Aquaculture最新文献

{"title":"Functional characterization of CSAD and its genomic variations modulating taurine synthesis and heat adaptation between two congeneric oyster species","authors":"Meiqian Pang ,&nbsp;Haigang Qi ,&nbsp;Chaogang Wang ,&nbsp;Rihao Cong ,&nbsp;Mingyang Du ,&nbsp;Zhuxiang Jiang ,&nbsp;Min Wang ,&nbsp;Li Li ,&nbsp;Guofan Zhang","doi":"10.1016/j.aquaculture.2025.742933","DOIUrl":"10.1016/j.aquaculture.2025.742933","url":null,"abstract":"<div><div>Oysters are characterized by an extremely high taurine content, a feature that constitutes one of the key reasons for the nutritional and commercial value of these shellfish. Nevertheless, within these organisms, the functions of key metabolic genes and their regulatory mechanisms remain poorly understood. In the current study, we confirmed that cysteine sulfinic acid decarboxylase (CSAD) catalyzes taurine synthesis in two congeneric oyster species: the Pacific oyster <em>Crassostrea gigas</em> and the Portuguese oyster <em>Crassostrea angulata</em>. These oysters are notable for their high aquaculture yields and distinct thermal tolerance levels. <em>Csad</em> displayed distinct thermal response patterns in the two oyster species and significantly contributed to the enhancement of thermal tolerance. Three genomic variations in the <em>Csad</em> promoter region were identified. These variations enhanced the transcriptional activity by varying degrees under heat stress conditions, with the activity increasing from 2.52-fold to 3.19-fold, 2.81-fold and 4.30-fold respectively. Our findings establish Poly (ADP-ribose) polymerase 1 (PARP1) as a transcriptional coregulator mediating the species-divergent thermal response of <em>Csad</em>. This research fills a significant void in our understanding of the regulatory mechanisms of taurine metabolism in marine invertebrates and has the potential to lay a theoretical groundwork for the genetic improvement of oysters via molecular-based methodologies.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742933"},"PeriodicalIF":3.9,"publicationDate":"2025-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 effects of microalgal feed supplementation on growth and digestive function of Acipenser baerii and Sparus aurata","authors":"Jorge García-Márquez ,&nbsp;Alejandro Morcillo-Guillén ,&nbsp;Antonio J. Vizcaíno ,&nbsp;Alba Galafat ,&nbsp;María Isabel Sáez ,&nbsp;Tomás Francisco Martínez ,&nbsp;Luciano Foglio ,&nbsp;Lorenzo Proietti ,&nbsp;Tiziana Bongiorno ,&nbsp;Francisco Gabriel Acién ,&nbsp;Katia Parati ,&nbsp;Francisco Javier Alarcón-López","doi":"10.1016/j.aquaculture.2025.742920","DOIUrl":"10.1016/j.aquaculture.2025.742920","url":null,"abstract":"<div><div>This study aims to assess the potential use of microalgae, produced through a sustainable process, as protein and lipid source in practical diets for two commercially valuable fish species: Siberian sturgeon (<em>Acipenser baerii</em>) and gilthead seabream (<em>Sparus aurata</em>). To achieve this goal, the study evaluated different biomasses of <em>Microchloropsis gaditana,</em> cultivated on either conventional synthetic medium (MSM) or diluted pig manure (MPM), incorporated crude or hydrolysed into aquafeeds. Specifically, the impact on growth performance, digestive enzyme activity, and intestinal morphology was evaluated in both species. Regarding growth performance, no significant improvement was observed in sturgeon fed <em>M. gaditana</em>-supplemented diets. However, gilthead seabream significantly increased body weight except for the group fed diets elaborated with hydrolysed microalgae. Digestive enzyme activities were also modified by the use of algal biomass, with negative effects in Siberian sturgeon, whereas gilthead seabream proteolytic activities were enhanced, which evidenced a species-specific digestive response. Finally, morphological analyses of intestinal mucosa revealed that dietary inclusion of <em>M. gaditana</em> induced significant changes in both species. In Siberian sturgeon, the inclusion of microalgae reduced the total absorption surface, regardless of the growth medium used for producing the microalgae. Conversely, in gilthead seabream, dietary inclusion positively influenced intestinal morphology, increasing the intestinal fold diameter, enterocyte height, and microvilli length, indicating enhanced nutrient uptake capacity. In conclusion, these results evidenced the potential application of microalgae obtained from biorefinery as a protein and lipid source in practical diets for both fish species. However, the contrasting effects observed in both species bring to light the need for future works to assess the species-specific responses to dietary changes.