The main aim of this study was to elucidate whether rumen microbial gene abundances (RMGA) can be used to predict residual feed intake (RFI), feed conversion ratio (FCR) and its component traits: daily feed intake (DFI), average daily gain (ADG), and thus RMGA could be applied as indirect trait for breeding of feed efficiency in beef cattle. RMGA were generated by whole metagenomic sequencing of rumen microbial DNA samples from 42 beef cattle, with extreme low and high FCR, selected from two feed efficiency trials. The results of the PLS analysis indicated that RMGA showed substantial potential to be used as predictors for RFI, FCR and its components DFI and ADG explaining 55 to 73% of their variation. While only 12 and 23 microbial genes were significantly associated with RFI and DFI, respectively, there were 166 and 167 affecting ADG and FCR. RFI and DFI were influenced partly by the same microbial genes and combined in the same microbial network clusters as was also the case for FCR and ADG. The results elucidate the likely potential of RMGA to predict the difficult and costly to measure trait feed efficiency, but have to be confirmed under the more challenging conditions of practical breeding programmes. Keywords: feed efficiency, growth, microbiome, metagenomics, genetic improvement

Rainer Roehe, Marc Auffret, Andrew Southwell, Carol-Anne Duthie, John Rooke, John Wallace, Tom Freeman, Tim Snelling, Robert Stewart, Mick Watson, Richard Dewhurst

Proceedings of the World Congress on Genetics Applied to Livestock Production, Volume Biology - Feed Intake and Efficiency 1, , 865, 2018
Download Full PDF BibTEX Citation Endnote Citation Search the Proceedings

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.