Spinal and jaw deformities are common in farmed salmon and cause chronic welfare problems that are amenable to hatchery management improvements.
Deformed fish experience permanent physical limitations including difficulty feeding, swimming, and competing for resources. A salmon with a severe spinal deformity may swim inefficiently and feed poorly throughout its entire life. Deformity prevention through optimal hatchery nutrition, water quality, and temperature management represents a welfare improvement that also improves production efficiency by reducing the proportion of fish with compromised performance.