Computer simulations of the genetic load
Finally, we performed computer simulations examining the impact of genomics-informed captive breeding on the neutral nucleotide diversity, genetic load, realised load, and fitness of individuals. The ”Random mating” and “Minimise relatedness” regimes showed a steady increase in genetic (Fig. 5A) and realised (Fig. 5B) load over generations. Both regimes also suffered from a large decline in fitness due to a mutation meltdown (Fig. 5C). In contrast, both the genetic load and realised load were reduced in “Minimise load” and “Minimise load and relatedness” regimes (Fig. 5A,B). Therefore, genomics-informed captive breeding can effectively purge deleterious mutations and reduce their homozygosity, independently of consideration of relatedness. Consequently, mean fitness remained high in these regimes, increasing during the first ten generations (Fig. 5C). However, populations lost neutral genetic diversity at a relatively fast rate in the “Minimise load” regime (Fig. 5D). Such loss in diversity was not observed in the “Minimise load and relatedness” regime, and after ∼10 generations, this regime maintained more diversity than the “Random mating” regime (Fig. 5D).