Sea lice infestations on farmed Atlantic salmon cause significant welfare harm through skin lesions, secondary infection, and stressful treatment procedures applied to control them.
Sea lice management is one of the most significant welfare challenges in salmon aquaculture. Both the infestation itself and the treatments used to control lice cause welfare harm. Thermal delousing systems that expose salmon to hot water cause heat shock. Chemical bath treatments cause oxidative stress. Mechanical removal using lasers or vacuum systems may be less harmful but are still aversive. Developing lice management strategies that minimize both infestation severity and treatment stress is a major priority in salmon welfare science.