Principles of Genetics and Breeding

13.1.4. Base population

The genetic management of the organisms used in aquaculture have received relatively little attention compared to effort taken to improve farm strains of terrestrial animals and plants.

The situation with farmed aquatic organisms is unique in that the vast majority are still effectively genetically wild.

Most of the species are captured from the wild to supply broodstock for hatcheries or fry for on growing even today. For e.g. Penaeid prawns, milk fish, Indian and Chinese carps.

Even in Europe the majority of the species used in aquaculture have only recently had their life cycles closed by the farmer (e.g. Atlantic salmon, European seabass and sea bream). It is still common even in these species for farmers to rely on wild caught fish to boost broodstock numbers.

Once the life-cycle is completely closed the major problems associated with poor broodstock management come to light.

Hatchery managers of any farmed species should strive to produce not only fit, disease free fry, but, they should also produce fish with the best possible genetic potential to fulfill the needs of the on grower. However, there is a growing body of evidence that many hatchery strains of fish have been genetically compromised because of poor husbandry and broodstock practices.

When starting selective breeding, the genetic base have to be considered. The genetic variation in the base population is secured by developing a synthetic population by testing several unrelated populations before the best performing population was selected and mated together as base population.