Effect of Organic and Nano Selenium Dietary Supplementation on Growth, Survival, Feed Utilization, Gastrointestinal Health, and GPx Enzyme Activity of Gilthead Sea Bream (Sparus aurata) Larvae

Effect of Organic and Nano Selenium Dietary Supplementation on Growth, Survival, Feed Utilization, Gastrointestinal Health, and GPx Enzyme Activity of Gilthead Sea Bream (Sparus aurata) Larvae | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Effect of Organic and Nano Selenium Dietary Supplementation on Growth, Survival, Feed Utilization, Gastrointestinal Health, and GPx Enzyme Activity of Gilthead Sea Bream (Sparus aurata) Larvae Alaa A. El-Dahhar, Ahmad Abdel-Salam, Samy Y. EL-Zaeem, Mohamed M. Abdel-Rahim, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8005446/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract In this study, gilthead sea bream (G. Sea bream) larvae were fed three different micro diets (MD) during the weaning period, each containing 51.7% crude protein. The diets included: an MD supplemented with 4 mg of organic selenium per kilogram (Org-Se), an MD supplemented with 0.3 mg of nano-selenium per kilogram (Nano-Se), and a control MD without Selenium supplementation (C). The hatched larvae were fed live food (microgreen algae, rotifers, and Artemia) in addition to the MD. Using nine 5 m³ fiberglass tanks under a greenhouse, the experiment began with G. Sea bream larvae at 20 days post-hatch (DPH) and continued until the end of the trial at 60 DPH. The brood fish from which the larvae were derived received the same Selenium forms and doses in their basal diets, which consisted of a mix of 45% protein dry feed, squid, and sardines. Data on the broodstock and their offspring were reported in a separate research paper. The larvae, initially weighing 2.4 mg and measuring 4.5 mm in length, were replicated three times across the three treatments, with 50,000 larvae per tank (4 m 3 of seawater). The larvae fed the Nano-Se diet exhibited a higher survival rate of 57.43%, compared to 54.76% for those on the Org-Se diet and 53.73% for the control diet (P < 0.01). The Nano-Se diet also produced the highest growth indices (FBW, SGR, FTL, and condition factor, K) and surpassed both the control and Org-Se diets. However, differences among the three treatments were not significant for FCR and PER (P > 0.05). The study showed that the GPx enzyme activity in 20 DPH larvae from broodstock fed the Nano-Se diet was 10.34 U/mg of protein, significantly higher than that of larvae fed the Org-Se diet (9.36 U/mg of protein) and the control diet (8.81 U/mg of protein) (P ≤ 0.05). Additionally, after 60 DPH, the larvae on the Nano-Se diet exhibited the highest GPx enzyme activity at 17.6 U/mg of protein, followed by the Org-Se at 15.54 U/mg of protein and the control diet at 13.33 U/mg of protein (P < 0.01). Biological sciences/Biochemistry Biological sciences/Ecology Earth and environmental sciences/Ecology Earth and environmental sciences/Environmental sciences Earth and environmental sciences/Ocean sciences Biological sciences/Zoology Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8005446","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":545764378,"identity":"abf236f7-293d-4b3f-a29f-4214e7e81b1f","order_by":0,"name":"Alaa A. El-Dahhar","email":"data:image/png;base64,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","orcid":"","institution":"Alexandria University","correspondingAuthor":true,"prefix":"","firstName":"Alaa","middleName":"A.","lastName":"El-Dahhar","suffix":""},{"id":545764379,"identity":"1c1e5ed2-4627-4581-b7b0-cb1cfcb1e3a3","order_by":1,"name":"Ahmad Abdel-Salam","email":"","orcid":"","institution":"General Authority for Fish Resources Development (GAFRD)","correspondingAuthor":false,"prefix":"","firstName":"Ahmad","middleName":"","lastName":"Abdel-Salam","suffix":""},{"id":545764380,"identity":"416fb602-9456-411b-9658-c6be3699e810","order_by":2,"name":"Samy Y. EL-Zaeem","email":"","orcid":"","institution":"Alexandria University","correspondingAuthor":false,"prefix":"","firstName":"Samy","middleName":"Y.","lastName":"EL-Zaeem","suffix":""},{"id":545764382,"identity":"5fd9ee3b-cc5c-4f01-8cf7-359039a71305","order_by":3,"name":"Mohamed M. Abdel-Rahim","email":"","orcid":"","institution":"National Institute of Oceanography and Fisheries (NIOF)","correspondingAuthor":false,"prefix":"","firstName":"Mohamed","middleName":"M.","lastName":"Abdel-Rahim","suffix":""},{"id":545764384,"identity":"8330c8de-0a73-4084-8de9-d335919af45a","order_by":4,"name":"Mona M. Mourad","email":"","orcid":"","institution":"National