Decades of selective breeding have changed farmed Atlantic salmon physiology. Understanding genetic effects on welfare helps design better production systems for these fish.
Farmed salmon genetics affect welfare because extreme growth performance selection has created physiological vulnerabilities similar to those in broiler chickens. Skeletal deformities, heart problems, and immune vulnerabilities are more common in fast-growing domesticated lines. Breeding programs that explicitly incorporate health and welfare into selection criteria represent an important long-term welfare intervention for the industry.