Fish Physiology and Biochemistry最新文献

{"title":"All that glitters is not gold: towards the standardization of experimental trials assessing functional feeds with immunomodulatory properties.","authors":"Enric Gisbert, Dolors Furones, Silvia Torrecillas","doi":"10.1007/s10695-025-01585-w","DOIUrl":"https://doi.org/10.1007/s10695-025-01585-w","url":null,"abstract":"<p><p>Functional feeds designed to enhance the host's immune response and improve disease resistance are among the most popular strategies to mitigate the impact of infectious diseases and abiotic stressors in aquaculture. While reviewing the current scientific literature on this issue, we have detected that there is a need to standardize the evaluation criteria for feed additives with immunostimulant properties in terms of the duration of the trial and selection of key end-points related to the expected effect of the dietary intervention. The evaluation of the disease protective role of a feed additive should not be based only on end-points from cellular and immune biomarkers, but it should also be complemented with end-points based on survival data of specimens exposed to an in vivo infective challenge. We also recommend giving special consideration to the basal diet used in these studies since the inclusion of certain ingredients may have confounding results with those expected from the additive or functional ingredient of interest. Regardless of the in vivo challenge model selected (balneation, cohabitation, intraperitoneal injection, or oral/anal intubation), abiotic factors such as temperature, water flow, light, and water quality strongly influence the development of disease and must be also taken into consideration when designing experimental challenge models. Thus, it is of paramount importance to standardize the studies testing the efficacy of functional diets designed to protect the host from infectious agents and to assist in harmonizing the interpretation of their results.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"173"},"PeriodicalIF":2.5,"publicationDate":"2025-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145291652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of inclusion level of protein in larval diet of Labeo rohita (Hamilton, 1822) during early ontogeny.","authors":"Mashooq Ali, Amina Zuberi, Faisal Ahmad Lodhi, Fida Ullah Khan, Wahag Ellahi","doi":"10.1007/s10695-025-01589-6","DOIUrl":"https://doi.org/10.1007/s10695-025-01589-6","url":null,"abstract":"<p><p>Optimization of larval feed is a prerequisite for the successful ontogeny of fish larvae. A feeding trial of 35 days was conducted in a replica of five (500 larvae per tank/2500 per group), to determine the dietary protein requirements of rohu Labeo rohita larvae. Four experimental nano-particulate diets (P45, P50, P55, P60) having 45, 50, 55, and 60% CP were prepared and fed to L. rohita larvae from 3 to 35 DAH (days after hatching). Sampling for growth assessment, digestive enzymes, and gene expression study was done on 3, 10, 15, 20, 25, 30, and 35 DAH. Among all the diets, P55 followed by P60 showed the most significant positive effect on growth (NWG, SGR) and survival of fish larvae. Amylase did not show any significant change among the experimental groups; however, total protease, trypsin, and chymotrypsin showed significantly high activity in P55, followed by P60, and the least activity in P45. Moreover, a positive correlation was observed between age DAH and GH and IGF-1 in all groups, while a negative correlation was observed with myogenic-regulating factors MRFs, i.e., MyoD and MYF-5. The significantly higher expression of GH and IGF-1, and a sustained higher expression of MRFs in P55 among all the studied groups, indicate 55%CP as the optimum dietary protein requirement for L. rohita larvae.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"172"},"PeriodicalIF":2.5,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145250678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the immunomodulatory and haemato-protective roles of curry leaf ethanolic extract (Murraya koenigii) in Labeo rohita fingerlings Infected with Aeromonas hydrophila.","authors":"Sourabh Debbarma, Bagthasingh Chrisolite, Panchavarnam Sivasankar, P Senthil Kumar, V Senthil Kumar, N Daniel, Palaniappan Subash, Muthumariappan Selvamagheswaran, Mohamed Mansoor, Magesh Kumar Paulraj","doi":"10.1007/s10695-025-01586-9","DOIUrl":"https://doi.org/10.1007/s10695-025-01586-9","url":null,"abstract":"<p><p>Aeromonas hydrophila is a highly virulent pathogen that causes substantial mortality in Labeo rohita fingerlings. In our present study, phytochemical analysis of curry leaf (Murraya koenigii) confirmed the presence of bioactive compounds such as