Relationship between rumen odd and branched chain fatty acids and fermentation characteristics as studied in vitro

Abstract

Rumen microbes contain a high proportion (20 to 50%) of their fatty acids (FA) as odd and branched chain fatty acids (OBCFA; C15:0, iso C15:0, anteiso C15:0, C17:0; iso C17:0; anteiso C17:0 and C17:1) and different bacterial classes have distinctive OBCFA ‘fingerprints’. As OBCFA make up around 5% of FA in milk, it has been suggested that there is scope for these compounds to be used in on-farm diagnostic milk-based tests in relation to the rumen fermentation pattern. Correlations of milk OBCFA with rumen fermentation pattern were recently shown (Vlaeminck et al., 2002). In the current in vitro study, the potential of rumen OBCFA to predict the production of volatile fatty acids (VFA) was evaluated.