Fish feed composition by high-throughput sequencing analysis: Parasite risk assessment

• Published in: International journal of food microbiology 2024-04, Vol.415, p.110633-110633, Article 110633
• Main Authors: Abollo, Elvira, Ramilo, Andrea, Pascual, Santiago
• Format: Article
• Language: English
• Subjects: Allergenic potential; Fish feed composition; High-throughput sequencing; Hysterothylacium; Parasite risk assessment; Phocanema
• ISSN: 0168-1605; 1879-3460
• DOI: 10.1016/j.ijfoodmicro.2024.110633

The use of wild small fish species as feed for aquaculture has clearly an economic incentive by speeding the growth of farmed species. Since feed ingredients are sourced from wild fisheries the farmed species could contain natural contaminants which may introduce food safety concerns. In this study, we used High-Throughput Sequencing (HTS) to explore the whole DNA profile of ten dry commercial feeds commonly used by Spanish fish farming companies. The feeds were mainly made of species within the genus Sprattus, Ammodytes and Clupea, and vegetables of the genus Triticum. In the feeds, DNA sequences of parasitic nematodes of fishes (˂1 % total OTUs) were also identified. A taxonomic assignment of query sequences, using a phylogeny-based approach, estimation of pairwise nucleotide identities within and between sequence groups and haplotype network analysis, allow assign short query sequences to the species Phocanema krabbei (Anisakidae) and Hysterothylacium aduncum (Rhaphidascarididae). Both species were identified as ingredient in two and six fish feeds, respectively. This result is of highly concern regarding dietetic recommendations to sensitized patients to anisakids, considering the growing evidence on the possible allergenic potential of both genera, and the recent data on the transfer of anisakid heat-resistant allergens from fishmeal to farm and aquaculture animals. •HTS data remarks the high dependence aquafeed manufacturing industry has on forage species.•Hysterothylacium aduncum and Phocanema krabbei were identified in 8 out of ten analysed feeds.•Genomic results complement previous works, as HTS revealed allergenic nematodes occurring in fish feed marketed in Spain.•The above finding is of highly concern regarding dietetic recommendations to sensitized patients to anisakids.