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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

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