{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T09:50:33Z","timestamp":1775641833890,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2023,12,6]],"date-time":"2023-12-06T00:00:00Z","timestamp":1701820800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"AQUARAS","award":["MAR-02.01.02-FEAMP-0223"],"award-info":[{"award-number":["MAR-02.01.02-FEAMP-0223"]}]},{"name":"AQUARAS","award":["2021.01458.CEECIND"],"award-info":[{"award-number":["2021.01458.CEECIND"]}]},{"name":"Foundation for Science and Technology","award":["MAR-02.01.02-FEAMP-0223"],"award-info":[{"award-number":["MAR-02.01.02-FEAMP-0223"]}]},{"name":"Foundation for Science and Technology","award":["2021.01458.CEECIND"],"award-info":[{"award-number":["2021.01458.CEECIND"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>There are a high number of stressors present in aquaculture that can affect fish welfare and quality. One way of mitigating stress response is by increasing dietary tryptophan. In this study, three diets containing 0.5% (Tript1), 0.6% (Tript2), and 0.8% (Tript3) of tryptophan were tested in 32 g juvenile meagre for 56 days. At the end of the trial, survival, growth, and proximate composition were similar between treatments. Significant differences were found in the plasma parameters before and after a stress test consisting of 30 s of air exposure. Blood glucose levels were higher in the post-stress for all treatments (e.g., 63.9 and 76.7 mg\/dL for Tript1 before and after the stress test), and the hemoglobin values were lower in the post-stress of Tript1 (1.9 g\/dL compared to 3.0 and 2.4 g\/dL for Tript2 and Tript3, respectively). In terms of behavior, three tests were carried out (novel tank diving and shoaling assays, and lateralization test), but no significant differences were found, except for the number of freezing episodes during the anxiety test (1.4 for Tript3 compared to 3.5 and 4.2 for the other treatments). This study suggests that supplementation with dietary tryptophan, particularly in higher dosage (0.8%), can reduce anxiety-like behavior in meagre exposure to acute stress (novel tank). Although the remaining results showed mild effects, they provide some clues as to the potential of this amino acid as a stress mitigator in aquaculture.<\/jats:p>","DOI":"10.3390\/ani13243762","type":"journal-article","created":{"date-parts":[[2023,12,6]],"date-time":"2023-12-06T06:01:07Z","timestamp":1701842467000},"page":"3762","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Effect of Tryptophan Dietary Content on Meagre, Argyrosomus regius, Juveniles Stress and Behavioral Response"],"prefix":"10.3390","volume":"13","author":[{"given":"Ana","family":"Vasconcelos","sequence":"first","affiliation":[{"name":"Faculdade de Ci\u00eancias da Universidade do Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5213-2377","authenticated-orcid":false,"given":"Marta C.","family":"Soares","sequence":"additional","affiliation":[{"name":"CIBIO\u2014Centro de Investiga\u00e7\u00e3o em Biodiversidade e Recursos Gen\u00e9ticos, InBIO Laborat\u00f3rio Associado, Universidade do Porto, 4169-007 Porto, Portugal"},{"name":"BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, 4485-661 Vair\u00e3o, Portugal"},{"name":"MARE\u2014Centro de Ci\u00eancias do Mar e do Ambiente, ARNET\u2014Rede de Investiga\u00e7\u00e3o Aqu\u00e1tica, Departamento de Paisagem, Universidade de \u00c9vora, Ambiente e Ordenamento, 7004-516 \u00c9vora, Portugal"}]},{"given":"Marisa","family":"Barata","sequence":"additional","affiliation":[{"name":"Aquaculture Research Station of IPMA, Av. Do Parque Natural da Ria Formosa, 8700-194 Olh\u00e3o, Portugal"}]},{"given":"Ana","family":"Couto","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4050-208 Matosinhos, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1953-5120","authenticated-orcid":false,"given":"B\u00e1rbara","family":"Teixeira","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4050-208 Matosinhos, Portugal"},{"name":"Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Division of Aquaculture, Upgrading and Bioprospection, 1495-165 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0110-8860","authenticated-orcid":false,"given":"Laura","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"Aquaculture Research Station of IPMA, Av. Do Parque Natural da Ria Formosa, 8700-194 Olh\u00e3o, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6746-764X","authenticated-orcid":false,"given":"Pedro","family":"Pous\u00e3o-Ferreira","sequence":"additional","affiliation":[{"name":"Aquaculture Research Station of IPMA, Av. Do Parque Natural da Ria Formosa, 8700-194 Olh\u00e3o, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4272-865X","authenticated-orcid":false,"given":"Rog\u00e9rio","family":"Mendes","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4050-208 Matosinhos, Portugal"},{"name":"Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Division of Aquaculture, Upgrading and Bioprospection, 1495-165 Lisbon, Portugal"}]},{"given":"Margarida","family":"Saavedra","sequence":"additional","affiliation":[{"name":"Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, 4050-208 Matosinhos, Portugal"},{"name":"Portuguese Institute for the Sea and Atmosphere, I.P. (IPMA), Division of Aquaculture, Upgrading and Bioprospection, 1495-165 Lisbon, Portugal"},{"name":"MARE\u2014Marine and Environmental Sciences Centre & ARNET\u2014Aquatic Research Network Associated Laboratory, NOVA School of Science and Technology, NOVA University of Lisbon, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,6]]},"reference":[{"key":"ref_1","unstructured":"FAO (2019). 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