An increase in selection intensity, results in an increase in genetic gain. Fast genetic gain can thus be achieved by selecting only the very few, the very best animals for breeding. Apart from the fact that the reproductive capacity will determine the minimum number of animals that need to be selected in order to maintain population size, there is another important issue: inbreeding. The rate of inbreeding in a population can be predicted by 1/8Nm + 1/8Nf and that a smaller number of parents thus results in a higher rate of inbreeding. This is especially the case with unbalanced numbers of males and females. If we use the recommendation of the FAO not exceed that the rate of inbreeding of should not exceed 0.5 to 1% for the population to remain viable, this may have consequences for the selection strategy.
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