Aquaculture最新文献

{"title":"Exposure to ambient UVB light influences the welfare, energy requirements, metabolism, and relevant molecular biology of the Himalayan fish Tor putitora: Investigating the hidden costs of sunlight in upland aquaculture","authors":"M. Junaid Sidiq ,&nbsp;Alexander Ciji ,&nbsp;Ananya Khatei ,&nbsp;C. Siva ,&nbsp;Narinder Kumar Chadha ,&nbsp;Paramita Banerjee Sawant ,&nbsp;Pramod Kumar Pandey ,&nbsp;M.S. Akhtar","doi":"10.1016/j.aquaculture.2025.742496","DOIUrl":"10.1016/j.aquaculture.2025.742496","url":null,"abstract":"<div><div>The present study used a mid-to-high altitude dwelling migratory fish, <em>Tor putitora</em>, as a model for studying the impact of ambient UVB on flourishing fish culture in the high-altitudinal areas of the Indian Himalayas. For this, two sets of the juveniles of <em>T. putitora</em> (22 ± 6.3 g) were exposed for 60 days to two ambient UVB levels- 1.0 and 1.5 W/m² (T1 and T2). The two levels corresponded to about 24.0 % and 36.0 % of the daily average UVB incidence of the peak noon hours (1100 to 1300) of the summer. A third, unexposed set served as control (CT). After the experimental trial, the fish were evaluated for fitness indices, including thermal tolerance and respiratory metabolic rates. Important physiological, genotoxic, molecular and histological changes were also evaluated in the blood plasma and body tissues. Among the welfare indices, routine and maximum metabolic rates and lower critical temperature increased, whereas thermal scope decreased in the UVB-exposed fish. The exposure caused a significant increase in the total antioxidative capacity (TAC), nitric oxide (NO), cholesterol, cortisol, and aminotransferases in the plasma. However, the antioxidative enzyme levels significantly decreased, whereas malonaldehyde levels increased in the kidney and liver of the UVB-exposed fish, dose-dependently. In addition, the dehydrogenase enzyme (LDH and MDH) activities significantly increased in the liver, kidney, and muscle, dose-dependently. Among the non-specific immune parameters, plasma lysozyme, neutrophil respiratory burst activity, and total blood leucocyte count also increase dose-dependently. Molecular analysis revealed that the antioxidative pathway genes (<em>gst, cat1, sod1,</em> and <em>cyp1a1</em>) and immune gene (<em>nf-κb2</em>) were differentially expressed in the liver, kidney, and muscle tissues of the UVB-exposed fish, showing an overall downregulatory trend. The cortisol-related gene, <em>hsd11b1a</em>, was upregulated in the kidney and downregulated in the liver of the UVB-exposed fish. Moreover, UVB exposure resulted in structural, non-pathogenic changes in the gill, liver, and kidney. Our study showed that although prolonged exposure to ambient UVB radiations did not affect the physiology of the fish beyond their threshold, it did increase the energetic costs and affected the antioxidative mechanisms. The results indicate that any further increase in the environmental UVB can harm the welfare of the fish, both in the wild and captivity, in high-altitude regions.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"605 ","pages":"Article 742496"},"PeriodicalIF":3.9,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767490","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":"Effective control of Neobenedenia girellae infestation by an optimized oral protocol in greater amberjack juveniles (Seriola dumerili)","authors":"Raquel Quirós-Pozo ,&nbsp;Christian Monzón ,&nbsp;Sarah Montesdeoca-Esponda ,&nbsp;María Esther Torres-Padrón ,&nbsp;Javier Roo","doi":"10.1016/j.aquaculture.2025.742500","DOIUrl":"10.1016/j.aquaculture.2025.742500","url":null,"abstract":"<div><div>Infestations by <em>Neobenedenia girellae</em> constitute significant challenges to the culture of greater amberjack (<em>Seriola dumerili</em>), a promising species for aquaculture diversification. The impact of these infestations is further amplified by global ocean warming, underscoring the urgent need for effective prevention and control measures. This study assessed the efficacy of different praziquantel (PZQ) treatments on growth performance, muscle kinetic profiles (Experiment 1), and their ability to control <em>N. girellae</em> infestations in <em>S. dumerili</em> juveniles reared in an open seawater system (Experiment 2). In Experiment 1, six treatments were tested: T1 (Control), T2-PZQ 2.25 %-1 (450 mg PZQ/kg live weight, single dose), T3-PZQ 1.125 %-2 (225 mg PZQ/kg live weight, 2 days), T4-PZQ 0.75 %-3 (150 mg PZQ/kg live weight, 3 days), T5-PZQ 0.75 %-2 (150 mg PZQ/kg live weight, 2 days), and T6-PZQ 0.75 %-1 (150 mg PZQ/kg live weight, single dose). In Experiment 2, protocols T1–T4 were evaluated. Results indicated that growth performance was unaffected by PZQ treatments, and muscle PZQ concentrations returned to baseline within 48 h post-administration. Protocols T3–1.125 %-2 and T4–0.75 %-3 exhibited the highest efficacy against <em>N. girellae</em> adults, achieving 91 % and 99.8 % parasite reduction, respectively. The protocol involving 150 mg PZQ/kg administered over three consecutive days proved to be the most effective for managing <em>N. girellae</em> infestations, without compromising fish growth and with minimal muscle residue persistence.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"605 ","pages":"Article 742500"},"PeriodicalIF":3.9,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767488","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 formation of a hybrid fish derived from Labeo rohita ♀ × Cyprinus carpio ♂ and exhibiting stronger low temperature tolerance","authors":"Jiali Lin ,&nbsp;Haoran Zhang ,&nbsp;Jietao Wang ,&nbsp;Bing Fu ,&nbsp;Zexun Zhou ,&nbsp;Wuhui Li ,&nbsp;Huirong Yang ,&nbsp;Shaojun Liu","doi":"10.1016/j.aquaculture.2025.742498","DOIUrl":"10.1016/j.aquaculture.2025.742498","url":null,"abstract":"<div><div>Temperature is a critical environmental factor that influences the distribution of species and impacts life activities such as development, growth, physiology, and metabolism. In China, the rearing range of Roho labeo (<em>Labeo rohita</em>) has been restricted due to its limited low temperature tolerance. In this study, a hybrid population, designated RLC, was produced from <em>Labeo rohita</em> (RL, 2n = 50) (♀) × <em>Cyprinus carpio</em> (CC, 2n = 100) (♂). Comparative analyses of morphological traits, DNA content, and chromosome numbers revealed that RLC (2n = 75) is a hybrid fish, with the genotype and phenotype distinct from its parent species. RLC demonstrated enhanced low temperature tolerance compared to RL, the CTmin (9.04 ± 0.83 °C) and T_LD50 (4.1 °C) for RLC were markedly lower than RL (12.08 ± 1.25 °C, 7.2 °C). Biochemical indices and histological analysis indicated that low temperature stress induced structural damage and oxidative stress in the liver, gills, and brain of both RLC and RL, with notable improvements in RLC compared with RL. The joint analyses of transcriptomics and metabolomics showed that metabolic pathways in the liver of RLC were most significantly impacted by low temperature stress. Additionally, regulation of lipid metabolism appears to be vital for the response of RLC to low temperature stress. Our findings contribute to the understanding of distant hybridization and the molecular mechanisms underlying the response to low temperature stress in fish.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"605 ","pages":"Article 742498"},"PeriodicalIF":3.9,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767487","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":"Environmental adaptability, virulence, and immune evasion mechanisms of Edwardsiella piscicida in the largemouth bass (Micropterus salmoides)","authors":"Changyi Lin,&nbsp;Biao Jiang,&nbsp;Weimin Huang,&nbsp;Wenhao Wu,&nbsp;Jiahao Zhang,&nbsp;Youlu Su","doi":"10.1016/j.aquaculture.2025.742505","DOIUrl":"10.1016/j.aquaculture.2025.742505","url":null,"abstract":"<div><div><em>Edwardsiella piscicida</em>, an emerging fish pathogen, has caused significant economic losses to the aquaculture industry. This study aimed to investigate the biological characteristics, infection process, and environmental impact on the pathogenicity of <em>E. piscicida</em> in the largemouth bass (<em>Micropterus salmoides</em>). <em>E. piscicida</em> strain FSMS2108 was isolated from infected largemouth bass and identified through molecular and phenotypic analyses. Strain FSMS2108 exhibited growth at pH 5–9 and