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Aspects of rumen microbiology central to mechanistic modelling of methane production in cattle

Published online by Cambridge University Press:  26 March 2008

J. L. ELLIS ,
J. DIJKSTRA ,
E. KEBREAB ,
A. BANNINK ,
N. E. ODONGO ,
B. W. McBRIDE  and
J. FRANCE
J. L. ELLIS*
Affiliation:
Centre for Nutrition Modelling, Department of Animal and Poultry Science, University of Guelph, Guelph, ON, N1G 2W1, Canada
J. DIJKSTRA
Affiliation:
Animal Nutrition Group, Wageningen Institute of Animal Sciences, Wageningen University, Marijkeweg 40, 6709 PG, Wageningen, The Netherlands
E. KEBREAB
Affiliation:
Department of Animal Science, University of Manitoba, Winnipeg, MB, R3T 2N2, Canada
A. BANNINK
Affiliation:
Animal Sciences Group, Division Animal Production, Wageningen University and Research Centre, PO Box 65, 8200 AB Lelystad, The Netherlands
N. E. ODONGO
Affiliation:
Agriculture and Agri-Food Canada, Lethbridge Research Centre, Lethbridge, AB, T1J 4B1, Canada
B. W. McBRIDE
Affiliation:
Centre for Nutrition Modelling, Department of Animal and Poultry Science, University of Guelph, Guelph, ON, N1G 2W1, Canada
J. FRANCE
Affiliation:
Centre for Nutrition Modelling, Department of Animal and Poultry Science, University of Guelph, Guelph, ON, N1G 2W1, Canada
*
*To whom all correspondence should be addressed. Email: jellis@uoguelph.ca
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Summary

Methane, in addition to being a significant source of energy loss to the animal that can range from 0·02 to 0·12 of gross energy intake, is one of the major greenhouse gases being targeted for reduction by the Kyoto protocol. Thus, one of the focuses of recent research in animal science has been to develop or improve existing methane prediction models in order to increase overall understanding of the system and to evaluate mitigation strategies for methane reduction. Several dynamic mechanistic models of rumen function have been developed which contain hydrogen gas balance sub-models from which methane production can be predicted. These models predict methane production with varying levels of success and in many cases could benefit from further development. Central to methane prediction is accurate volatile fatty acid prediction, representation of the competition for substrate usage within the rumen, as well as descriptions of protozoal dynamics and pH. Most methane models could also largely benefit from an expanded description of lipid metabolism and hindgut fermentation. The purpose of the current review is to identify key aspects of rumen microbiology that could be incorporated into, or have improved representation within, a model of ruminant digestion and environmental emissions.

Type
Modelling Animal Systems Paper
Information
The Journal of Agricultural Science , Volume 146 , Issue 2: Modelling Animal Systems , April 2008 , pp. 213 - 233
Copyright
Copyright © Cambridge University Press 2008

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References

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