{"topic_id":"evidence_exotic_fish_nutrition","category":"evidence","context":"---\ntopic_id: evidence_exotic_fish_nutrition\ncategory: evidence\ntitle: \"Evidence cluster — Aquarium fish (teleost fish) nutrition (peer-reviewed, Europe PMC)\"\nlang: en\nsource: \"Europe PMC (Europe PubMed Central) REST search, first-hand peer-reviewed abstracts, pulled 2026-08-01\"\nsource_file: pdf-raw/evidence/europepmc_fish_nutrition_2026-08-01.txt\ndate_parsed: 2026-08-01\ntokens_estimated: 5058\nverification:\n  method: paraphrase\n  claims: 12\n  passed: 12\n  date: 2026-08-01\nsource_document: \"Peer-reviewed Aquarium fish nutrition literature (Europe PMC, first-hand abstracts)\"\ncitation:\n  authority: \"Europe PMC\"\n  title: \"Evidence cluster — Aquarium fish (teleost fish) nutrition (peer-reviewed, Europe PMC)\"\n  url: \"https://www.ebi.ac.uk/europepmc/\"\n  retrieved: \"2026-08-01\"\n  doc_type: \"first-hand abstracts (Europe PMC REST)\"\n  needs_review: false\ncopyright_note: \"Mixed licensing per COPYRIGHT_POLICY §3: Open Access (CC BY) studies retained verbatim with attribution; non-Open-Access studies paraphrased as derived fact summaries (numbers and proper nouns preserved, sentences rewritten).\"\nlicense: mixed\nauthority_tier: T2\nauthority_tier_basis: \"T2:oa-repo\"\nauthority_tier_date: 2026-08-04\n---\n\n# Evidence: Aquarium fish (teleost fish) nutrition\n\nSource: Europe PMC (Europe PubMed Central) REST search — first-hand peer-reviewed abstract records, pulled 2026-08-01.\nQueries covered nutrient requirements, diet formulation, supplementation and deficiency for teleost fish.\nThe cluster returns **12** representative nutrition studies with abstracts below. Abstract text is verbatim from source; each study is traceable by PMID.\n\n## Studies\n- **PMID 41060374 (2026, Conservation biology : the journal of the Society for Conservation Biology)** — Extent of threats to marine fish from the online aquarium trade in the United States.. Abstract (opening): The global marine aquarium hobby is a multibillion-dollar industry, largely driven by demand from the United States. Much of this trade occurs online. We web scraped 4 major US-based e-commerce platforms selling marine aquarium fish to determine the retail price and source (wild capture, aquaculture, or both) of 13 families of ray-finned marine fish (Actinopterygii). We supplemented this with ecological and economic trait data from FishBase and the International Union for Conservation of Nature (IUCN). Across all platforms and 13 popular fish taxonomic families, we found 734 unique species for sale, 89.2% (655 species) of which were sourced exclusively from the wild. A total of 45 species were of conservation concern (20 threatened species and 25 additional species with decreasing population trends), 38 of which were sourced solely from the wild. Retail price was significantly correlated with source, body length, minimum occupied depth, and schooling behavior. A further 100 species for sale were not listed as being in the aquarium trade in FishBase or by the IUCN, indicating incomplete information on this fishery in 2 important databases. For 58 species (encompassing 71 variants) with both wild-caught and captive-bred individuals for sale, aquaculture fish were a mean 28.1% (95% confidence interval 15.3) cheaper than their wild-caught counterparts. *[CC BY — Open Access, verbatim with attribution.]*\n  Source: https://pubmed.ncbi.nlm.nih.gov/41060374/\n- **PMID 42116709 (2026, The Journal of experimental biology)** — Gut microbial composition varies with host metabolic phenotype in juvenile Atlantic salmon.. Abstract (opening): Standard metabolic rate (SMR) influences growth, behaviour and energy use in fish, yet its relationship with gut microbiota remains unclear. Here, we combined physiological measurements with 16S rRNA sequencing of foregut and hindgut tissue to test whether gut microbial communities differ with metabolic phenotype in juvenile Atlantic salmon. High-SMR fish showed greater growth efficiency and lower body