TY - JOUR
DP - National Agricultural Library
DB - PubAg
JO - Animal feed science and technology
TI - Relationships between odd- and branched-chain fatty acid profiles in milk and calculated enteric methane proportion for lactating dairy cattle
A1 - Montoya, J. Castro
A4 - Montoya, J. Castro
A4 - Bhagwat, A.M.
A4 - Peiren, N.
A4 - De Campeneere, S.
A4 - De Baets, B.
A4 - Fievez, V.
EP - 2011 v.166-167
KW - algorithms
KW - branched chain fatty acids
KW - correlation
KW - dairy cows
KW - data collection
KW - emissions
KW - fatty acid composition
KW - feeds
KW - foods
KW - greenhouse gases
KW - lactation
KW - least squares
KW - linear models
KW - methane
KW - methane production
KW - milk
KW - prediction
KW - rumen
KW - stoichiometry
KW - variance
KW - volatile fatty acids
AN - 473963
AB - The purpose of this study was to explore the relationships between odd- and branched-chain fatty acids (OBCFA) in milk with calculated enteric CH₄ production for lactating dairy cows using multiple linear regression (MLR), partial least squares regression (PLS) and a genetic algorithm approach (GA). A dataset collected from 13 experiments containing 224 paired observations of measured acetate, propionate and butyrate proportions in rumen fluid VFA and 7 measured OBCFA was used. Methane proportion (mmol/mol VFA) was calculated from acetate, propionate and butyrate and expressed relative to the sum of these volatile fatty acids (VFA). Calculated CH₄ production was related to milk OBCFA using MLR and PLS, resulting in a linear prediction model. The GA approach resulted in a model which predicted rumen VFA proportions of total VFA from milk OBCFA. Methane proportion was calculated from predicted acetate, propionate and butyrate proportions in total VFA based on rumen stoichiometry and compared with CH₄ proportion calculated from measured VFA proportions. The prediction error was low (i.e., root mean square prediction error <5%), and models captured up to 66% of the variance in the data and the concordance correlation coefficient was close to 0.8. The variance of the prediction error was less than 40% of the variance of the calculated CH₄ proportion. Seven milk OBCFA were initially considered as predictors, from which the branched-fatty acids iso C14:0, iso C15:0, iso C16:0 were positively related to calculated enteric CH₄ production and the odd-fatty acids C15:0 and the sum of C17:0 and C17:1 cis–9 were negatively related to it. Relationships in this large data set identify the most relevant OBCFA in milk as potential predictors of rumen methanogenesis. This paper is part of the special issue entitled: Greenhouse Gases in Animal Agriculture – Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors; K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson.
PY - 2011
LA -
DA - 2011-06-23
VL - v. 166-167
SP - pp. 596-602
DO - 10.1016/j.anifeedsci.2011.04.080
ER -