Exploring the potential to breed for positive social behaviour to improve animal welfare and efficiency

About the Project

In livestock production, harmful social behaviours are a persistent problem. In pig farming, this includes aggression and tail biting, compromising physical and psychological animal welfare. In addition, these behaviours also reduce immunocompetence, feed efficiency and growth, therefore directly reducing the efficiency of production, with negative effects on sustainability. While environmental manipulations in pig farming can reduce these negative behaviours, these are often costly and impractical to implement at scale. In contrast, pigs also show a range of prosocial positive behaviours that are likely to have a positive impact on welfare.

There is considerable individual variation in the expression of social behaviour. Therefore, animal breeding offers great potential to cumulatively and permanently improve social behaviours. However, doing so relies on the availability of large datasets to firstly quantify the genetic architecture of the traits and the likely impact on economic production traits. This project will quantify the genetic basis to social behaviours in pigs, focussing on both positive and negative forms of interaction. It will exploit existing datasets that are globally unique in the number and richness of behavioural records on genotyped animals. The study will focus on pigs as they are cognitively advanced, display a wide repertoire of social behaviours and because they show harmful behaviours that are particularly detrimental to their welfare and the environment.

The project is a partnership between Queen’s University Belfast, Scotland’s Rural College and the largest pig breeding company in the world (Pig Improvement Company) responsible for providing genetics for around 300 million pigs per annum. The PhD provides excellent exposure to industry and PIC is committed to implementing selection to improve social behaviour, so this project is expected to lead to direct welfare benefits.

The project will make use of two existing datasets on genotyped pigs where behavioural phenotypes have been extracted from detailed sampling of video images by trained observers. To our knowledge, no comparable resource exists anywhere that unites detailed social behavioural phenotypes with pedigree and genomic data on a large sample of animals. These datasets are also unique in quantifying not only negative social behaviours, but positive social behaviours and the ability to adapt to a dynamic social environment.

The project will address the following four objectives.

1. Quantify the heritability of a wide range of positive and negative social behaviours (i.e. the extent to which they are genetically determined) and identify the genomic regions responsible for underlying trait variation.
2. Quantify the genetic correlations between different social behavioural traits to understand how improving one behaviour may affect other behaviours.
3. Quantify the genetic correlation between social behavioural traits and economic production traits to understand how improving behaviour may positively or negatively affect production.
4. Model the optimum strategy for inclusion of behavioural traits in a selection index.