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742920"},"PeriodicalIF":3.9,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exosomal miR-4171-x contributes to T helper II cell immune response by regulating the Gata-3 expression in flounder (Paralichthys olivaceus)","authors":"Xueyan Shi ,&nbsp;Lixia Jiang ,&nbsp;Heng Chi ,&nbsp;Roy Ambli Dalmo ,&nbsp;Xiaoqian Tang ,&nbsp;Jing Xing ,&nbsp;Xiuzhen Sheng ,&nbsp;Wenbin Zhan","doi":"10.1016/j.aquaculture.2025.742930","DOIUrl":"10.1016/j.aquaculture.2025.742930","url":null,"abstract":"<div><div>Exosomes are recognized for their function as facilitators of intercellular communication and regulators of immune responses. However, the specific contributions of exosomes to the host's immune response against pathogens, especially concerning T cell immunity, remain inadequately elucidated in teleost fish. This study characterized exosomal miRNAs from the peritoneal cavity of flounder (<em>Paralichthys olivaceus</em>) challenged with <em>Vibrio anguillarum</em>. Exosomes isolated from uninfected and <em>V. anguillarum</em>-challenged flounder exhibited typical cup-shaped morphology and size distribution, and were further confirmed by the expression of exosomal markers (Cd9, Cd81, and Tsg101). miRNA transcriptome sequencing revealed that the expression profiles of 69 exosomal miRNAs exhibited significant alterations when comparing the infected group to the control group. Specifically, 49 miRNAs were found to be significantly upregulated, while 20 miRNAs were significant downregulation. Furthermore, GO and KEGG enrichment analyses indicated that the predicted target genes of these significantly differentially expressed miRNAs were involved in various immune processes, including signaling pathways related to T cell immune response. Functional studies identified exosomal miR-4171-x as a critical regulator, which mechanistically targets <em>gata3—</em>the master transcriptional regulator of Th2 cell differentiation. These findings provided novel insights into host-pathogen interactions and may inform future strategies for improving disease resistance in aquaculture.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742930"},"PeriodicalIF":3.9,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144588175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of consumer perceptions of sustainable fishery products","authors":"G. Cantos,&nbsp;C. Fuentes,&nbsp;I. Fernández-Segovia,&nbsp;A. Fuentes","doi":"10.1016/j.aquaculture.2025.742926","DOIUrl":"10.1016/j.aquaculture.2025.742926","url":null,"abstract":"<div><div>Consumers' concern about the environmental impact has triggered the need for available information on aspects related to the sustainability of the food products. Companies show consumers their environmental commitment and sustainability through certifications and sustainability labels. The present study aims to: (i) evaluate the presence of sustainability labels on the aquaculture and wild-caught fish products commercialised in Spain; (ii) study consumers' knowledge of sustainability seals; (iii) analyse the main aspects that affect the purchase decisions of sustainable food products. The supply of fish and fishery products was determined by market research. A consumer opinion survey was performed to assess labelling relevance, knowledge about sustainability labels and purchasing preferences. In Spain, sustainability labels appear on more than one third of fish products, with large differences found between different retailers. More than half of the products sold in German discount stores featured some sustainability label, a figure three times higher than the rate of products found in the Spanish supermarkets. The consumer survey showed that most Spanish consumers do not regularly check labelling information related to the environment and animal welfare, and they are largely unaware of the meaning of sustainability labels. Nonetheless, the conjoint analysis showed that the presence of sustainability seals enhances fish product purchases, especially for aquaculture products. These results demonstrate that marine sustainability seals and certifications can be used by the fish industry to increase purchase intention and to revalorise their products. However, informing consumers about the meaning and importance of these certifications is still necessary.