alkaloids, phenolics, flavonoids, and terpenoids, known for their potent antimicrobial and immunomodulatory properties. This study evaluates the immunomodulatory and haemato-protective effects of curry leaf (Murraya koenigii) ethanolic extract (CLEE) against Aeromonas hydrophila infection in Labeo rohita, focusing on haematological, biochemical, and immunological parameters. In infection trials, survival rates were higher for feeds treated with 1 g, 2 g, and 3 g of CLEE were 46.67%, 68.89%, and 66.67%, respectively, compared to 36.67% in the bacterial control group. Haematological results showed a significant dose-dependent increase in red blood cell (RBC) count, haemoglobin, and white blood cell (WBC) count. The CLEE 2 g and CLEE 3 g groups had significantly (P < 0.05) higher RBC counts of 1.08 ± 0.01^a × 10¹²/L and 0.99 ± 0.07^a × 10¹²/L, compared to 0.49 ± 0.09^c × 10¹²/L in the bacterial control. Biochemical analysis revealed significant (P < 0.05) reductions in serum glucose, total protein, and liver enzymes (SGOT, SGPT, ALP). Specifically, serum glucose levels significantly (P < 0.05) decreased from 99.93 ± 3.04^a mg/dL in the bacterial control to 75.52 ± 1.68^d mg/dL in the CLEE 2 g and 79.89 ± 1.86^c mg/dL in the CLEE 3 g. Antioxidant enzyme activities, including superoxide dismutase (SOD), catalase, and myeloperoxidase activity (MPO), were significantly (P < 0.05) higher in CLEE-treated groups. Histopathological analysis showed partial regeneration of liver and kidney tissues, especially in the CLEE 2 g and CLEE 3 g groups. These findings suggest that CLEE effectively mitigates A. hydrophila infection, improves immune function, reduces oxidative stress, and promotes tissue recovery in L. rohita fingerlings. This study addresses a significant research gap, offering insights into CLEE's potential applications in aquaculture and its therapeutic efficacy in combating bacterial infections.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"171"},"PeriodicalIF":2.5,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145212137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of vitamins in fish farming: growth performance, immunity, disease resistance, and body composition.","authors":"Mohammad Hossein Khanjani, Gholamreza Ghaedi, Moslem Sharifinia","doi":"10.1007/s10695-025-01579-8","DOIUrl":"https://doi.org/10.1007/s10695-025-01579-8","url":null,"abstract":"<p><p>Aquaculture is a crucial sector in the global food system, significantly contributing to the supply of nutritious food and creating economic opportunities. This review article examines the essential role of vitamins in fish farming, highlighting their contributions to growth performance, immune function, antioxidant activity, digestive efficiency, disease resistance, and overall body composition. Vitamins are not only vital nutrients for the growth and metabolic functions of aquatic organisms but also serve as essential cofactors in numerous biochemical reactions, thereby promoting fish health and development. Recent innovations in aquafeed formulations and vitamin nutrition have led to a reassessment of the dietary vitamin needs for various farmed fish species. This review synthesizes contemporary research in fish nutrition, demonstrating the substantial effects of vitamins on growth rates (up to 20%), immune response enhancement (up to 40%), optimization of digestive and hepatic enzyme activities, and improvement of biochemical and hematological parameters. The magnitude of these benefits is influenced by factors such as vitamin type, fish species, age, and environmental conditions. Additionally, the review highlights the significance of vitamins in enhancing disease resistance and improving body composition in aquaculture species. The insights provided aim to guide aquaculture professionals and researchers in recognizing the critical role of vitamins in fostering sustainable fish farming practices. Future research in fish nutrition should prioritize the development of sustainable vitamin supplementation strategies, including the exploration of plant-based and microbial vitamin sources, the optimization of nutrient delivery methods, and the reduction of environmental impacts. By focusing on these areas, we can enhance fish health, improve feed efficiency, and promote more environmentally sustainable aquaculture practices.