of Agricultural Research. 13: 753–770.CrossRefGoogle Scholar
Gilmour, A. R. 1989. REG—A generalised linear models program. Miscellaneous bulletin 1. Division of Agricultural Services. New South Wales Department of Agriculture, Sydney, N.S.W., Australia.Google Scholar
Hopkins, A. F. and Congram, I. D. 1985. Australian consumer requirements for beef and lamb. Part 1. Research report no. 19. Livestock and Meat Authority, Queensland.Google Scholar
Kadim, I. T., Purchas, R. W., Rae, A. L. and Barton, R. A. 1988. The distribution and partitioning of fat in Southdown sheep selected for high and low depths of backfat. Proceedings of the 34th international congress of meat science and technology (part A), pp. 65–67.Google Scholar
Keenan, D. M., McManus, W. R. and Freer, M. 1969. Changes in th e body composition and efficiency of mature sheep during loss and regain of live weight. Journal of Agricultural Science, Cambridge. 72: 139–147.CrossRefGoogle Scholar
Little, D. A. and Sandland, R. L. 1975. Studies on the distribution of the bod y fat in sheep during continuous growth, and following nutritional restriction and rehabilitation. Australian Journal of Agricultural Research. 26: 363–374.CrossRefGoogle Scholar
McEwan, J. C., Fennessy, P. F., Bain, W. E. and Greer, G. J. 1990a. Selection for leanness in sheep. Proceedings of the fifth Asian-Australasian Association of Animal Production Societies (AAAP) animal science congress, p. 252.Google Scholar
McEwan, J. C., Fennessy, P. F., Greer, G. J., Bain, W. E. and Bruce, G. D. 1990b. Effects of selection for ultrasonic backfat depth on carcass growth and composition in sheep. Proceedings of the Australian Association of Animal Breeding and Genetics 8: 323–326.Google Scholar
McLeod, M. G. and Geraert, P. A. 1988. Energy metabolism in genetically fat and lean birds and mammals. In Leanness in domestic birds (ed. Leclercq, B., Whitehead, C. C.), pp. 109–120. Butterworths, London.CrossRefGoogle Scholar
McManus, W. R., Reid, J. T. and Donaldson, L. E. 1972. Studies of compensatory growth in sheep. Journal of Agricultural Science, Cambridge. 79: 1–12.CrossRefGoogle Scholar
Murray, D. M. and Slezacek, O. 1988a. The effect of weight stasis on the dissected carcass composition of crossbred sheep. Australian Journal of Agricultural Research. 39: 645–651.CrossRefGoogle Scholar
Murray, D. M. and Slezacek, O. 1988b. The effect of weight stasis on the non-carcass components of crossbred sheep. Australian journal ofAgricultural Research 39: 653–658.CrossRefGoogle Scholar
Murray, D. M., Tulloh, N. M. and Winter, W. H. 1974. Effects of three different growth rates on empt y body weight, carcass weight and dissected carcass composition of cattle. Journal of Agricultural Science, Cambridge. 82: 535–547.CrossRefGoogle Scholar
Notter, D. R., Ferrel, C. L. and Field, R. A. 1983. Effects of breed and intake level on allometric growth patterns in ram lambs, journal of Animal Science. 56: 380–395.CrossRefGoogle Scholar
Searle, T. W. and Graham, N. M. 1975. Studies of weane r sheep during and after a period of weight stasis. II. Body composition. Australian Journal of Agricultural Research. 26: 355–361.CrossRefGoogle Scholar
Stamataris, C., Kyriazakis, I. and Emmans, G. C. 1991. The performance and body composition of young pigs following a period of growth retardation by food restriction. Animal Production. 53: 373–381.Google Scholar
Thompson, J. M. 1990. Correlated responses to selection for growth and leanness in sheep. Proceedings of the fourth world congress on genetics and applied livestock production. 16: 266–275.Google Scholar
Thompson, J. M., Butterfield, R. M. and Perry, D. 1985. Food intake, growth and body composition in Australian Merino sheep selected for high and low weaning weight. 2. Chemical an d dissectible body composition. Animal Production. 40: 71–84.Google Scholar
Thompson, J. M., Butterfield, R. M. and Perry, D. 1987. Food intake, growth and body composition in Australian Merino sheep selected for high and low weaning weight. 4. Partitioning of dissected and chemical fat in the body. Animal Production 45: 49–60.Google Scholar
Thompson, J. M. and Kinghorn, B. 1992. CATMAN—A program to measure CAT-scans for predictio n of body components in live animals. Proceedings of the Australian Asociation of Animal Breeding and Genetics 10: 5.Google Scholar
Turner, H. G. and Taylor, St C. S. 1983. Dynamic factors in models of energy utilization with particular reference to maintenance requirement of cattle. World Review of Nutrition and Dietetics. 42: 135–190.CrossRefGoogle ScholarPubMed
Webster, A. J. F. 1981. The energetic efficiency of metabolism. Proceedings of the Nutrition Society. 40: 121–128.CrossRefGoogle ScholarPubMed
Winter, W. H. 1971. A study of weight loss and compensatory gain in sheep. Ph.D. thesis, University of Melbourne.Google Scholar