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742926"},"PeriodicalIF":3.9,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CLIP-AFIR: A Contrastive Language-Image Pretraining Model for Accurate Fish Individual Fine-grained Re-identification","authors":"Jianing Quan ,&nbsp;Can Wang ,&nbsp;Yunchen Tian","doi":"10.1016/j.aquaculture.2025.742885","DOIUrl":"10.1016/j.aquaculture.2025.742885","url":null,"abstract":"<div><div>Similar to identifying different human individuals, accurately determining ”who is who” is a critical component in intelligent aquaculture, with broad applications in disease analysis, growth monitoring, and other aspects. The accuracy of fish Re-Identification (ReID) has greatly improved currently, yet challenges remain in distinguishing the same species, such as low precision and ID switching. Inspired by the multimodal large models, we propose a Contrastive Language-Image Pretraining model for Accurate Fish Individual fine-grained Re-identification (CLIP-AFIR). Based on the cross-modal contrastive learning, a set of trainable text tokens is introduced to represent different individuals, combined with the proposed Prompt Learner Module (PLM). The text and image encoders are trained through the two-stage paradigm, which enhances the adaptability in fish recognition. To improve the ability to discriminate subtle individual differences, a lightweight Fine-grained Feature Enhancement Module (FFEM) is further designed. By using shifted windows with overlapping regions to compute mask self-attention on local areas of the image, it enables effective representation of fine-grained local variations. On the constructed grouper dataset, the proposed CLIP-AFIR shows a significant improvement in the evaluations. Applied to the non-continuous fish individual recognition task, CLIP-AFIR achieves an accuracy of 98.6%, surpassing the state-of-the-art by 5.4 points.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742885"},"PeriodicalIF":3.9,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144572278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of Aeromonas hydrophila PS-1 and GFP-labeled tracking of its infection in Pelodiscus sinensis","authors":"Fa Dai ,&nbsp;Siyu Chen ,&nbsp;Wei Sun ,&nbsp;Jiehao Xu ,&nbsp;Chutian Ge ,&nbsp;Xiaodong Zhang","doi":"10.1016/j.aquaculture.2025.742914","DOIUrl":"10.1016/j.aquaculture.2025.742914","url":null,"abstract":"<div><div>The Chinese soft-shelled turtle (<em>Pelodiscus sinensis</em>) is a crucial economically significant aquatic species, yet its aquaculture is severely impacted by disease-related challenges. Among these, <em>Aeromonas hydrophila</em> stands out as one of the most prevalent pathogenic bacteria, responsible for the highest diversity of disease manifestations and detection rates in farmed <em>P. sinensis</em>. In this study, a pathogenic strain <em>A. hydrophila</em> PS-1 from diseased <em>P. sinensis</em> was isolated and identified. A green fluorescent protein (GFP) labeled PS-1 (PS-1/GFP) was constructed with the pAPR-EGFP plasmid. The growth, motility, and pathogenicity of PS-1/GFP showed no difference from that of the wild type strain. After artificial infection, green fluorescence was only observed in the intestine and liver in a paraffin section at 72 h of infection, which indicated that PS-1 infection exhibited tissue specificity. Accordingly, the colonization sites of PS-1 in <em>P. sinensis</em> were intestine and liver, with bacterial loads reaching as high as 5 × 10⁹ CFU/g and 7 × 10⁸ CFU/g, respectively. Moreover, PS-1 could internalize into intestinal fibroblast-like cells and induce similar cell morphological changes akin to pyroptosis. This work established methodological tools and fundamental insights for investigating diseases in <em>P. sinensis</em>, and laid the groundwork for further elucidation of the pathogen-host interaction mechanisms between <em>A. hydrophila</em> and <em>P. sinensis</em>.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742914"},"PeriodicalIF":3.9,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144557222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physiological reactions of large yellow croaker (Larimichthys crocea) to sound stimulus at 500 Hz: Implications for marine management regarding low frequency continuous noise","authors":"Shiqi Song ,&nbsp;Xiujuan Shan ,&nbsp;Chengcheng Su ,&nbsp;Yongsong Zhao","doi":"10.1016/j.aquaculture.2025.742888","DOIUrl":"10.1016/j.aquaculture.2025.742888","url":null,"abstract":"<div><div>With increasing in human activities such as the operation of offshore wind farms and shipping, the impacts of anthropogenic low frequency continuous noise on marine organisms have garnered increasing attention. This study used the sound-sensitive large yellow croaker (<em>Larimichthys crocea</em>) to investigate the physiological effects of low frequency continuous noise. Fish were exposed to continuous underwater noise at sound pressure levels of 105 ± 5 dB, 125 ± 5 dB, and 145 ± 5 dB for 15 days, with an unexposed control group. Antioxidant enzyme activities in the liver were measured, and transcriptome sequencing was performed to screen for noise stress-related differentially expressed genes. Results showed that superoxide dismutase (SOD) activity