Author(s):
Marmelo, Isa ; Chainho, Tomás ; Bolotas, Daniel ; Pereira, Alícia ; Özkan, Busenur ; Marques, Cátia ; Silva, Iris A.L. ; Soares, Florbela ; Pousão-Ferreira, Pedro ; Vieira, Elsa F. ; Delerue-Matos, Cristina ; Silva, Zélia ; Videira, Paula A. ; Repolho, Tiago ; Diniz, Mário Sousa ; Marques, António ; Maulvault, Ana Luísa
Date: 2025
Persistent ID: http://hdl.handle.net/10362/187540
Origin: Repositório Institucional da UNL
Project/scholarship:
info:eu-repo/grantAgreement/FCT/3599-PPCDT/PTDC%2FCTA-AMB%2F0592%2F2021/PT;
info:eu-repo/grantAgreement/FCT/Concurso de avaliação no âmbito do Programa Plurianual de Financiamento de Unidades de I&D (2017%2F2018) - Financiamento Base/UIDB%2F04378%2F2020/PT;
info:eu-repo/grantAgreement/FCT/Concurso para Atribuição do Estatuto e Financiamento de Laboratórios Associados (LA)/LA%2FP%2F0140%2F2020/PT;
info:eu-repo/grantAgreement/FCT//2020.04413.BD/PT;
Subject(s): aquaculture; disease outbreaks; extreme weather events; functional feeds; hematological parameters; immune response; leukocyte viability; macroalgae; macroalgae extracts; vibriosis; Ecology, Evolution, Behavior and Systematics; Renewable Energy, Sustainability and the Environment; Environmental Science(all); SDG 7 - Affordable and Clean Energy; SDG 13 - Climate Action; SDG 14 - Life Below Water
Description
The authors acknowledge the team from the Aquaculture Research Station of Olh\u00E3o (EPPO\u2013IPMA I.P.) for the technical support provided during animal rearing and transplantation, as well as Leonardo Mata from GOPSIS Lda. for supplying the macroalga Laminaria digitata and Jorge Dias from SPAROS Lda. for supplying the experimental aquafeeds. T.C. acknowledges the BLUE BIOECONOMY INNOVATION PACT\u2013Vertical Algas project (C644915664-00000026) for his research fellowship. D.B. acknowledges the NextGenerationEU program under the Recovery and Resilience Facility Plan for Portugal\u2013Agenda VIIAFOOD\u2013Platform for Valorization, Industrialization, and Commercial Innovation for the Agri-Food Sector (C644929456-0000004) for his research fellowship. A.P. acknowledges the INNOECOFOOD project (101136739, Horizon Europe) for her research contract. Copyright: © 2025 by the authors. Licensee MDPI, Basel, Switzerland.
Extreme weather events, such as marine heatwaves (MHWs), pose serious threats to the aquaculture sector, facilitating the occurrence of disease outbreaks and compromising farmed animals’ welfare and survival. Hence, finding eco-innovative strategies to improve animal immunocompetence is essential to assure aquaculture’s sustainability and resilience in a rapidly changing ocean. This study evaluated the immunostimulatory potential of Laminaria digitata powder (0.3% and 1.5%) and extract (0.3%) in juvenile gilthead seabream (Sparus aurata) exposed to a Vibrio harveyi outbreak during a Category III MHW event (T = 25.7 °C). Overall, L. digitata supplementation did not significantly affect fish immunocompetence under optimal rearing conditions (T = 21.4 °C; no infection), nor did it induce any adverse effects. However, both the powder (1.5%) and extract (0.3%) forms of L. digitata supplementation effectively mitigated the negative impacts prompted by the MHW and Vibrio harveyi infection—evidenced by improvements in fish health indicators, hematological parameters, leukocyte viability, granulocyte proportions, and reductions in peroxidase activity and immunoglobulin M levels. From an economic standpoint, supplementation with 1.5% L. digitata powder emerged as the most promising strategy, offering a practical balance between effectiveness and affordability for large-scale applications. These findings highlight the potential of L. digitata as an immunostimulatory aquafeed supplement, with promising benefits for fish health and resilience under adverse rearing conditions.
