A case study on farmed European seabass and gilthead seabream in Central Italy: the negligible parasitological risk of nematode larvae paves the way for the freezing derogation

Abstract Gilthead seabream and European seabass are among the most appreciated farmed fish species in the European Union. This case study analysed the self-control plan procedures adopted in an offshore cage farm in Central Italy to prevent anisakids infection, in the light of the Anisakis contamination pathways previously proposed for farmed Atlantic salmon (Salmo salar), and of the criteria recommended by the European Food Safety Authority. Moreover, the results of the visual parasitological examination conducted by the Food Business Operator, as part of the self-control plan, on 5% of the total specimens with commercial size (2016-2020 period) were also considered. Results show an extremely low to negligible risk for the introduction of ascaridoid larvae, confirming the absence of these parasites in farmed specimens of both species. However, few implementations to the self-control plan are suggested for obtaining the derogation to preventive freezing, as established by the European legislation. These include the parasitological examination of a statistically significant sample of the farmed specimens (commercial sizes) conducted by trained personnel, as well as of farmed specimens found dead or underdeveloped (runts) and of wild specimens of other species which may enter the cages. The proposed approach can be adapted by other farms by adjusting the sample size based on the production volume and risk categorization. The exemption from the preventive freezing would represent an additional market opportunity for Italian aquaculture plants.