peaked under low noise stress but decreased significantly under high noise stress. Glutathione peroxidase (GSH-Px) activity decreased initially and then increased, reaching the highest level under high noise stress. Catalase (CAT) activity was highest under medium noise stress and similar to the control under high noise stress. Transcriptome analysis revealed that noise stress altered gene expression in the brain and liver, with differentially expressed genes significantly enriched in pathways related to neural function, apoptosis, metabolism, immunity, and signal transduction. Key genes in glutamatergic and GABAergic synapse pathways were downregulated, while <em>caspase</em> family genes in apoptosis pathways were upregulated. Genes related to pancreatic secretion and fatty acid metabolism were downregulated, and those in complement and chemokine signaling pathways were altered. The study suggests that continuous exposure to underwater noise from human activities generates excessive reactive oxygen species in <em>L. crocea</em>, disrupting the normal function of the antioxidant enzyme system. High-intensity noise may exceed its antioxidant defense capacity and potentially lead to neurologic damage, accelerated apoptosis, metabolic disorders, and compromised immune function in L. <em>crocea</em>. These findings provide a basis for the impact assessment of anthropogenic low frequency continuous noise on fishery resources.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742888"},"PeriodicalIF":3.9,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic transmission, self-fertilization, apomixis and triploidy in mixed hybridizations of sugar kelp (Saccharina latissima)","authors":"S. Bråtelund ,&nbsp;T. Ruttink ,&nbsp;F. Goecke ,&nbsp;G. Klemetsdal ,&nbsp;S. Forbord ,&nbsp;J. Skjermo ,&nbsp;D. Aldridge ,&nbsp;A.R. Borrero-Santiago ,&nbsp;J. Ødegård ,&nbsp;J. Funderud ,&nbsp;Å. Ergon","doi":"10.1016/j.aquaculture.2025.742928","DOIUrl":"10.1016/j.aquaculture.2025.742928","url":null,"abstract":"<div><div>The kelp species <em>Saccharina latissima</em> is gaining attention due to the growing interest in kelp cultivation in Europe and North America. The current common practice of propagation is to generate seedlings through mixed hybridization of individuals collected from the wild. However, virtually nothing is known about rates of self-fertilization, apomixis, and unintended selection in this process. Moreover, efforts to develop genetic material suitable for cultivation remain limited. We conducted a selection experiment to test how mixed hybridization and selection could be used for initial breeding for large-size <em>S. latissima</em> sporophytes. We mixed spores from 159 wild sporophytes to produce an F1 generation. Approximately 800 offspring were phenotyped and genotyped using “genotyping by sequencing” (GBS). Then, 25 large-sized individuals were selected as parents for an F2_selected population, while 25 random individuals served as parents of an F2_control population. Approximately 800 individuals from F2_selected and 200 individuals from F2_control were phenotyped and genotyped. Parentage assignment revealed considerable variation in transmission between parents. Selfing rates exceeded expectations under random mating in F2_selected (0.10), and particularly in F2_control (0.73), where it led to high inbreeding levels (<em>F</em>_IS = 0.16) and contributed to reducing the expected heterozygosity from 0.20 to 0.18. In F1, 4 % of the sporophytes were apomictic, while in F2_selected and F2_control the fraction of apomictic sporophytes was 0 % and 1 %, respectively. Additionally, spontaneous triploid offspring were identified on the basis of GBS data at a rate of 0.3 %–0.6 %. We discuss implications of our results for practical propagation and breeding of <em>S. latissima</em>.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742928"},"PeriodicalIF":3.9,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel grass carp pathogen Citrobacter amalonaticus induces severe intestinal inflammation","authors":"Zhongyi Liu ,&nbsp;Lianzhen Xin ,&nbsp;Yayun Xu ,&nbsp;Xiaoyan Xu ,&nbsp;Yubang Shen ,&nbsp;Liang Jia ,&nbsp;Dan Xu ,&nbsp;Lang Gui","doi":"10.1016/j.aquaculture.2025.742913","DOIUrl":"10.1016/j.aquaculture.2025.742913","url":null,"abstract":"<div><div><em>Citrobacter amalonaticus</em> is widely recognized as a conditionally pathogenic bacterium, primarily associated with meningitis, brain abscesses and urinary tract infections in humans. To date, no documented cases of <em>C. amalonaticus</em> causing disease in fish have been reported. However, our recent study identified this bacterium as a novel pathogen responsible for over 50 % morbidity in grass carp (<em>Ctenopharyngodon idella</em>). Through comprehensive