Institute of Oceanography and Fisheries (NIOF)","correspondingAuthor":false,"prefix":"","firstName":"Mona","middleName":"M.","lastName":"Mourad","suffix":""}],"badges":[],"createdAt":"2025-11-01 11:53:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8005446/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8005446/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":96090988,"identity":"eb779550-c29b-4d18-9a65-183efdfd75cc","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":352675,"visible":true,"origin":"","legend":"","description":"","filename":"Figures.docx","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/d0505c90e680a6f7bdad9d96.docx"},{"id":96246804,"identity":"edbd3d5b-3e43-49de-bbbe-f72cd3116ccf","added_by":"auto","created_at":"2025-11-19 07:26:43","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":117899,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.docx","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/00d0bde72dbb7a561f913740.docx"},{"id":96090978,"identity":"470b66c4-4e7c-4f33-b52f-74f96c13a2ca","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":27594,"visible":true,"origin":"","legend":"","description":"","filename":"Tables.docx","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/0e9957903c31df2d029d5c73.docx"},{"id":96247855,"identity":"72912466-b0e7-4083-b97e-3abbe138c32d","added_by":"auto","created_at":"2025-11-19 07:27:46","extension":"json","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":8078,"visible":true,"origin":"","legend":"","description":"","filename":"7bc07dd267804149961e4edfdc78b4ce.json","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/f8912b08c18983a9545f1937.json"},{"id":96090985,"identity":"6302e600-28ad-42cd-9f90-54edda5fd5ca","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"xml","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":204688,"visible":true,"origin":"","legend":"","description":"","filename":"7bc07dd267804149961e4edfdc78b4ce1enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/116d5a744e62a458a309d3d8.xml"},{"id":96090981,"identity":"e032cec5-466d-474f-adc6-9451f7c32e4f","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"png","order_by":5,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":4000,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/56ff35c5c68880f16e559ea6.png"},{"id":96249873,"identity":"dafcb78c-acc7-4b0a-b5a4-76461a736901","added_by":"auto","created_at":"2025-11-19 07:36:33","extension":"png","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":12306,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/02c2540981a43dae7d82c836.png"},{"id":96090984,"identity":"970a75ce-5046-455e-b0ce-ce4fc3b38848","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"png","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":8881,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/2d38b10c7978b693c3d71cc4.png"},{"id":96246750,"identity":"104f58c6-1a22-4db5-a9a4-aff894d40954","added_by":"auto","created_at":"2025-11-19 07:26:37","extension":"jpeg","order_by":8,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":936124,"visible":true,"origin":"","legend":"","description":"","filename":"floatimage4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/bf8dea22ce2ce9ce338b4c38.jpeg"},{"id":96248661,"identity":"445d2787-57c5-4426-88bd-c67ce3f573d5","added_by":"auto","created_at":"2025-11-19 07:28:55","extension":"png","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":2478,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/e8eb14a8ee3d457cceb742bf.png"},{"id":96248725,"identity":"81de962a-2cd0-485f-bd29-db0561eb3cfa","added_by":"auto","created_at":"2025-11-19 07:29:04","extension":"png","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":6109,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/d902f5126f7d888e2da0bc3d.png"},{"id":96090987,"identity":"f6f7e79a-fa90-45de-b5b3-d691cebb59b1","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"png","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":4230,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/93bc6a408ab70294017c69d4.png"},{"id":96090989,"identity":"70a100e8-f45f-47ce-bc2b-bc639dc0842e","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"png","order_by":12,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":277379,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/73075805bdc5adaedbb354cc.png"},{"id":96249902,"identity":"b1a4ed10-e1ea-420d-a1e9-3c8146564168","added_by":"auto","created_at":"2025-11-19 