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An integration of mathematical models for feeding and lactation with reproductive performance of the dairy cow

Published online by Cambridge University Press:  02 September 2010

E. A. Goodall  and
C. H. McMurray
E. A. Goodall
Affiliation:
Department of Agriculture for Northern Ireland
C. H. McMurray
Affiliation:
Department of Agriculture for Northern Ireland
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Abstract

A mathematical model based on the energy requirements of the dairy cow and the lactation model of Wood was constructed to determine the effect on net returns over concentrates of different calving intervals for different weeks of the year under different feeding management conditions. The model was computerized, and this enabled an investigation of the effect on net returns of varying silage metabolizable energy levels and different nutritional management systems. The importance of the modelling approach in examining a range of interacting factors simultaneously is highlighted. To illustrate this approach, results are presented here with 1981 prices for milk, concentrates and calves kept constant over a period of 4 years and also, to validate this approach, using actual prices paid over the period 1976 to 1981.

Type
Research Article
Information
Animal Production , Volume 38 , Issue 3 , June 1984 , pp. 341 - 349
Copyright
Copyright © British Society of Animal Science 1984

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References

REFERENCES

Bines, J. A. 1976. Factors influencing voluntary food intake in cattle. In Principles of Cattle Production (ed. Swan, H. and Broster, W. H.), pp. 287–305. Butterworth, London.Google Scholar
Castle, M. E. 1982. eeding high-quality silage. In Silage for Milk Production, Tech. Bull. 2 (ed. Rook, J. A. F. and Thomas, P. C.), pp. 127–150. National Institute for Research in Dairying, Reading.Google Scholar
Department of Agriculture for Northern Ireland. 1975–1981. Statistical Review of Northern Ireland. Agriculture. Her Majesty's Stationery Office, London.Google Scholar
James, A. D. and Esslemont, R. J. 1979. The economics of calving intervals. Anim. Prod. 29: 157–162.Google Scholar
McBratney, J. and Laidlaw, A. S. 1974. The suitability of various grasses, cutting intervals and nitrogen levels for conservation systems as judged by dry matter production. 47th A. Rep. agric. Res. Inst.N. Ire., 1973/74, pp. 21–26.Google Scholar
Milk Marketing Board of Northern Ireland. 1980–1981. A. Rep., 1973–1980 and 1981.Google Scholar
Ministry of Agriculture, Fisheries and Food, Department of Agriculture and Fisheries for Scotland and Department of Agriculture for Northern Ireland. 1975. Energy allowances an d feeding systems for ruminants. Tech. Bull. 33. Her Majesty's Stationery Office, London.Google Scholar
Steen, R. W. J. and Gordon, F. J. 1980. The effect of level and system of concentrate allocation to January/ February calving cows on total lactation performance. Anim. Prod. 30: 39–51.Google Scholar
Unsworth, E. F. 1981. The composition and quality of grass silages made in Northern Ireland—an analysis of seven years' results (1973–1979). Rec. Agric. Res. (N.Ir.) 29: 9–97.Google Scholar
Wood, P. D. P. 1967. Algebraic model of the lactation curve in cattle. Nature, Lond. 216: 164–165.CrossRefGoogle Scholar
Wood, P. D. P. 1969. Factors affecting the shape of the lactation curve in cattle. Anim. Prod. 11: 307–316.Google Scholar
Wood, P. D. P. 1979. A simple model of lactation curves for milk yield, food requirement and body weight. Anim. Prod. 28: 55–63.Google Scholar
Wood, P. D. P. 1980. Breed variations in the shape of the lactation curve of cattle and their implications for efficiency. Anim. Prod. 31: 133–141.Google Scholar