morphological analysis, biochemical phenotype identification and 16S rRNA gene sequencing, this pathogen was confirmed as <em>C. amalonaticus</em> (ca). The lethal dose, 50 % (LD₅₀) of ca in grass carp was determined to be 2.04 × 10⁵ CFU/mL. Infected fish exhibited symptoms consistent with naturally diseased individuals, including ulcerated and hemorrhagic skin, abdominal distension, hemorrhagic and swollen cloaca, and severe ascites. Histopathological examination revealed extensive damage to the intestine, liver, spleen, and kidney, with the intestines exhibiting particularly severe lesions. The health status of the fish was assessed through various parameters, including hematological indices, intestinal enzyme activity 72 h post-infection and expression levels of inflammation-related genes at multiple time points (0, 24, 48, 72, 96 hpi). Results indicated significant changes, including increased white blood cell count, reduced digestive enzyme activity (e.g., trypsin, TRY), elevated oxidative stress enzyme activity (e.g., catalase, CAT), and upregulation of inflammatory genes (e.g., <em>IL-8</em>). Drug sensitivity testing demonstrated that ca was highly susceptible to ciprofloxacin, ofloxacin and vancomycin. This study confirms the pathogenicity of ca in fish and represents the first identification of <em>C. amalonaticus</em> infection in grass carp, causing severe intestinal inflammation. These findings provide valuable data for the prevention and treatment of this disease.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"609 ","pages":"Article 742913"},"PeriodicalIF":3.9,"publicationDate":"2025-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144614670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Protective role of oligochitosan in intestinal homeostasis to Edwardsiella ictaluri in hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂)","authors":"Lixin Ma,&nbsp;Zhilong Chen,&nbsp;Zhuojin He,&nbsp;Xiaomin Zheng,&nbsp;Yutao Li,&nbsp;Cuiyun Zhou,&nbsp;Li Lin,&nbsp;Fei Shi","doi":"10.1016/j.aquaculture.2025.742923","DOIUrl":"10.1016/j.aquaculture.2025.742923","url":null,"abstract":"<div><h3>Background</h3><div><em>Edwardsiella ictaluri</em> is a major pathogen that causes severe infections in fish. Oligochitosan has antioxidant and antibacterial properties, and can also regulate the immune system and intestinal flora.</div></div><div><h3>Aims</h3><div>In this study, we investigated the mechanisms of <em>E. ictaluri</em> infection in hybrid grouper and evaluated the effects of oligochitosan supplementation on intestinal health, gut microbiota, and metabolism.</div></div><div><h3>Methods</h3><div>In this study, we employed a combination of histopathology, TdT-mediated dUTP nick end labeling (TUNEL), biochemical analysis, 16S rRNA sequencing, fluorescence in situ hybridization (FISH), transcriptomics, and metabolomics.</div></div><div><h3>Results</h3><div><em>E. ictaluri</em> infection significantly altered goblet cell counts (<em>P</em> &lt; 0.05), apoptosis rates (<em>P</em> &lt; 0.01), increased villus height (<em>P</em> &lt; 0.05), and reduced muscularis thickness (<em>P</em> &lt; 0.01). Oligochitosan intervention effectively restored intestinal structure. Compared to controls, <em>E. ictaluri</em> elevated intestinal superoxide dismutase (SOD) (<em>P</em> &lt; 0.05) and amylase (AMS) activities (<em>P</em> &lt; 0.01), while oligochitosan significantly decreased catalase (CAT) activity relative to infected fish (<em>P</em> &lt; 0.01). The infection also increased bacterial load and disrupted microbiota composition, whereas oligochitosan promoted beneficial genera, including <em>Faecalibaculum</em> and <em>Bacteroides</em>. FISH analysis confirmed increased bacterial colonization post-infection (<em>P</em> &lt; 0.01), which was alleviated by oligochitosan (<em>P</em> &lt; 0.01). Transcriptomics revealed that <em>E. ictaluri</em> altered genes involved in fat absorption and TNF signaling, effects mitigated by oligochitosan. Metabolomics showed infection suppressed D-amino acid, taurine, and hypotaurine metabolism, reducing amino acid levels, while oligochitosan reversed these trends. Multi-omics correlation analyses indicated that oligochitosan modulated intestinal amino acid metabolism by enhancing probiotic-associated pathways.</div></div><div><h3>Conclusion</h3><div>Collectively, oligochitosan can alleviate <em>E. ictaluri</em> induced by enhancing intestinal tissue integrity and antioxidant defense, maintaining intestinal flora balance, and regulating amino acid metabolism.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"610 ","pages":"Article 742923"},"PeriodicalIF":3.9,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144548366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}