Aquatic Animals

Salmon Lice Freshwater Treatment

Freshwater bathing is used to treat sea lice on farmed salmon, causing acute stress that raises welfare concerns about the treatment process.

Key Facts

Freshwater treatment kills sea lice by osmotic shock within minutes
Salmon experience significant stress during freshwater treatment as measured by cortisol levels
Treatment frequency increases as sea lice develop resistance to chemical treatments
Thermal treatments as an alternative to freshwater cause different acute stress patterns

Welfare Considerations

Freshwater and thermal treatments for sea lice cause significant acute stress in farmed salmon, representing welfare costs associated with necessary disease management. Salmon cannot move voluntarily through physiologically stressful conditions, making treatment stress unavoidable with current methods. Developing less stressful lice treatment methods and preventing lice infestation through closed containment systems would improve welfare outcomes.

What You Can Do

Support development of less stressful sea lice treatment methods
Advocate for transition to closed containment that eliminates sea lice infestation
Choose salmon from closed-containment producers where possible
Support research into lice prevention that avoids frequent stressful treatments