salinity at 5–30 ppt, with optimal growth at neutral pH and low salinity. It carried nine virulence genes and exhibited phospholipase activity. An immersion infection model revealed that strain FSMS2108 could infect largemouth bass through mucosal surfaces, leading to high mortality. Environmental factors, including water temperature and dissolved oxygen content, significantly affect the cumulative mortality rate of largemouth bass infected with strain FSMS2108. Bacterial load and histopathological analyses showed that strain FSMS2108 primarily colonized the gills, skin, and spleen, spreading systemically via the bloodstream and causing widespread tissue damage. Transmission electron microscopy revealed that strain FSMS2108 proliferated within splenic macrophages. Gene expression analysis indicated that strain FSMS2108 interfered with host immune responses and inhibited apoptosis, primarily through upregulation of anti-apoptosis genes and downregulation of pro-apoptosis genes. These findings provide insights into the infection mechanism and environmental adaptability of strain FSMS2108 in the largemouth bass, highlighting the importance of environmental management for disease prevention and control.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"604 ","pages":"Article 742505"},"PeriodicalIF":3.9,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767711","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":"Development of a colorimetric loop-mediated isothermal amplification (cLAMP) assay for the rapid and visual detection of Aeromonas dhakensis infection in aquaculture","authors":"Suat Moi Puah ,&nbsp;Wei Ching Khor ,&nbsp;Yen Ching Lim ,&nbsp;Kyaw Thu Aung ,&nbsp;Tien-Tien Vicky Lau ,&nbsp;Chen Chen Yong ,&nbsp;Po Teen Lim ,&nbsp;Chui Pin Leaw ,&nbsp;Kek Heng Chua","doi":"10.1016/j.aquaculture.2025.742483","DOIUrl":"10.1016/j.aquaculture.2025.742483","url":null,"abstract":"<div><div><em>Aeromonas dhakensis</em>, an emerging zoonotic pathogen prevalent in aquatic environments, poses a significant threat, particularly in causing motile <em>Aeromonas</em> septicemia in aquaculture and food safety concerns. Timely detection of the pathogen is crucial for effective management<em>.</em> Herein, we develop a colorimetric loop-mediated isothermal amplification (cLAMP) assay for rapid, accurate, and convenient detection of <em>A. dhakensis</em> targeting ricin B lectin domain. The assay enabled naked-eye detection of the <em>A. dhakensis</em> nucleic acid within 20 min, based on a colour change from pink to yellow. The detection limit of the cLAMP assay was 50 pg of defined plasmid control DNA (equivalent to 1.43 × 10⁷ copies/μL) or approximately 1.0 × 10⁶ CFU/mL of whole genome DNA extracted from pure bacterial culture, in a 10 μL reaction. The assay demonstrated high specificity, yielding positive results in all 93 <em>A. dhakensis</em> samples and showing no cross-reaction with 24 non-target samples. Performance was further evaluated by comparing cLAMP results with qPCR in 117 bacterial samples, achieving 100 % concordance between the two methods. In summary, our findings demonstrate the simplicity, high sensitivity and accuracy of the cLAMP for <em>A. dhakensis</em> detection, making it as a valuable tool for rapid identification of this species within the <em>Aeromonas</em> genus, which is crucial for effective disease management.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"605 ","pages":"Article 742483"},"PeriodicalIF":3.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792562","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":"Seasonal dynamics of gut microbiota in Chinese soft-shelled turtles (Pelodiscus sinensis): Implications for sustainable aquaculture practices","authors":"Zuobing Zhang ,&nbsp;Deqi Wang ,&nbsp;Peng Xiao ,&nbsp;Na Liu ,&nbsp;Roy A. Dalmo ,&nbsp;Cuijuan Niu","doi":"10.1016/j.aquaculture.2025.742504","DOIUrl":"10.1016/j.aquaculture.2025.742504","url":null,"abstract":"<div><div>The gut microbiota significantly influences host health, yet its seasonal dynamics in reptiles—especially in farmed species like Chinese soft-shelled turtle (<em>Pelodiscus sinensis</em>)—remain largely unexplored. Considering the unique physiology of reptiles and their distinct