Disease management in farmed seabream and seabass is a significant welfare challenge. Major pathogens including sea lice, VHS, and bacterial infections require welfare-conscious management approaches.
Disease welfare in Mediterranean farmed fish involves both the direct suffering caused by pathogens and parasites and the welfare impact of treatment interventions. Gill parasites cause respiratory compromise reducing oxygen availability - the equivalent of partial suffocation in affected fish. Bacterial infections cause haemorrhagic lesions and systemic disease with significant welfare impact. Vaccination programmes have reduced reliance on antibiotics, improving both welfare (through disease prevention) and sustainability. Treatment with antiparasitic compounds involves handling stress. Prevention through biosecurity, vaccination, and optimal water quality is both more welfare-positive and more cost-effective than reactive treatment of established disease.