an estimate of this genetic quality

The genetic ability or merit of an animal for a given trait, for example, secreting milk. One-half of this genetic ability is transmitted to offspring.

In quantitative genetics, the part of the deviation of an individual phenotype from the population mean that is due to the additive effects of alleles. In practical terms: if an animal is mated with a random sample of animals from a population, that animal's breeding value for a certain trait is twice the average deviation of its offspring from the population mean for that trait.

Value of an animal as a parent. The working definition is twice the difference between a very large number of progeny and the population average when individuals are mated at random within the population and all progeny are managed alike. The difference is doubled because only a sample half (one gene of each pair) is transmitted from a parent to each progeny. Breeding value exists for each trait and is dependent on the population in which the animal is evaluated. For a given trait, an individual pig can be above average in a population defined one way, and below average in a population defined another way.

(1) The value of an individual as a (genetic) parent. (2) The part of an individual's genotypic value that is due to independent and therefore transmittable gene effects.