seasonal behaviors, understanding these dynamics is crucial for optimizing management strategies. This study investigated seasonal changes in the gut microbiota of Chinese soft-shelled turtles and the underlying community assembly mechanisms. Large intestine samples were collected and analyzed using 16S rRNA gene sequencing, with seven samples obtained each season. Results indicated that summer exhibited significantly higher richness than autumn and winter, as confirmed by the Shannon and Simpson indices, while evenness was significantly greater in summer compared to autumn with a near-significant trend versus winter (<em>P</em> = 0.053). Beta diversity analysis showed significant seasonal clustering, indicating seasonality's impact on the gut microbiota structure. Dominant phyla included Firmicutes, Bacteroidota, Proteobacteria, and Actinobacteriota. The relative abundance of Bacteroidota increased during autumn and winter, while Firmicutes decreased, suggesting an energy source shifts during hibernation. Functional predictions indicated seasonal differences in glycan biosynthesis and metabolism pathways. Community assembly analysis indicated increased stochastic processes in autumn and winter, while deterministic processes dominated in summer. This shift towards stochastic processes during colder seasons likely results from greater environmental variability, such as temperature fluctuations and reduced food availability. Fourteen operational taxonomic units were shared across all seasons, displaying cooperative interactions. The presence of potentially pathogenic genera like <em>Edwardsiella</em> and <em>Aeromonas</em> in winter suggested a possible link to post-hibernation mortality. These findings provide valuable insights into how Chinese soft-shelled turtles adapt to seasonal changes through gut microbiota shifts, offering improved knowledge for aquaculture management.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"604 ","pages":"Article 742504"},"PeriodicalIF":3.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759797","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 and functional characterization of grass carp TRPV1 in facilitating GCRV infection","authors":"Zi-Yu Xie ,&nbsp;Yang Xu ,&nbsp;Qiu-Shi Zhang,&nbsp;Zhi-Ming Liu,&nbsp;Liang Hu,&nbsp;Wei Wang,&nbsp;Tiao-Yi Xiao,&nbsp;De-Liang Li,&nbsp;Xin-Yu Liang,&nbsp;Jun-Hua Li","doi":"10.1016/j.aquaculture.2025.742484","DOIUrl":"10.1016/j.aquaculture.2025.742484","url":null,"abstract":"<div><div>The transient receptor potential vanilloid (TRPV) channels constitute a distinct category of sensory signal mediators, responsible for transmitting signals from both internal and external environmental stimulus. The outbreaks of aquatic viral diseases, such as grass carp haemorrhagic disease (GCHD) caused by grass carp reovirus (GCRV) infection, are typically seasonal and temperature-dependent, while the molecular mechanism underlying this temperature dependence remains largely unknown. In this study, we investigated and characterized the roles of CiTRPVs from grass carp (<em>Ctenopharyngodon idellus</em>) in response to GCRV infection. CiTRPVs were ubiquitously expressed across all examined tissues and exhibit significant upregulation in expression levels following stimulation with GCRV or pathogen-associated molecular patterns (PAMPs). Temperature-gradient infection and temperature-stress infection experiments discovered that GCRV induces the expression of CiTRPV1 in a temperature-dependent manner, with the permissive temperature 28 °C promoting both the expression of CiTRPV1 and the proliferation of GCRV. Further immunofluorescence analysis revealed that CiTRPV1 exhibits a widespread cellular distribution, while viral infection enhances its oligomerization and co-localization with mitochondria (Mit) and endoplasmic reticulum (ER). Additionally, the overexpression of CiTRPV1, knockdown using small interfering RNA (siRNA), and pharmacological inhibition/activation approaches demonstrated that CiTRPV1 facilitated GCRV replication. Lastly, CiTRPV1 promoted GCRV infection by inducing heat shock proteins (HSP70 and HSP90), inflammatory factors (interleukin 6, IL6), and membrane receptors (integrin). This study elucidated the immune evasion mechanism whereby aquatic viruses exploit sensory TRP channels to enhance viral infection, offering potential targeted prevention and treatment strategies for GCHD through the use of CiTRPV1 inhibitors, while highlighting the crucial role of environmental factors in the development of aquatic viral diseases.