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"170"},"PeriodicalIF":2.5,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145205904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dietary tryptophan requirements and deficiency effects of olive flounder Paralichthys olivaceus at low water temperatures.","authors":"Jaehyeong Shin, Suhyeok Kim, Yeonji Lee, Yein Lee, Wonhoon Kim, Sanghyun Song, Sua Kim, Kyeong-Jun Lee","doi":"10.1007/s10695-025-01584-x","DOIUrl":"https://doi.org/10.1007/s10695-025-01584-x","url":null,"abstract":"<p><p>The olive flounder (Paralichthys olivaceus) is an economically important species in South Korea. However, the specific dietary requirement for tryptophan (Trp) has not been determined for this species at any growth stage. Thus, this study aimed to determine the dietary Trp requirement for juvenile olive flounder under low water temperature conditions. Two consecutive feeding trials were conducted, each using diets with different concentrations of dietary Trp: Exp-Ⅰ (0.39-14.46 g kg^-1) and Exp-Ⅱ (0.93-6.96 g kg^-1). The initial mean body weights of the olive flounder were 4.38 ± 0.03 g (Exp-Ⅰ) and 18.4 ± 0.1 g (Exp-Ⅱ). In Exp-Ⅰ and Exp-Ⅱ, fish were randomly distributed into 18 tanks (120 L), corresponding to six dietary groups with three replicates per group (30 fish per tank). Fish were fed the experimental diets for 13 weeks (Exp-Ⅰ) and 8 weeks (Exp-Ⅱ). The water temperatures during the trials were 18.2 ± 2.4 ℃ in Exp-Ⅰ and 17.5 ± 2.8 ℃ in Exp-Ⅱ, representing suboptimal thermal conditions. The results indicate dietary Trp concentration significantly affected the growth and survival of the fish. In particular, the lowest growth and survival were observed in fish fed the diet with the lowest concentration of Trp in both feeding trials. Additionally, the fish fed the Trp-deficient diet (0.39 g kg^-1) exhibited lower levels of hematological parameters, immunity, antioxidant capacity and whole-body crude protein compared to Trp supplemented groups (2.33-14.46 g kg^-1). In fish fed a Trp-deficient diet (0.39 g kg^-1), expression of tight junction proteins was down-regulated, abnormal development of mucosal folds was observed, and intestinal inflammatory cytokines were upregulated compared to Trp supplemented groups (2.33-14.46 g kg^-1). Fish fed Trp-supplemented diets showed significantly higher plasma levels of Trp, serotonin, melatonin and cortisol compared to those fed the Trp-deficient diet. The dietary Trp concentration required for fish growth was estimated to be 3.08 g kg^-1 (6.06 g kg^-1 of protein) in the juvenile stage (Exp-Ⅰ) and 2.17 g kg^-1 (4.27 g kg^-1 of protein) in the post-juvenile stage (Exp-Ⅱ), respectively, as determined by broken-line regression based on final body weight.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"169"},"PeriodicalIF":2.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145174440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential toxicological assessment of 4-Methylimidazole (4-MEI) in Ctenopharyngodon idella; LC₅₀ determination, acute and sublethal effects on physiological, immunological, and histopathological indicators.","authors":"Muhib Zaman, Amina Zuberi, Waqar Younas, Muhammad Noorullah, Faisal Ahmad Lodhi, Adnan Khan","doi":"10.1007/s10695-025-01578-9","DOIUrl":"https://doi.org/10.1007/s10695-025-01578-9","url":null,"abstract":"<p><p>4-Methylimidazole (4-MEI) is a widely used industrial compound and a common byproduct of caramelization in various foods and beverages. It enters aquatic ecosystems through multiple ways and is a well-recognized toxic and potentially carcinogenic substance in humans. In this study, the median lethal concentration (LC₅₀) of 4-MEI for Ctenopharyngodon idella over 96 h was determined for the first time in fish and found to be 26.79 mg/L. Subsequently, to assess its toxicological impact, C. idella fingerlings were exposed to an acute concentration (LC₅₀ for 96 h) and two sublethal concentrations, 1/5th (5.35 mg/L) and 1/10th (2.69 mg/L) of the LC₅₀, over 35 days. Acute exposure resulted in significant adverse effects, including substantial increases in white blood cell count, total immunoglobulins, lysozyme activity, phagocytic activity, respiratory burst, and the enzymatic activities of AST, ALT, ALP, and LDH. There was also upregulation of key immune-related genes: TNF-α, Interleukin-1β, Lysozyme-C, and Lysozyme-G. In contrast, red blood cell count, hemoglobin levels, hematocrit, total protein, albumin, globulin, and the albumin-to-globulin ratio were significantly reduced. Sublethal exposures produced concentration-dependent toxic effects. Histological analysis revealed that fish exposed to acute concentration exhibited marked structural alterations (> 50%) in liver and gill tissues. However, the sublethal concentration exposure (1/5th and 1/10th of LC₅₀) induced moderate (< 50%) to mild (< 10%) histopathological changes, respectively. These findings demonstrate the toxic effects of 4-MEI on fish and highlight the urgent need for increased awareness regarding its environmental risks and impact on aquatic life.