Genetics of adaptation in fish : effects of domestication, stress resistance and adaptation to the environment

Abstract

The genetic variation of the adaptation of fish to their farm environment is an important topic in the question of farm animal welfare. Three main aspects are studied: (i) the question of domestication, which is ongoing or to be done in many fish species; domesticated fish are better adapted to farming (better access to feed, less stress-sensitive), but lose some behaviours which are useful in the wild (predator avoidance); (ii) selection for stress resistance, which is efficient and seems to have some effects quite similar to those of domestication; (iii) adaptation to the environment, the genetic component of which seems quite important. From all the data studied, it seems possible to select fish which will be better adapted to farming. However, the high environmental sensitivity of fish will make the integration of the genotype by environmental interactions necessary when studying the effects of breeding practices on adaptation.