Growth of wild and domesticated Atlantic cod Gadus morhua reared under semi-commercial conditions

• Published in: Aquaculture Environment Interactions
• Main Authors: Otterå, H, Heino, M, Sørvik, AGE, Svåsand, T, Karlsen, Ø, Thorsen, A, Glover, KA
• Format: Article in Journal/Newspaper
• Language: English
• Published: Inter-Research 2018
• Subjects: Aquaculture. Fisheries. Angling; SH1-691; Ecology; QH540-549.5; Arctic; Norway; Arctic cod; atlantic cod; Gadus morhua; Northeast Arctic cod
• Online Access: https://doi.org/10.3354/aei00262; https://doaj.org/article/ec48be32816e48dea1cb9e5b00ab551f

Genetic interactions between farmed escapees and wild fish represent a challenge to environmentally sustainable aquaculture. Breeding programs for Atlantic cod Gadus morhua have been initiated; however, the genetic response to selection, and therefore the degree of domestication, has not been evaluated. We compared growth of 2 wild and 2 partly domesticated strains that had been under selection for 2 generations. Offspring of 54 synchronously produced families were reared in 2 common-garden experiments, each consisting of Phase I: parallel rearing in mesocosms and tanks 0-8 mo post-hatch, and Phase II: rearing in tanks or sea-cages 8-18 and 8-34 mo post-hatch, respectively. One of the domesticated strains displayed significantly higher growth compared to the wild Northeast Arctic cod population (48-67% higher weight), while the other domesticated strain had a similar growth rate to the Northeast Arctic cod population. The wild population from southern Norway displayed a significantly higher growth rate compared to the wild Northeast Arctic cod population. These results represent the first experimental estimation of domestication-driven changes in farmed cod, and demonstrate that the first breeding programs for this species have been partially successful, resulting in improved growth rates of cod in 2 generations.