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"168"},"PeriodicalIF":2.5,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145174457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unravelling the hsp70 gene in snubnose pompano (Trachinotus blochii): insights into stress response mechanisms.","authors":"Gayathri Suresh, Sumithra Thangalazhy Gopakumar, Krupesha Sharma S R, Ambarish Purackattu Gop, Vishnu Suresh Govind, Anusree Velappan Nair, Amritha Jagannivasan, George Joseph Chakkalakkal, Sudarsan Kalappurakal Santhoshkumar, Gopalakrishnan Achamveetil","doi":"10.1007/s10695-025-01582-z","DOIUrl":"https://doi.org/10.1007/s10695-025-01582-z","url":null,"abstract":"<p><p>Heat shock proteins (HSPs) are molecular chaperones that play a crucial role in fish physiology from stress-induced damage by stabilizing proteins and enhancing survival under environmental challenges. This study characterizes the stress-responsive hsp70 (tb-ihsp70) gene in Trachinotus blochii, a prime marine aquaculture species, from an evolutionary perspective and links its expression to salinity and pathogen stress. The tb-ihsp70 encodes a 639 amino acid protein with conserved ATPase and substrate-binding domains critical for protein conformation under stress. Phylogenetic analysis grouped it within Carangidae, showing a strong link to Trachinotus ovatus, with marine and freshwater species forming distinct clades, reflecting the environmental role in its phylogeny. Structural modelling revealed a Y-shaped conformation with high-confidence validation scores. STRING analysis identified functional partners, highlighting involvement in broader stress response pathways. The intronless feature and expression profiling classified tb-ihsp70 as a constitutively expressed and moderately inducible HSP70. Expression in healthy fish was maximum in gill > posterior kidney > spleen > liver > heart. Salinity stress showed significant upregulation at 3‰ on day two (7.95-fold) and three (5.26-fold), while no significant changes were observed at 42‰ on any day, indicating a stronger and longer tb-ihsp70 induction at lower salinity levels. Vibrio harveyi challenge peaked expression at 12 h in spleen (73.86-fold), heart (40.88-fold), and posterior kidney (23.10-fold). In conclusion, this first comprehensive characterization underscores the role of tb-ihsp70 in biotic and abiotic stress adaptation, supporting its potential as a molecular biomarker for T. blochii health research in mariculture.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"167"},"PeriodicalIF":2.5,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145124641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diet shifts alter the activity and distribution of digestive enzymes in an herbivorous fish.","authors":"K Clerre Rafanan, Michelle J Herrera, Caitlyn Catabay, Donovan P German","doi":"10.1007/s10695-025-01567-y","DOIUrl":"10.1007/s10695-025-01567-y","url":null,"abstract":"<p><p>Digestion is primarily performed by digestive enzymes. Here, we examined the activity levels of seven digestive enzymes along the digestive tract of the herbivorous fish, Cebidichthys violaceus. We reared C. violaceus on carnivore, omnivore, and herbivore diets in the laboratory for nine months and compared the digestive enzyme activities among the fish on the different diets and with wild-caught fish consuming their natural foods. Enzymatic activities were generally lower in the laboratory than in wild-caught fish. The marked anterior-to-posterior amylase activity gradient along the gut in wild-caught fish was absent in the lab-fed fish. We hypothesize that the dampened enzymatic activity may have been caused by reduced food intake in the laboratory in comparison to the wild fish. N-acetyl-β-D-glucosaminidase (NAGase) activity (degrades chitin breakdown products) peaked in the distal intestines of the lab-fed fish, but not the wild fish. The role of this enzyme in the digestive process remains unknown since the lab diets contained no chitin, and its origin may have been microbial. Overall, C. violaceus can tolerate diets with a wide range of protein and carbohydrate levels. However, the totality of our data suggests that live algal diets may be best for this herbivorous fish in a captive setting, especially for aquaculture.