ORIGINAL PAPER
Effect of variation in the proportion of solid- and
liquid-associated rumen bacteria in duodenal
contents on the estimation of duodenal bacterial
nitrogen flow
1,
1 1 | Laboratory for Animal Nutrition and Animal Product Quality, Ghent University,
Proefhoevestraat 10, 9090 Melle, Belgium |
2 | Institute of Grassland and Environmental Research,
Plas Gogerddan, Aberystwyth, Ceredigion SY23 3EB, UK |
3 | Current address: Agriculture and Life Sciences Division, Lincoln University, Canterbury, New Zealand |
CORRESPONDING AUTHOR
V. Fievez
Laboratory for Animal Nutrition and Animal Product Quality, Ghent University, Proefhoevestraat 10, 9090 Melle, Belgium
Laboratory for Animal Nutrition and Animal Product Quality, Ghent University, Proefhoevestraat 10, 9090 Melle, Belgium
Publication date: 2007-02-02
J. Anim. Feed Sci. 2007;16(1):37–42
KEYWORDS
bacterial Nsolid associated bacterialiquid associated bacteriarumenodd- and branched-chain fatty acids
ABSTRACT
The aim of this research was to examine to what extent variation in the relative proportions of
solid- (SAB) and liquid-associated rumen bacteria (LAB) in duodenal bacteria have an impact on the
estimation of duodenal flow of bacterial N. For this, four dairy cows were fed diets varying in forage:
concentrate ratio (80:20, 65:35, 50:50 and 35:65). SAB and LAB were separated from rumen contents
four h after the morning feeding. Adenine, cytosine and odd and branched-chain fatty acids were
determined both in SAB and LAB and used to estimate bacterial N flow. Bacterial N flows were also
calculated using a SAB:LAB ratio in duodenal bacteria, as estimated from the odd and branched-chain
fatty acid pattern. Compared with calculations based on the estimated SAB:LAB ratio, estimations
based on SAB or LAB only as a bacterial reference on average over- and underestimated bacterial
N flow by 37 and 55 g N/d, respectively (P<0.05) when cytosine or adenine were used as bacterial
marker. In contrast, due to the small differences in the OBCFA:N ratio between SAB and LAB, these
differences were less than 15 g/d when OBCFA were used as bacterial marker. The results suggest that,
depending on the marker used, changes in the proportions of SAB and LAB can have a substantial
impact on estimated duodenal flow of bacterial N.
CITATIONS (4):
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Relationship between milk odd and branched-chain fatty acids and urinary purine derivatives in dairy cows supplemented with quebracho tannins—A study to test milk fatty acids as predictors of rumen microbial protein synthesis
J. Castro-Montoya, A. Henke, J. Molkentin, K. Knappstein, A. Susenbeth, U. Dickhoefer
Animal Feed Science and Technology
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Animal Feed Science and Technology
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V. Fievez, E. Colman, J.M. Castro-Montoya, I. Stefanov, B. Vlaeminck
Animal Feed Science and Technology
V. Fievez, E. Colman, J.M. Castro-Montoya, I. Stefanov, B. Vlaeminck
Animal Feed Science and Technology
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Keyuan Liu, Xiaoyan Hao, Yang Li, Guobin Luo, Yonggen Zhang, Hangshu Xin
Asian-Australasian Journal of Animal Sciences
Keyuan Liu, Xiaoyan Hao, Yang Li, Guobin Luo, Yonggen Zhang, Hangshu Xin
Asian-Australasian Journal of Animal Sciences
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The relationships of dairy ruminal odd- and branched- chain fatty acids to the duodenal bacterial nitrogen flow and volatile fatty acids
Keyuan Liu, Yang Li, Guobin Luo, Hangshu Xin, Yonggen Zhang, Guangyu Li
Livestock Science
Keyuan Liu, Yang Li, Guobin Luo, Hangshu Xin, Yonggen Zhang, Guangyu Li
Livestock Science
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