8.1.1: Mass selection (2024)

The most basic way is to rank the animals according to their phenotype and select the best ones for breeding. This method is also called Mass Selection, or Selection on Own Performance. For example, of you want to breed large rabbits, then you rank the animals according to size and only use the largest as parents for the next generation. The success of this type of selection depends on the heritability. This is the indication of how much of the variation in phenotypes you observe are caused by genetic variation among the animals. A high heritability indicates that the small rabbits most likely are small because they have lower genetic potential for growth than the larger rabbits. The better the phenotype provides a representation of the genotype, the better you are able to identify the genetically best animals, and thus the better the results of mass selection will be. In addition, an important prerequisite is that own performances are available.

In fish mass selection is often applied, because identification is not always possible and the pedigree and relationships with other individuals in the same basin cannot be used for breeding value estimation.