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"166"},"PeriodicalIF":2.5,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12446097/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145080047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Salinity-dependent responses differentiate branchial ion regulation during acute hypothermal stress in euryhaline Indian Medaka.","authors":"Naveen Ranasinghe, Salman Akram, Shi-Shien Lee, Pin-Jhu Liao, Tsung-Jui Yang, Yu-Chieh Kung, Tsung-Han Lee, Chia-Jui Liu","doi":"10.1007/s10695-025-01565-0","DOIUrl":"https://doi.org/10.1007/s10695-025-01565-0","url":null,"abstract":"<p><p>Gill function in gas exchange and ion regulation is crucial for ionoregulatory homeostasis in teleost fishes, yet further research is needed to elucidate how cold stress affects these processes, particularly in relation to salinity-dependent tolerability. Indian medaka (Oryzias melastigma) were acclimated to freshwater (FW) and seawater (SW) environments before being exposed to cold stress at 18 °C for 168 h. The protein abundance of the apoptotic marker Caspase-3 increased significantly in SW-acclimated fish compared to controls, indicating a heightened apoptotic response under cold stress in SW conditions. Concurrently, the expression of the anti-apoptotic gene birc5 exhibited distinct patterns in FW and SW, suggesting differential regulatory mechanisms in response to cold exposure. Transcriptomic analysis revealed that cold stress significantly influenced genes related to ion regulation, osmoregulation, and cellular metabolism, with distinct pathways activated in FW and SW environments. Notably, SW-specific genes were predominantly involved in metabolic pathways and stress signaling, while FW-specific genes were linked to transport processes and cellular maintenance. Additionally, cold stress significantly affected the expression of Na⁺/K⁺-ATPase (NKA) subunits and ion transport genes, underscoring the impact of temperature and salinity on gill function. The study highlights the importance of tight junctions (TJ) and gap junction (GJ) in maintaining gill integrity during environmental stress, with differential regulation of key genes like ocln, cask, and gja3 in response to salinity and temperature shifts. These findings highlight the superior molecular and cellular adaptations of euryhaline fish in SW to cold stress, emphasizing how salinity enhances gill responses and suggesting potential strategies for improving cold tolerance in aquaculture.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"165"},"PeriodicalIF":2.5,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145074334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tissue-specific effects of stocking density on fatty acid composition and liver metabolism in rainbow trout (Oncorhynchus mykiss).","authors":"Zhao Li, Kang Dong, Yuling Xu, Yaxin Wang, Zhishuai Hou, Qinfeng Gao, Shuanglin Dong","doi":"10.1007/s10695-025-01555-2","DOIUrl":"10.1007/s10695-025-01555-2","url":null,"abstract":"<p><p>Rainbow trout (Oncorhynchus mykiss), which is rich in high-quality protein and polyunsaturated fatty acids (PUFAs), is one of the most commercially important aquaculture species worldwide. The fatty acid profiles of trout, however, might be substantially influenced by different stocking densities. The present study aims to evaluate the effects of stocking density on the fatty acid composition and hepatic metabolomics of rainbow trout. Juvenile rainbow trout were reared for 84 days in circular tanks at 3 distinct levels of stocking density, i.e., low (group LD, 9.15 g/L), moderate (group MD, 13.65 g/L), and high (group HD, 27.31 g/L). The results showed that the levels of C22:6 n-3 (Docosahexaenoic acid, DHA) and total n-3 PUFAs in the dorsal muscles of the fish at group MD were significantly higher than those at groups LD and HD (p < 0.05). For ventral muscles, fish at group HD showed significantly decreased content of C16:1n-9 (palmitoleic acid) and n-3 PUFAs compared to those at groups LD and MD (p < 0.05). Hepatic fatty acid profiles showed significant reductions in monounsaturated fatty acids (MUFAs) for the fish at groups MD and HD compared to those at group LD (p < 0.05). Moreover, the concentrations of total n-6 PUFAs in the dorsal muscle were positively correlated with stocking density (R = 0.7357, p = 0.0238), while the levels of total n-3 PUFAs in the ventral muscle (R =  - 0.8478, p = 0.0039) and the levels of total MUFAs in the liver (R =  - 0.7837, p = 0.0101) showed negative correlations to the fish stocking densities. Metabolomics analyses further revealed that stocking density influenced the pathways related to glycerophospholipid metabolism, fatty acid degradation, and arachidonic acid metabolism. The results suggested that high stocking density altered fatty acid profiles and enhanced antioxidant and inflammatory responses in rainbow trout, providing valuable insights for optimizing aquaculture practices to improve the nutritional quality of farmed trout.</p>","PeriodicalId":12274,"journal":{"name":"Fish Physiology and Biochemistry","volume":"51 5","pages":"164"},"PeriodicalIF":2.5,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145052596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}