Investigating the contribution of social genetic effect to longer selection response in a ten generations breeding programme simulated

Abstract

Social interactions among animals are general phenomena in domestic populations. However, at present, very little is known about the contribution of social effect to the selection efficiency of long-term response. In this study, the selection efficiency of a socially affected trait with different social effect was investigated in a closed nucleus population using stochastic simulation. Some key factors that affect selection efficiency of genetic social effect were also compared. The results showed social effect played an important role in a longer term breeding programme even though social effect had a small effect on the trait of interest. The percentage of expected total response contributed by social effect was up to 15.27 at the end generation under a very low level of social effect (0.3% direct phenotypic variance). The full model with direct and social genetic effect, improved the selection efficiency of social effect and resulted in 4.89, 5.21 and 2.70% more total cumulative selection response than the reduced model, without social effect, under the social effect size of 0.3, 1 and 10% direct phenotypic variance, respectively. The social effect size and group member number showed more effect on the selection efficiency of social effect than other factors.