The objectives of this study were to estimate genetic parameters for lactation efficiency (LE), its underlying traits, and to predict the consequences of current selection strategies in dam lines. Inclusion of LE in the breeding goal will improve stayability, as defined by the first-litter survival of sows and LE itself, without
negative consequences for other economically important traits. Nevertheless, it might be worthwhile to
design a breeding goal in which LE increases and feed intake remains unchanged.