Anisakis spp. larvae in black scabbardfish (Aphanopus carbo) muscle: Consumer health risk and recommendations along the value chain

The black scabbardfish, <i>Aphanopus carbo</i>, is a deep-sea Atlantic fish with socioeconomic value, but it is often heavily infected with <i>Anisakis</i> spp. larvae. The aim of the present work was to ascertain the distribution and quantification of <i>Anisakis</i> spp. larvae in the viscera and muscle of <i>A. carbo</i>, and to evaluate whether larval intensity in the viscera can be used to predict parasite load in the muscle. UV-press and pepsin-HCl digestion methods were complemented by molecular techniques to detect and identify the larvae. Four batches of four individuals each, one batch per season (<i>n</i> = 64), were obtained. Each batch, with a different parasite intensity based on visual inspection, was selected for comparison. Larval subsamples randomly selected from the viscera, belly flaps, and dorsal muscle were identified by PCR-RFLP, marking the first study of this kind in this species. Data showed that the higher the larval load in the visceral cavity and internal organs, the greater the number of larvae in the belly flaps, allowing us to predict <i>Anisakis</i> burden in this site. The low number and unpredictability of the zoonotic <i>A. simplex s.s</i> in the dorsal muscle pose a risk to consumers. Epidemiological data support discarding the belly flaps from fish with relatively high parasite intensity. Additional recommendations to mitigate anisakids presence in fishery products are presented for improvement and implementation along the black scabbardfish value chain.