Is thermal delousing welfare-friendly?
Two new studies focusing on Atlantic salmon’s tolerance to thermal delousing indicate that the method may not be as welfare friendly as initially thought. Researchers evaluating the methods reported extensive tissue injuries and pain responses in the salmon used in the experiments.
Based on the evidence in the trials, the researchers concluded that Atlantic salmon find exposure to warm seawater highly aversive. They also concluded that the aversive reactions could be attributed to the sudden change in temperature, not the presence of other fish in their environment or manual handling.