Modeling breeding programs considering social behavior in large groups of farmed fish.

Area of Science:

• Aquaculture
• Animal Breeding
• Quantitative Genetics

Background:

• Social interactions are integral to aquaculture systems, influencing individual performance and breeding outcomes.
• Indirect genetic effects (IGEs) arising from social interactions can significantly alter selection responses in group-housed animals.
• Analyzing IGEs is critical for accurate genetic evaluations and effective breeding program design in aquaculture.

Purpose of the Study:

• To investigate the implications of heterogeneous social interaction effects on fish breeding programs.
• To evaluate how social interactions, influenced by target and personality traits, affect genetic gains and phenotypic variances.
• To compare the outcomes of different selection strategies under varying social interaction scenarios.

Main Methods:

• Stochastic simulations of a fish breeding program with 2000 selection candidates and 1000 families.
• Simulation of social interactions influenced by the target phenotype and two latent-personality traits.
• Analysis of genetic gains, phenotypic variances, and inbreeding rates under mass and group selection strategies.

Main Results:

• Increased social interaction effects enhance phenotypic variability in the target trait.
• Mass selection alters the genetic means of personality traits, contingent on genetic correlations.
• Group selection requires more groups with fewer families for equivalent genetic gain, maintaining target trait variability but increasing inbreeding rates.

Conclusions:

• Social interactions and indirect genetic effects are significant factors in fish breeding programs.
• Selection strategies must account for social interaction effects to optimize genetic gain and manage inbreeding.
• Understanding the interplay between target traits and personality traits under social influence is key for sustainable aquaculture breeding.