water content than low-SMR fish, indicating higher fat levels. In contrast, microbial differences were most evident in the foregut, where low-SMR fish exhibited significantly higher alpha diversity. Microbial beta-diversity analyses revealed clear segregation among metabolic groups, and distance-based redundancy analysis showed that both SMR and body mass strongly explained variation in foregut microbial composition. Correlation analysis identified a negative association between SMR and members of the Rhodobacteraceae family, which were consistently more abundant in the foregut of low-SMR fish. Together, these findings indicate that the metabolic phenotype is associated with distinct patterns of energy utilisation and gut microbiota composition, suggesting that foregut microbial communities may contribute to individual differences in metabolic strategy. *[CC BY — Open Access, verbatim with attribution.]*\n  Source: https://pubmed.ncbi.nlm.nih.gov/42116709/\n- **PMID 42441052 (2026, Journal of veterinary research)** — *[Paraphrased derived summary — non-Open-Access source.]* In European sea bass (Dicentrarchus labrax), DNA sequencing of the leptin (lep) gene revealed twelve novel SNPs (including a non-synonymous exon-3 variant g.11004767C>T, arginine-to-tryptophan) associated with growth traits such as total and fillet weight and body length (p<0.05). Two haploblocks were found, with the GTA haplotype linked to the highest growth and AG carriers outperforming others (p<0.01); the SNPs may aid marker-assisted selection for growth in aquaculture.\n  Source: https://pubmed.ncbi.nlm.nih.gov/42441052/\n- **PMID 42106141 (2026, Molecular and cellular endocrinology)** — *[Paraphrased derived summary — non-Open-Access source.]* In goldfish (Carassius auratus), two melanocortin-4 receptor homologs (caMC4R and caMC4R-like) differ in their third intracellular loop and thus in cAMP signalling. Knockdown of either promoted appetite and growth, but caMC4R knockdown increased muscle lipid (via PDHB) whereas caMC4R-like knockdown increased hepatic lipid (via PPARgamma and SREBP-1c). The findings offer leads for enhancing growth and modulating body composition in cultured fish.\n  Source: https://pubmed.ncbi.nlm.nih.gov/42106141/\n- **PMID 42353504 (2026, Animals : an open access journal from MDPI)** — *[Paraphrased derived summary — non-Open-Access source.]* The hybrid golden pompano 'Chenhai No. 1' grows faster than its Trachinotus ovatus parent; integrated transcriptomic and metabolomic profiling of muscle identified 3,172 differentially expressed genes (notably a 'darkorange2' WGCNA module with upregulated mapk8a, acacb, and pkmb) and 576 altered metabolites enriched in glycolysis, the TCA cycle, amino-acid metabolism, lipid biosynthesis, and mTOR signalling. Coordinated gene-metabolite links indicate the growth advantage arises from synergistic energy, amino-acid-sensing, and lipid metabolic remodelling.\n  Source: https://pubmed.ncbi.nlm.nih.gov/42353504/\n- **PMID 42497081 (2026, FASEB journal : official publication of the Federation of American Societies for Experimental Biology)** — *[Paraphrased derived summary — non-Open-Access source.]* In a teleost model, a high-fat diet suppressed hepatic spermidine synthase (SRM) expression via XBP1, and SRM loss impaired insulin signalling (reduced AKT phosphorylation, increased gluconeogenic enzymes), while SRM overexpression improved sensitivity. The effect runs through its metabolite spermidine (SPD) acting via AMPK; the high-fat diet lowered hepatic SPD by 35% and the p-AKT/AKT ratio by 58% and raised blood glucose by 39%, whereas SPD supplementation raised p-AKT/AKT by 131% and lowered glucose by 20%. The authors identify the SRM-SPD axis as a link between nutritional stress and insulin resistance and suggest SPD as a nutraceutical.\n  Source: https://pubmed.ncbi.nlm.nih.gov/42497081/\n- **PMID 42119748 (2026, Fish & shellfish immunology)** — *[Paraphrased derived summary — non-Open-Access source.]