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"604 ","pages":"Article 742484"},"PeriodicalIF":3.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767712","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":"Role of brain-gut axis in modulating stress responses via neurotransmitters and cytokines in largemouth bass (Micropterus salmoides) under acute crowding stress","authors":"Leshan Yang ,&nbsp;Meijia Li ,&nbsp;Jia Zhang ,&nbsp;Ying Liu","doi":"10.1016/j.aquaculture.2025.742502","DOIUrl":"10.1016/j.aquaculture.2025.742502","url":null,"abstract":"<div><div>Acute crowding stress is typically evident during transport or handling stages in aquaculture, where it has severe consequences on fish gut health. However, the underlying mechanism of how acute crowding stress impacts fish gut health has been largely unexplored. In this study, the role of brain-gut axis in modulating the acute crowding stress response was explored in juvenile largemouth bass (<em>Micropterus salmoides</em>). After 3 h of acute crowding stress, a notable decrease in cortisol level was observed in the brain region of the telencephalon, whereas a significantly increase was seen in the serum. Additionally, neurotransmitters of dopamine (DA) and serotonin (5-HT) underwent significantly alterations both in brain regions and serum. Specifically, DA content decreased significantly in the telencephalon, hypothalamus, and remaining brain regions, but increased markedly in the serum. Conversely, 5-HT content significantly decreased in the telencephalon, but increased significantly in the medulla oblongata and serum. Furthermore, a significant upregulation of inflammatory cytokines, including IL-1β, IL-10, TNF-α, and IFN-γ was observed in six brain regions, serum, and gut after acute crowding stress. Concurrently, notable alterations in gut structure were evident, with significant changes in the width and height of gut villi, goblet cell count, and mucus secretion. The gut permeability of fish also increased significantly. Moreover, the gut microbiota composition underwent significant changes after acute crowding stress, with a notable elevation of <em>Bacteroides</em> and <em>Escherichia-Shigella</em> in the foregut and <em>Corynebacterium</em> and <em>Enhydrobacter</em> in the hindgut. These findings provide valuable insight into the response mechanisms of the acute crowding stress in fish through the brain-gut axis.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"604 ","pages":"Article 742502"},"PeriodicalIF":3.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759795","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":"Evaluating metabolic rate and specific dynamic action in recirculating aquaculture systems: Influence of stocking density and feeding level in barramundi (Lates calcarifer)","authors":"Le Boucher Richard,&nbsp;Chung Weiqiang,&nbsp;Ng Jessalin,&nbsp;Tan Shun En Lydia,&nbsp;Lee Co Sin","doi":"10.1016/j.aquaculture.2025.742503","DOIUrl":"10.1016/j.aquaculture.2025.742503","url":null,"abstract":"<div><div>Bioenergetic modelling plays a crucial role in aquaculture, optimizing nutrition, growth prediction, husbandry, and genetic management. The estimation of animal metabolic rate (MR), traditionally conducted in closed respirometric chambers, is a fundamental aspect of these models. This study presents a novel method for directly measuring fish MR, routine metabolic rate (RMR), postprandial peak metabolic rate (PMR), and specific dynamic action (SDA) parameters including SDA coefficient (C_SDA) within a recirculating aquaculture system (RAS). Additionally, the study evaluates the effects of fish size, stocking density, and feeding levels on these metabolic metrics. Using 3510 barramundi (<em>Lates calcarifer</em>, 51.2 g) housed in 27 RAS tanks (1 m³, 30.0 °C seawater), dissolved oxygen levels every 10 min for 56 days to model metabolic parameters. Fish MR ranged from 14.5 to 112.8 mg O₂ fish⁻¹ h⁻¹, following