Ornamental Fish Production and Management (1+1)

11.1.3 Selection

Selection is of greatest use in aquaculture and hatcheries. The mass selection, family selection and multiple trait selection make use of additive genetic variation for improvement of fish strains. The indirect selection, sib selection and progeny selection is used when the phenotype is difficult to measure. The mass, family and within family selections have been the main types of selection strategies employed so far in aquaculture for stock improvement. Mass selection is simple and works well only when the heritability is high and population is large so that large selection differentials can be employed.

Selective breeding is a breeding programme that tries to improve the breeding value of the population by selecting and mating only the best fish (largest, heaviest, those with the desired colour, etc.) in the hope that the select brood fish will be able to transmit their superiority to their offspring. If this occurs, the next generation will be more valuable because the fish will grow more efficiently, which will lower the feed costs; or all fish will have a more desired body colour, which will increase their market value.