07:36:42","extension":"xml","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":201253,"visible":true,"origin":"","legend":"","description":"","filename":"7bc07dd267804149961e4edfdc78b4ce1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/2fea86b008220ad72d73074f.xml"},{"id":96090990,"identity":"6e2cad3f-27a3-4635-b72f-f58e32dbb063","added_by":"auto","created_at":"2025-11-17 13:32:01","extension":"html","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":218618,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1/38eb30006280657b1842d17f.html"},{"id":108182525,"identity":"e52c2951-202d-4656-b096-0a04ee5c9a6b","added_by":"auto","created_at":"2026-04-30 08:59:24","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":568339,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8005446/v1_covered_f3cdf6e6-6dc3-4792-951c-277cf1958e59.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effect of Organic and Nano Selenium Dietary Supplementation on Growth, Survival, Feed Utilization, Gastrointestinal Health, and GPx Enzyme Activity of Gilthead Sea Bream (Sparus aurata) Larvae","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8005446/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8005446/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn this study, gilthead sea bream (G. Sea bream) larvae were fed three different micro diets (MD) during the weaning period, each containing 51.7% crude protein. The diets included: an MD supplemented with 4 mg of organic selenium per kilogram (Org-Se), an MD supplemented with 0.3 mg of nano-selenium per kilogram (Nano-Se), and a control MD without Selenium supplementation (C). The hatched larvae were fed live food (microgreen algae, rotifers, and Artemia) in addition to the MD. Using nine 5 m\u0026sup3; fiberglass tanks under a greenhouse, the experiment began with G. Sea bream larvae at 20 days post-hatch (DPH) and continued until the end of the trial at 60 DPH. The brood fish from which the larvae were derived received the same Selenium forms and doses in their basal diets, which consisted of a mix of 45% protein dry feed, squid, and sardines. Data on the broodstock and their offspring were reported in a separate research paper. The larvae, initially weighing 2.4 mg and measuring 4.5 mm in length, were replicated three times across the three treatments, with 50,000 larvae per tank (4 m\u003csup\u003e3\u003c/sup\u003e of seawater). The larvae fed the Nano-Se diet exhibited a higher survival rate of 57.43%, compared to 54.76% for those on the Org-Se diet and 53.73% for the control diet (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). The Nano-Se diet also produced the highest growth indices (FBW, SGR, FTL, and condition factor, K) and surpassed both the control and Org-Se diets. However, differences among the three treatments were not significant for FCR and PER (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). The study showed that the GPx enzyme activity in 20 DPH larvae from broodstock fed the Nano-Se diet was 10.34 U/mg of protein, significantly higher than that of larvae fed the Org-Se diet (9.36 U/mg of protein) and the control diet (8.81 U/mg of protein) (P\u0026thinsp;\u0026le;\u0026thinsp;0.05). Additionally, after 60 DPH, the larvae on the Nano-Se diet exhibited the highest GPx enzyme activity at 17.6 U/mg of protein, followed by the Org-Se at 15.54 U/mg of protein and the control diet at 13.33 U/mg of protein (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01).\u003c/p\u003e","manuscriptTitle":"Effect of Organic and Nano Selenium Dietary Supplementation on Growth, Survival, Feed Utilization, Gastrointestinal Health, and GPx Enzyme Activity of Gilthead Sea Bream (Sparus aurata) Larvae","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-17 13:31:56","doi":"10.21203/rs.3.rs-8005446/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"557bac32-6937-43f5-8a5e-335121484f1f","owner":[],"postedDate":"November 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":58062606,"name":"Biological sciences/Biochemistry"},{"id":58062607,"name":"Biological sciences/Ecology"},{"id":58062608,"name":"Earth and environmental sciences/Ecology"},{"id":58062609,"name":"Earth and environmental sciences/Environmental sciences"},{"id":58062610,"name":"Earth and environmental sciences/Ocean sciences"},{"id":58062611,"name":"Biological sciences/Zoology"}],"tags":[],"updatedAt":"2026-04-29T15:25:17+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-17 13:31:56","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8005446","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8005446","identity":"rs-8005446","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}