As part of a review of future research and development possibilities in the area of swine reproductive biology and breeding herd management (Foxcroft, 2012), a number of key areas of future interest were identified. One centred around the gene x environment interactions that determine the final phenotype of production-level progeny in mature sow populations. Understanding the mechanistic basis for the observed gene x environment interactions that drive “litter of origin” effects on post-natal performance has been an important part of our research program. The outcomes from these studies suggest ways to identify litter phenotypes and to create production strategies to address existing “phenotypic plasticity”. The possibility of using a nutrigenomic approach to offset such programmed effects has also been explored. At a more basic level, the goal is to find genomic/epigenomic markers for the key biological traits that drive these gene x environment outcomes, with the aim of including genetic markers for these component traits in more sophisticated breeding programs that deliver replacement gilts for commercial production.

A second area of focus was driven by recent opportunities, at least in North and South America, to determine individual boar fertility in large commercial boar studs. This constitutes the first step in improving the impact of genetically superior sires on the number, and particularly the quality, of commercial progeny. At the same time, access to fertility data from large populations of terminal-line boars enables association analyses that will hopefully allow genomic and proteomic markers of boar fertility to be identified. A more detailed discussion of recent collaborative studies on boar fertility will be presented by Amanda Minton in Breakout # 11 at this meeting. As part of this74 Foxcroft et al presentation, data from the same collaborative studies will be used to identify the extent to which variability in boar fertility, and current AI practices in the industry, has probably been limiting the performance of outstanding dam-line females.