Abstract:

Residual feed intake (RFI) and methane (CH₄) emissions are potential new selection objectives in beef and sheep breeding programmes to assist reaching greenhouse gas mitigation targets and to support economic, social, and environmental sustainability. Phenotyping platforms in both species are in place in Uruguay, linked with the genetically evaluated populations of main breeds (Hereford, Merino, Corriedale, Dohne and Texel), being the basis of the reference populations for genomic selection. Current progress and main findings are described here. New selection indexes and selection criteria, as residual CH₄, are needed given the potential unfavourable associations between CH₄ and performance. Larger reference populations imply higher genomic prediction accuracies, accurate estimations of genetic correlations among feed intake, RFI, CH₄ and performance and a comprehensive understanding of these associations. On-going rumen metagenomics and metatrascriptomics will also provide information about its value as predictor of genetic merit of these traits.