| Probably the most challenging part of the environment of pigs is their social group. Social interactions profoundly affect the welfare and performance of pigs. Excessive aggression and oral manipulation of pen-mates can be detrimental, whereas affiliative relationships can be beneficial by offering ?social support?. Hence, (mal)adaptive responses of pigs in intensive pig husbandry not only affect their own welfare and performance, but also that of their group members. Until now, there has been a lack of attention for social interactions in the breeding program, as genetic selection for productivity traditionally targets the performance of the individual pig. This might favour the selection of animals that are competitive towards pen-mates. Recently, a novel selection method has been designed that considers both performance of an individual and its heritable social effect on performance of group members, by adding a ?social breeding value? to the genetic model. Because this method explicitly targets social interactions, it seems a promising route to achieve balanced genetic improvement of productivity and (social) behavioural traits relevant for welfare. The impact of social interactions will increase in the near future because tail-docking and castration are likely to be banned, resulting in increased risk of tail-biting and excessive aggression. This has created a sense of urgency for breeding companies either to incorporate social effects into the genetic model or to add behavioural traits to the breeding program. To improve welfare and productivity in a sustainable manner and to avoid undesired trade-offs, however, a better understanding of social genetic effects in pigs is needed. The consequences of novel selection methods as a strategy for ?seeking sociable swine? need to be explored, in relation to other, complementary, strategies that hold promise for reducing negative social interactions and enhancing positive ones, such as including behavioural and welfare-related traits into the breeding program and optimising the environment in which pigs are kept. Aim and outline projects Our aim is to study the opportunities to improve social interactions among pigs by incorporating social genetic effects in the breeding program and by investigating the implications of this novel selection method for behaviour and welfare. The (dis)advantages of this method and other complementary strategies will be explored, and future directions for welfare improvement through enhanced social performance will be formulated and implemented in collaboration with stakeholders (e.g. producers, food industry, retail, consumers, and animal welfare organisations). This should enable a balanced selection for sociable, productive pigs that are mentally and physically healthy. In this project, a science-society dialogue will be accomplished (Project 1) in synchrony with genetic and behavioural studies (Projects 2, 3 and 4). To ensure research directions that consider societal concerns, we will create a feedback-loop in which stakeholders and researchers share their disciplinary and experiential knowledge to define preferred directions along the research processes of Projects 2, 3 and 4 (Project 1). We will quantify the magnitude of genetic variation in social effects at various stages of a pig?s life and the genetic relationships between social effects in those stages (Project 2). The effects of the novel selection method on behaviour, health and welfare will be studied, as well as the impact of group composition and coping styles (Project 3). As the consequences of the novel selection method also depend on the environment, genotype by environment interactions on underlying traits will be studied under different conditions. This will reveal whether adding social genetic effects to the genetic model yields pigs that are adapted to a specific, suboptimal environment or in pigs with improved (social) adaptability in a larger range of environments (Project 4). The close involvement of a breeding organisation, pig farmers and other stakeholders in the research program will shorten the time needed to implement strategies for obtaining sociable pigs which contributes to improved pig welfare. |
