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Update of the Dutch protein evaluation system for ruminants: the DVE/OEB2010 system

Published online by Cambridge University Press:  19 November 2010

G. VAN DUINKERKEN ,
M. C. BLOK ,
A. BANNINK ,
J. W. CONE ,
J. DIJKSTRA ,
A. M. VAN VUUREN  and
S. TAMMINGA
G. VAN DUINKERKEN*
Affiliation:
Wageningen UR Livestock Research, Edelhertweg 15, 8219 PH Lelystad, The Netherlands
M. C. BLOK
Affiliation:
Product Board Animal Feed, Stadhoudersplantsoen 12, 2517 JL The Hague, The Netherlands
A. BANNINK
Affiliation:
Wageningen UR Livestock Research, Edelhertweg 15, 8219 PH Lelystad, The Netherlands
J. W. CONE
Affiliation:
Animal Nutrition Group, Wageningen University, Marijkeweg 40, 6709 PG Wageningen, The Netherlands
J. DIJKSTRA
Affiliation:
Animal Nutrition Group, Wageningen University, Marijkeweg 40, 6709 PG Wageningen, The Netherlands
A. M. VAN VUUREN
Affiliation:
Wageningen UR Livestock Research, Edelhertweg 15, 8219 PH Lelystad, The Netherlands
S. TAMMINGA
Affiliation:
Animal Nutrition Group, Wageningen University, Marijkeweg 40, 6709 PG Wageningen, The Netherlands
*
*To whom all correspondence should be addressed. Email: gert.vanduinkerken@wur.nl
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Summary

In the current Dutch protein evaluation system (the DVE/OEB1991 system), two characteristics are calculated for each feed: true protein digested in the intestine (DVE) and the rumen degradable protein balance (OEB). Of these, DVE represents the protein value of a feed, while OEB is the difference between the potential microbial protein synthesis (MPS) on the basis of available rumen degradable protein and that on the basis of available rumen degradable energy. DVE can be separated into three components: (i) feed crude protein undegraded in the rumen but digested in the small intestine, (ii) microbial true protein synthesized in the rumen and digested in the small intestine, and (iii) endogenous protein lost in the digestive processes.

Based on new research findings, the DVE/OEB1991 system has recently been updated to the DVE/OEB2010 system. More detail and differentiation is included concerning the representation of chemical components in feed, the rumen degradation characteristics of these components, the efficiency of MPS and the fractional passage rates. For each chemical component, the soluble, washout, potentially degradable and truly non-degradable fractions are defined with separate fractional degradation rates. Similarly, fractional passage rates for each of these fractions were identified and partly expressed as a function of fractional degradation rate. Efficiency of MPS is related to the various fractions of the chemical components and their associated fractional passage rates. Only minor changes were made with respect to the amount of DVE required for maintenance and production purposes of the animal. Differences from other current protein evaluation systems, viz. the Cornell Net Carbohydrate and Protein system and the Feed into Milk system, are discussed.

Type
Modelling Animal Systems
Information
The Journal of Agricultural Science , Volume 149 , Issue 3 , June 2011 , pp. 351 - 367
Copyright
Copyright © Cambridge University Press 2010

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