Compensation of Loss in Genetic Gain Due to Genotype by Environment Interaction by Increasing the Size of the Breeding Nucleus in an Aquaculture Population

Abstract Text:

We studied how much the size of a breeding nucleus must be increased to compensate for the loss in genetic gain due to genotype environment interaction (GxE). With truncation selection at a predefined rate of inbreeding for a trait recorded on candidates in the nucleus only, the number of families must increase substantially even with low GxE. When the trait can also be recorded on sibs in the commercial grow-out environment, increases in number of families are less. If the trait cannot be recorded on the selection candidates, preliminary results indicate that the increase in size of the breeding nucleus is marginal. The type of traits in the breeding objective may therefore have a large impact on whether the cost of increasing the size of the breeding nucleus become higher than establishment of a second breeding nucleus in an important market.

Keywords:

Aquaculture

Genotype by environment interaction

Breeding program