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Predicting changes in food energy requirements due to genetic changes in growth and body composition of growing ruminants

Published online by Cambridge University Press:  02 September 2010

P. Amer  and
G. C. Emmans
P. Amer
Affiliation:
Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG
G. C. Emmans
Affiliation:
Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG
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Abstract

Incorporation of food intake into breeding objectives for ruminants is often difficult because the relevant genetic parameters are unavailable. A non-statistical approach to estimating the genetic relationships between food costs and genetic changes in growth and body composition traits was therefore developed.

Equations which predict additional food requirements associated with genetic changes in growth and body composition traits are derived from an interspecies growth model. In the growth model, a genotype is mainly described according to its expected mature weights of protein, lipid and a composition trait of interest in the empty body under non-limiting conditions. Other model parameters describe the expected growth of the animal in a specific environment.

An example is shown for beef cattle in the United Kingdom, where increases in carcass weight by 1 kg and carcass subcutaneous fat proportion by 0·01 result in increases in food costs by £0·97 and £7·34 respectively for a production system where animals are given an intensive silage/concentrate diet, are slaughtered at 305 kg and have a commercial fat grade 4L. A strong dependence of the results on the type of production system, especially the degree of maturity in protein at slaughter, is demonstrated.

The model is easily adapted to other breeds and ruminant species. The approach is recommended for incorporating food intake into breeding objectives for ruminants in situations where reliable estimates of the necessary genetic parameters for a more conventional specification of the breeding objective are unavailable.

Keywords

breeding programmesfood intakeruminants
Type
Research Article
Information
Animal Science , Volume 66 , Issue 1 , February 1998 , pp. 143 - 153
Copyright
Copyright © British Society of Animal Science 1998

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References

Allen, D. M. and Steane, D. E. 1985. Beef selection indices. British Cattle Breeders' Club digest no. 40, pp. 63–70.Google Scholar
Bekman, H. and Arendonk, J. A. M. van. 1993. Derivation of economic values for veal, beef and milk production traits using profit equations. Livestock Production Science 34: 35–56.CrossRefGoogle Scholar
Emmans, G. C. 1988. Genetic components of potential and actual growth. In Animal breeding opportunities. British Society of Animal Production occasional publication no. 12, 153–181.Google Scholar
Emmans, G. C. 1994. Effective energy: a concept of energy utilisation applied across species British Journal of Nutrition 71: 801–821.CrossRefGoogle ScholarPubMed
Emmans, G. C. 1997. A method to predict the food intake of domestic animals over time Journal of Theoretical Biology 186: 189–199.CrossRefGoogle Scholar
Gompertz, B. 1825. On the nature of the function expressive of the law of human mortality and on a new method of determining the value of life contingencies. Philosophical Transactions of the Royal Society of London, pp. 513–585.Google Scholar
Hazel, L. N. 1943. The genetic basis for constructing selection indexes Genetics 28: 476–490.CrossRefGoogle ScholarPubMed
James, J. W. 1981. Index selection for simultaneous improvement of several characters. In Well-being of mankind and genetics (ed. Belyaev, D. K.). Proceedings of the 14th international congress of genetics, vol. 1, book 2, pp. 221–229MIR Moscow, USSR.Google Scholar
Jansen, J., Korver, S., Dommerholt, J., Meijering, A. and Oldenbroek, J. K. 1984. A selection index for beef production capacity of performance-tested young bulls in A.I. in Dutch dual-purpose breeds. Livestock Production Science 11: 381–390.CrossRefGoogle Scholar
Kempster, A. J., Cook, G. L. and Grantley-Smith, M. 1986. National estimates of the body composition of British cattle, sheep and pigs with special references to trends in fatness. A review. Meat Science 17: 107–138.CrossRefGoogle ScholarPubMed
Korver, S., Tess, M. W. and Johnson, T. 1988. A model of growth and growth composition for beef bulls and bulls of different breeds Agricultural Systems 27: 279–294.CrossRefGoogle Scholar
MacNeil, M. N. and Newman, S. 1994. Selection indices for Canadian beef production using specialised sire and dam lines Canadian Journal ofAnimal Science 74: 419–424.CrossRefGoogle Scholar
Newman, S., Morris, C. A., Baker, R. L. and Nicoll, G. B. 1992. Genetic improvement of beef cattle in New Zealand: breeding objectives Livestock Production Science 32: 111–130.CrossRefGoogle Scholar
Ponzoni, R. W. 1986. A profit equation for the definition of the breeding objective of Australian Merino sheep Journal ofAnimal Breeding and Genetics 103: 342–357.CrossRefGoogle Scholar
Schneeberger, M., Barwick, S. A., Crow, G. H. and Hammond, K. 1992. Economic indices using breeding values predicted by BLUP Journal of Animal Breeding Genetics 109: 180–187.CrossRefGoogle Scholar
Scottish Agricultural College. 1994. Farm management handbook 1994/95. Scottish Agricultural College, EdinburghGoogle Scholar
Simm, G., Smith, C. and Prescott, J. H. D. 1986. Selection indices to improve the efficiency of lean meat production in cattle Animal Production 42: 183–193.Google Scholar
Simm, G., Young, M. J. and Beatson, P. R. 1987. An economic selection index for lean meat production in New Zealand sheep Animal Production 45: 465–475.Google Scholar
Taylor, St C. S. 1980. Genetic size scaling rules in animal growth Animal Production 30: 161–165.Google Scholar
Tess, M. W., Bennett, G. L. and Dickerson, G. E. 1983a. Simulation of genetic changes in life cycle efficiency of pork production. 1. A bioeconomic model. Journal of Animal Science 56: 336–353.CrossRefGoogle Scholar
Tess, M. W., Bennett, G. L. and Dickerson, G. E. 1983b. Simulation of genetic changes in life cycle efficiency of pork production. 3. Effects of management systems and feed prices on importance of genetic components. Journal of Animal Science 56: 369–379.CrossRefGoogle Scholar