* In grass carp (Ctenopharyngodon idella), CD4-1+ T cells were shown essential for vaccine-induced antibody production and antibacterial immunity against Aeromonas hydrophila. The inactivated vaccine induced IL-21 from these T cells, and IL-21 promoted B-cell differentiation into plasma cells and IgM secretion while acting as a molecular adjuvant; depleting CD4-1+ T cells lowered specific IgM and protection, and IL-21 injection only partially restored survival without recovering antibody levels.\n  Source: https://pubmed.ncbi.nlm.nih.gov/42119748/\n- **PMID 42235724 (2026, Fish & shellfish immunology)** — *[Paraphrased derived summary — non-Open-Access source.]* In zebrafish (Danio rerio), the G protein-coupled receptor 119 (GPR119) was cloned and shown to suppress pro-inflammatory cytokines in hepatocytes when activated by the agonist MBX-2982, an effect confirmed by gain- and loss-of-function studies under palmitic-acid and lipopolysaccharide challenge. Mechanistically, GPR119 engages Gs/Gq signalling to raise cAMP-CREB activity and inhibit NF-kappaB p65 phosphorylation, with beta-arrestin-ERK signalling fine-tuning the response; the authors propose GPR119 as a therapeutic target for liver health in farmed fish.\n  Source: https://pubmed.ncbi.nlm.nih.gov/42235724/\n- **PMID 42019591 (2026, Fish & shellfish immunology)** — *[Paraphrased derived summary — non-Open-Access source.]* In largemouth bass (Micropterus salmoides), an intraperitoneal largemouth bass virus (LMBV) infection model showed robust gut innate and adaptive immunity, with secondary infection producing a stronger IgM response (more IgM+ B cells and higher virus-specific IgM titres with likely neutralising activity). Intestinal IgM responses were segment-specific, with the hindgut markedly stronger than fore- and midgut, highlighting the hindgut's role in antiviral intestinal immunity and informing mucosal vaccine design.\n  Source: https://pubmed.ncbi.nlm.nih.gov/42019591/\n- **PMID 41628736 (2026, Fish & shellfish immunology)** — *[Paraphrased derived summary — non-Open-Access source.]* Two CCL20-like genes (PaCCL20l1 and PaCCL20l2) were identified in ayu (Plecoglossus altivelis) and upregulated in multiple tissues after Vibrio anguillarum infection. Their recombinant peptides were chemotactic and anti-apoptotic with differing cell specificities, and neutralising the receptor PaCCR6 abolished all effects, showing these chemokines modulate leukocyte recruitment and survival through the PaCCR6 pathway.\n  Source: https://pubmed.ncbi.nlm.nih.gov/41628736/\n- **PMID 41720367 (2026, Fish & shellfish immunology)** — *[Paraphrased derived summary — non-Open-Access source.]* Single-cell RNA sequencing of blood, liver, spleen, and head kidney in Chinese tongue sole (Cynoglossus semilaevis) revealed five transcriptionally distinct granulocyte subsets with tissue-specific distributions and a bifurcated developmental trajectory from a shared progenitor in the head kidney and spleen (driven by the cxcr2/cxcr4 axis). A conserved cd44b-mediated communication module was inferred. The atlas informs fish immunology and aquaculture disease control.\n  Source: https://pubmed.ncbi.nlm.nih.gov/41720367/\n- **PMID 42200157 (2026, Aquaculture nutrition)** — Dietary Substitution of Soybean Meal With &lt;i&gt;Phaeodactylum tricornutum&lt;/i&gt; Meal Improves Growth, Skin Pigmentation, Nutrient Retention, and Lipid Metabolism in Grass Carp (&lt;i&gt;Ctenopharyngodon idella&lt;/i&gt;).. Abstract (opening): The search for alternative protein sources to replace soybean meal (SBM) is crucial for the sustainable development of aquaculture. This study investigated the effects of dietary replacement of SBM with <i>Phaeodactylum tricornutum</i> meal (PTM) on grass carp (<i>Ctenopharyngodon idella</i>) (65.00 ± 0.60 g). Five isonitrogenous and isolipidic diets were formulated, in which PTM replaced 0%, 25%, 50%, 75%, and 100% of SBM protein (denoted as PT0 to PT4). Fish fed diets PT2-PT4 showed significant improvements in specific growth rate (SGR) compared to the PT0 group after the 56-day trial (<i>p</i> < 0.05). All PTM groups exhibited significantly higher feed efficiency (FE) (<i>p</i> < 0.05). Skin pigmentation was markedly improved, with significantly higher redness (<i>a</i> <sup>∗</sup>) and yellowness (<i>b</i> <sup>∗</sup>) values observed in fish fed PTM-containing diets. Muscle nutritional quality was enhanced, as evidenced by significantly higher levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the PT3 and PT4 groups (<i>p</i> < 0.05). Notably, nitrogen (N) and phosphorus (P) retention efficiencies were significantly elevated in the PT2-PT4 groups (<i>p</i> < 0.05), indicating reduced nutrient discharge into the environment. Moreover, whole-body lipid content decreased with increasing graded levels of PTM substitution, and plasma triglycerides (TGs) and cholesterol levels were significantly reduced in all PTM-supplemented groups. Mechanistically, dietary PTM supplementation upregulated hepatic mRNA expression of lipolytic genes (peroxisome proliferator-activated receptor alpha [<i>pparα</i>], carnitine palmitoyltransferase 1 [<i>cpt1</i>], hormone-sensitive lipase [<i>hsl</i>], and adipose TG lipase [<i>atgl</i>]) and downregulated lipogenic genes (fatty acid synthase [<i>fas</i>], acetyl-CoA carboxylase alpha [<i>acc</i>], stearoyl-CoA desaturase-1 [<i>scd1</i>], and diacylglycerol O-acyltransferase 1 [<i>dgat1</i>]), suggesting transcriptional regulation that enhances lipid catabolism and inhibits lipogenesis. In conclusion, PTM can effectively replace dietary SBM protein while simultaneously improving growth performance, skin quality, and nutrient utilization in grass carp and reducing potential environmental pollution. These findings confirm that PTM is capable of improving nutrient utilization and reducing N/P output. PTM therefore represents a promising alternative protein ingredient for developing eco-friendly aquafeeds. *[CC BY — Open Access, verbatim with attribution.]*\n  Source: https://pubmed.ncbi.nlm.nih.gov/42200157/\n\nSource text: `pdf-raw/evidence/europepmc_fish_nutrition_2026-08-01.txt` (Europe PMC first-hand abstracts, pulled 2026-08-01).\n\n## License & attribution\n\nMixed licensing per COPYRIGHT_POLICY §3: Open Access (CC BY / CC BY-NC /\nCC BY-NC-ND) studies are reproduced verbatim with attribution under their specific\nCC license; non-Open-Access studies are paraphrased as derived fact summaries\n(numbers and proper nouns preserved, sentences rewritten). Original records:\n- https://pubmed.ncbi.nlm.nih.gov/41060374/\n- https://pubmed.ncbi.nlm.nih.gov/41628736/\n- https://pubmed.ncbi.nlm.nih.gov/41720367/\n- https://pubmed.ncbi.nlm.nih.gov/42019591/\n- https://pubmed.ncbi.nlm.nih.gov/42106141/\n- https://pubmed.ncbi.nlm.nih.gov/42116709/\n- https://pubmed.ncbi.nlm.nih.gov/42119748/\n- https://pubmed.ncbi.nlm.nih.gov/42200157/\n- https://pubmed.ncbi.nlm.nih.gov/42235724/\n- https://pubmed.ncbi.nlm.nih.gov/42353504/\n- https://pubmed.ncbi.nlm.nih.gov/42441052/\n- https://pubmed.ncbi.nlm.nih.gov/42497081/\n","sources":["Europe PMC — Evidence cluster — Aquarium fish (teleost fish) nutrition (peer-reviewed, Europe PMC) (retrieved 2026-08-01)"],"source":{"authority":"Europe PMC","title":"Evidence cluster — Aquarium fish (teleost fish) nutrition (peer-reviewed, Europe PMC)","url":"https://pubmed.ncbi.nlm.nih.gov/41060374/","retrieved":"2026-08-01","ref":"PMID 41060374","doc_type":"official PDF","source_document":"Peer-reviewed Aquarium fish nutrition literature (Europe PMC, first-hand abstracts)","verification_file":"pdf-raw/evidence/europepmc_fish_nutrition_2026-08-01.txt"},"source_document":"Peer-reviewed Aquarium fish nutrition literature (Europe PMC, first-hand abstracts)","source_file":"pdf-raw/evidence/europepmc_fish_nutrition_2026-08-01.txt","trust":{"authority_tier":"T2","fidelity":"paraphrase","license":"mixed","display_grade":"B"},"tokens_estimated":600,"generated_at":null,"tip":"Use /api/v1/topics to discover more topics. /api/v1/nutrient for precise single-point queries. /api/v1/cross_compare for 2-3 standard comparisons."}