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Maternal nitrogen balance of dairy cows during late gestation

Published online by Cambridge University Press:  20 November 2017

G. Jaurena
Affiliation:
Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth SY23 3EB, UK
J. M. Moorby
Affiliation:
Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth SY23 3EB, UK
W. J. Fisher
Affiliation:
Institute of Grassland and Environmental Research, Trawsgoed Farm, Trawsgoed, Aberystwyth SY23 4LL, UK
D. W. R. Davies
Affiliation:
Institute of Grassland and Environmental Research, Trawsgoed Farm, Trawsgoed, Aberystwyth SY23 4LL, UK
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Extract

Previous results have shown that during late gestation even under conditions of live weight (LW) gain, maternal body protein can be in negative balance due to the highly demanding gravid uterus and udder. It has also been claimed that current feeding standards underpredict dry cow nitrogen (N) requirement. Considering that it is not possible to measure maternal body N status independently of the requirements of the conceptus and the udder, estimation of conceptus and udder N requirements by mathematical models can help to predict maternal N requirement. The aim of this study was to assess cow N requirement during late gestation by predicting maternal N balance through a mathematical model. Previous results related with this study were presented in Jaurena et al, (2001).

Type
Poster Presentations
Copyright
Copyright © The British Society of Animal Science 2002

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References

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