a daily sinusoidal pattern. PMR fit a power model (PMR = 2.18 × body weight [BW]^0.71, R² = 0.70, <em>n</em> = 810), while RMR followed an exponential model (RMR = 6.31 × exp. (0.01 × BW), R² = 0.87, <em>n</em> = 148). SDA parameters remained largely unaffected by stocking density or feeding rate (<em>P</em> &gt; 0.05), with time-to-peak = 8.8–10.7 h, total SDA duration = 22.1–22.6 h, SDA factual scope = 2.0–2.9, and C_SDA = 14.8–16.4 %. Although this RAS-based methodology does not match the precision of closed-chamber respirometry, the results closely align with previous findings. This approach therefore provides a scalable tool for phenotyping metabolic variations in commercial aquaculture.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"604 ","pages":"Article 742503"},"PeriodicalIF":3.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143767713","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":"Exploring cryomedium with hypotonic extender for sturgeon sperm cryopreservation","authors":"Aleksandra Krasilnikova,&nbsp;Marek Rodina,&nbsp;David Gela,&nbsp;Anatolii Sotnikov,&nbsp;Martin Pšenička","doi":"10.1016/j.aquaculture.2025.742497","DOIUrl":"10.1016/j.aquaculture.2025.742497","url":null,"abstract":"<div><div>This study investigates sperm cryopreservation across multiple sturgeon species (sterlet, Siberian, Russian, and stellate sturgeons), testing different cryomedia and two cryopreservation formats: small 0.5 ml plastic straws, rapidly cooled on a polystyrene raft within a Styrofoam box, and larger 4.5 ml and 10 ml cryotubes subjected to a controlled, slow cooling process in a programmable freezer. The cryomedia tested included a novel hypotonic (relative to the osmolality of seminal plasma) extender containing 1 mM KCl, methanol, and ethylene glycol at varying concentrations, alongside traditional cryomedium. The study assessed the impact of cryomedia on spermatozoa volume changes during the equilibration period, fertilization success, and embryogenesis. Notably, the cryoprotectants ethylene glycol and methanol affected sperm cell volume differently: ethylene glycol caused initial shrinkage, followed by volume normalization, whereas methanol did not induce significant changes in spermatozoa volume. Key findings demonstrated that a cryomedium with a hypotonic extender containing 1 mM KCl, 11 % methanol, and 2.5 % ethylene glycol effectively preserved post-thaw sperm motility, achieving 46 ± 6 % in both 0.5 ml straws and 4.5 ml cryotubes for Siberian sturgeon; 31 ± 10 % in 0.5 ml straws and 40 ± 12 % in 10 ml cryotubes for Russian sturgeon; and 46 ± 10 % in 0.5 ml straws, 39 ± 8 % in 4.5 ml cryotubes, and 44 ± 11 % in 10 ml cryotubes for Stellate sturgeon. The cryomedium also supported high embryo development and hatching rates, with Siberian sturgeon achieving 81 ± 16 % and 79 ± 15 % in 0.5 ml straws, and 84 ± 6 % and 82 ± 7 % in 4.5 ml cryotubes. For Russian sturgeon, development and hatching rates were 60 ± 20 % and 57 ± 20 % in 0.5 ml straws, 51 ± 12 % and 48 ± 13 % in 4.5 ml cryotubes, and 62 ± 11 % and 48 ± 13 % in 10 ml cryotubes. These results highlight the effectiveness of this alternative cryopreservation approach across different sturgeon species and sample volumes. However, spermatozoa from cryopreserved samples with the 1 mM KCl extender showed a statistically significant reduction in curvilinear velocity (VCL) compared to fresh sperm and spermatozoa cryopreserved in traditional cryomedia. Nevertheless, fertilization success was not affected, and no significant morphological abnormalities were observed in the resulting embryos. This study introduces an alternative cryopreservation protocol for sturgeon species, demonstrating the feasibility of using cryomedium with 1 mM KCl extender and large sample volumes (4.5 ml and 10 ml cryotubes) without compromising fertilization outcomes. The findings contribute to advancing cryopreservation techniques, offering promising new possibilities for sturgeon aquaculture and conservation.</div></div>","PeriodicalId":8375,"journal":{"name":"Aquaculture","volume":"605 ","pages":"Article 742497"},"PeriodicalIF":3.9,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143783705","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}