There is no particular event that can be linked to the high mortality rates, but three health challenges stand out in farmed salmon in 2022: delousing injuries, complex gill disease, and winter ulcer. While the number of detections of serious viral diseases has stabilised, there are concerns about the development of bacterial diseases. In particular, the high prevalence of winter ulcer represents an important animal welfare concern.
Norwegian Fish Health Report 2022
Several reports have highlighted the unprecedented number of farmed salmonids lost in the on-growing seawater farms in 2022. However, high losses also occurred in the land-based juvenile production phase. In total, 92.3 million Atlantic salmon and 5.6 million rainbow trout died before reaching slaughter size in 2022.