Feed trial will show if new diets can Pep up fish

New diets designed to make farmed seabass and gilthead sea bream more resilient to stress and bacterial infections are being evaluated for the first time under real production conditions.

The diets have been developed under Portugal’s Pep4Fish project, and are being trialled at Seaculture, a company owned by food retailer Jerónimo Martins’ production subsidiary, which also owns around a quarter of the equity in Norwegian land-based fish farmer Andfjord Salmon.

The trials are acting as the Pep4Fish project’s final demonstrator, assessing the performance of the new formulations at the facility in the Algarve.

Protein hydrolysates

The diets are enriched with new protein hydrolysates - innovative ingredients obtained by breaking down proteins from underutilised resources into compounds that are easier for fish to absorb. They work as advanced nutritional ingredients that help strengthen fish health, robustness and growth, while promoting more sustainable aquaculture feed in a circular bioeconomy.

ProHy, a new €20 million industrial unit dedicated to the valorisation of food by-products through innovative biotechnological processes, has been established as part of the project. Its production is based on a natural hydrolysis process , without the use of chemicals, which allows the conversion of animal by-products into high-value ingredients.

“We are evaluating fish performance with these new diets in a production environment, as initial laboratory results point to very positive indicators, particularly in terms of growth and reduced mortality rates,” says Pedro Encarnação, executive director of Seaculture.

Healthier fish

For Seaculture, the trial phase marks the transition from research to practical application, demonstrating how innovation in aquaculture nutrition can help address key industry challenges such as production system resilience, ingredient sustainability and fish quality.

“This project allows us to explore solutions that strengthen production sustainability while also promoting animal welfare. We believe that more robust and healthy fish also translate into a higher quality end product,” said Encarnação.

The ongoing trials represent a critical stage of the project, enabling the commercial-scale validation of the new diets ahead of potential wider adoption across the sector.