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A non-linear compartmental model to describe forage degradation kinetics during incubation in polyester bads in the rumen

Published online by Cambridge University Press:  09 March 2007

M.S. Dhanoa
Affiliation:
Institute of Grassiand and Environmental Research, Plas Gogerddan, Aberystwyth, Dyfed SY23 3EB
J. France
Affiliation:
Institute of Grassland and Envirounental Research, North Wyke Research Station, Okehampton, Devon EX20 2SB
R. C. Siddons
Affiliation:
Formerly Institute of Grassland and Environmental Research, Hurley, Maidenhead, Berkshire SL6 5LR
S. Lopez
Affiliation:
Department of Animal Production, University of Leon, 24007 Leon, Spain
J.G. Buchanan-Smith
Affiliation:
Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario NIG 2WI, Canada
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Abstract

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A new model for describing forage degradation kinetics during incubation in the rumen using polyester bags is presented. Attention is given to dealing with the problem of deviations from exponential behaviour in the early stages of degradation by devising a function capable of representing exponential or sigmoidal trends. This is achieved by allowing part of the fractional degradation rate to vary with time of incubation, thus enabling responses other than those expected under simple first-order kinetics to be described. Seven sets of data consisting of 620 curves were analysed to study the performance of the new model compared with a commonly used exponential model. The proportion of significantly better fits varied from set to set. The new model deals successfully with sigmoidal behaviour and, thus, provides a means of analysing the degradation profiles of low-quality

Type
Model for forage degradation kinetics
Copyright
Copyright © The Nutrition Society 1995

References

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