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Validation of intake estimates in grazing beef cattle

Published online by Cambridge University Press:  27 March 2009

K. W. Moir ,
J. P. Ebersohn  and
J. Evans
K. W. Moir
Affiliation:
Queensland Department of Primary Industries, Animal Research Institute, Yeerongpilly, Brisbane 4105, Australia
J. P. Ebersohn
Affiliation:
Queensland Department of Primary Industries, Animal Research Institute, Yeerongpilly, Brisbane 4105, Australia
J. Evans
Affiliation:
Queensland Department of Primary Industries, Animal Research Institute, Yeerongpilly, Brisbane 4105, Australia
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Summary

Growing beef cattle grazed six pasture types (all-grass or grass-legume mixtures) for 4 months on each. Live weight (mean of ten animals) and dietary energy concentration were measured at 2- or 3-weekly intervals. Values for feed intake estimated by back-calculating from feeding standards were on average 2·5% higher (range, 10% less to 12 % higher) than intake values estimated directly from dietary energy concentration and live weight. In contrast to this level of agreement of means, differences between methods within pastures were so large as to suggest the presence of overriding effects on predictors of voluntary intake. It was concluded that until these overriding effects are explained, there are no means of validating measured intakes in grazing cattle, or of accurately predicting the amount of beef produced from pasture.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 99 , Issue 1 , August 1982 , pp. 209 - 213
Copyright
Copyright © Cambridge University Press 1982

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References

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