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Compensatory growth in immature sheep: II. Some changes in the physical and chemical composition of sheep half-carcass following feed restriction and realimentation*

Published online by Cambridge University Press:  27 March 2009

K. R. Drew
Affiliation:
Department of Animal Science, Cornell University, Ithaca, New York 14850
J. T. Reid
Affiliation:
Department of Animal Science, Cornell University, Ithaca, New York 14850

Summary

Experimental conditions and design were described in part I. Separable lean and fat were highly correlated with the carcass and whole body components of protein and ether extract. The carcasses of refed sheep at 45 kg empty body weight (EBW) had about 1 kg less fat and more lean than carcasses from sheep of similar weight which had been continuously fed. Restricting feed intake to 70% ad libitum gave carcasses that had more protein than those from sheep fed ad libitum both during continuous growth and after realimentation.

Sheep that had lost 25% EBW to 26 kg and then were refed to 31 kg EBW had 34% less separable carcass fat than sheep which had been continuously fed to EBW of 36 kg and then had lost weight from that level to 31 kg EBW, and the separable fat was higher in water content than during normal growth (an effect shown consistently in realimented sheep).

Severe underfeeding rapidly reduced bone water but bone ether extract continued to accumulate. After a period of refeeding, bone fat was rapidly mobilized and bone water quickly returned to normal. During early weight loss following food intake reduction, there was a larger decrease in carcass water than expected, and most of the discrepancy could be accounted for by the disproportionately large loss of water from bone and separable fat.

It is concluded that during early regrowth there is a marked stimulus of lean tissue growth and depressed fat synthesis. After this initial period, growth rate of carcass tissues is not greatly different from that found in continuously growing sheep although there is some evidence of a small positive rate of protein growth effect following through to 45 kg EBW in the refed animals. The ratio of muscle gain to fat gain from 30 to 40 kg EBW was 2·23 in realimented sheep and 1·08 during normal growth.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1975

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References

REFERENCES

Burton, J. H. (1967). The effects of age and weight on the body composition of sheep. M.S. Thesis, Cornell University, Ithaca, New York.Google Scholar
Burton, J. H. (1970). The efficiency of energy utilisation and changes in adipose tissue during periods of growth, weight reduction and realimentation in sheep. Ph.D. Thesis, Cornell University, Ithaca, New York.Google Scholar
Butterfield, R. M. (1963). Estimation of carcass composition: the anatomical approach. Symposium on Carcass Composition and Appraisal of Meat Animals (ed. Tribe, D. E.), Section 4, 1. Melbourne, Australia: C.S.I.R.O.Google Scholar
Butterfield, R. M. (1966). The effects of nutritional stress and recovery on the body composition of cattle. Research in Veterinary Science 7, 168.CrossRefGoogle ScholarPubMed
Drew, K. R. & Reid, J. T. (1975a). Compensatory growth in immature sheep. I. The effects of weight loss and realimontation on the whole body composition. Journal of Agricultural Science, Cambridge 85, 193204.CrossRefGoogle Scholar
Drew, K. R. & Reid, J. T. (1975b). Compensatory growth in immature sheep. III. Feed utilization in sheep subjected to feed deprivation followed by realimentation. Journal of Agricultural Science, Cambridge 85, 215220.CrossRefGoogle Scholar
Howarth, R. E. & Baldwin, R. L. (1971). Synthesis and accumulation of protein and nucleic acids in rat gastroenomius muscles during normal growth, restricted growth and recovery from restricted growth. Journal of Nutrition 101, 485.CrossRefGoogle ScholarPubMed
Kellaway, R. C. (1973). The effects of plane of nutrition, genotype and sex on growth, body composition and wool production in grazing sheep. Journal of Agricultural Science, Cambridge 80, 17.CrossRefGoogle Scholar
Keenan, D. M., McManus, W. R. & Freer, M. (1969). Changes in the body composition and efficiency of mature sheep during loss and regain of liveweight. Journal of Agricultural Science, Cambridge 72, 139.CrossRefGoogle Scholar
Lohse, C. L., Moss, F. P. & Butterfield, R. M. (1971). Growth patterns of muscles of Merino sheep from birth to 517 days. Animal Production 13, 117.Google Scholar
McManus, W. R., Reid, J. T. & Donaldson, L. E. (1972). Studies of compensatory growth in sheep. Journal of Agricultural Science, Cambridge 79, 1.CrossRefGoogle Scholar
Meyer, J. H. & Clawson, W. J. (1964). Undemutrition and subsequent realimentation in rats and sheep. Journal of Animal Science 23, 214.CrossRefGoogle Scholar
Reid, J. T., Bensadoun, A., Bull, L. S., Burton, J. H., Gleeson, P. A., Han, I. K., Joo, Y. D., Johnson, D. E., McManus, W. R., Paladines, O. L., Stroud, J. W., Tyrell, H. F., Van Niekerk, B. D. H. & Wellington, G. W. (1968). Some peculiarities in the body composition of animals. Body Composition in Animals and Man. National Academy Science Publication, no. 1598, p. 19.Google Scholar
Seebeck, R. M. (1973). The effect of body weight loss on the composition of Brahman cross and Africander cross steers. II. Dissected components of the dressed carcass. Journal of Agricultural Science, Cambridge 80, 411.CrossRefGoogle Scholar
Seebeck, R. M. & Tulloh, N. M. (1968). Developmental growth and body weight loss of cattle. II. Dissected components of the commercially dressed and jointed carcass. Australian Journal of Agricultural Research 19, 477.CrossRefGoogle Scholar
Tulloh, N. M. (1963). The carcass composition of sheep, cattle and pigs as functions of body weight. Symposium on Carcass Composition and Appraisal of Meat Animals (ed. Tribe, D. E.), Section 5, 1. Melbourne, Australia: C.S.I.R.O.Google Scholar
Wilson, P. N. & Osbourn, D. F. (1960). Compensatory growth after undernutrition in mammals and birds. Biological Review 35, 324.CrossRefGoogle ScholarPubMed