Abstract Piezoresistive wearable sensors are a widely studied topic today. Research into flexible wearable sensors has attracted interest as the Internet of Things continues to advance. Designing and producing these sensors using the biomimetic method that imitates structures in nature makes it possible to create much more sensitive and cost‐effective sensors. Polydimethylsiloxane (PDMS)‐based sensors, which stand out in terms of flexibility and durability, are among the main areas where smart wearable sensor technologies work. In this study, flexible piezoresistive sensors inspired by Cyprinus carpio scales were produced. For this purpose, sensor bases were first produced by transferring the symmetric patterns of carp scales onto PDMS polymer. Then, PEDOT: PSS conductive polymers were deposited on the PDMS molds with the patterns of Cyprinus carpio scales using the ultrasonic spray pyrolysis method. The sensors were created by optimizing the conductivity of PDMS molds with PEDOT: PSS and investigating their electrical characterizations under sinusoidal mechanical triggers using a tensile test system. Three‐dimensional structures with gradient symmetry in fish scales enhance sensor response and recovery times, achieving 40 and 39 ms, respectively, even at voltages below 0.05 V. © 2026 Society of Chemical Industry.

Proteomic profiling of gills during carp edema virus infection provides insights into immune responses and cellular stress associated with koi sleepy disease.

This study evaluated the effects of dietary supplementation with Bacillus coagulans and/or the brown macroalga Dictyota dichotoma on growth, blood biochemical indices, immune responses, redox status, and gene regulation in common carp (Cyprinus carpio). A total of 400 fingerlings (initially weighing, 3.0 ± 0.03g) were randomly divided into 40 hapas (10 fish per hapa). These hapas were assigned into equal 8 experimental groups (each group contain five replicates). The groups included: a control (no supplementation), B. coagulans alone (2g/kg), D. dichotoma at 2.5, 5, and 10g/kg (D1, D2, D3), and combinations of B. coagulans (2g/kg) with each level of D. dichotoma (BC*D1, BC*D2, BC*D3). After 8 weeks of feeding, the results indicated that the diet supplemented with 10g/kg of D. dichotoma (D3), either alone or in combination with BC, significantly enhanced growth performance, feed conversion ratio (FCR), and feed efficiency ratio (FER). Meanwhile, the fish group fed 2g/kg of BC showed a notable improvement in feed utilization parameters, although its impact on growth was limited. The whole-body chemical analysis results showed that either BC or D. dichotoma alone significantly increased ash content while decreasing protein and lipid levels in a dose-dependent manner. In contrast, the combined BC*D3 group significantly enhanced protein retention levels while reducing ash and lipid content. Notably, D3-fed fish showed the highest serum protein content and reduced liver enzyme activities. In contrast, BC alone significantly lowered both liver and kidney health indicators. Additionally, significant interactions between BC and D3 were observed for protein fraction levels, AST, and kidney function enzymes, with the combined BC and D3 treatment resulting in the most favorable profile. Furthermore, immunity measurements, including lysozyme, complement C3, IgM, and IgD, improved significantly with the combined supplementation of BC and a high level of D. dichotoma. Additionally, the dietary administration of both BC and 10g/kg D. dichotoma significantly boosted antioxidant enzyme activities (glutathione peroxidase, catalase, and superoxide dismutase) while reducing MDA levels. Additionally, co-supplementation significantly upregulated hepatic expression of IL-6, IL-10, and TNF-2α. These findings highlight the synergistic potential of dietary supplementation with 2g/kg Bacillus coagulans and 10g/kg Dictyota dichotoma as effective functional feed additives for enhancing growth performance, immune responses, and oxidative stress resistance in common carp aquaculture.

The common carp (Cyprinus carpio) is an invasive species in Argentinian Patagonia. This study aimed to investigate the presence of Circoviridae-related viruses associated with its population in the Negro River. Total DNA samples extracted from the organ pools of 50 individuals were evaluated using a broad-spectrum PCR, which led in a single case to the detection of a circo-like virus. Based on the partial rep sequence obtained, phylogenetic analysis showed a relation between the virus found and those that have been identified in other cyprinid fishes, such as gudgeon (Gobio gobio) and fathead minnow (Pimephales promelas). The results propose the occurrence of a previously undescribed circo-like virus in Patagonian common carp.

This is the first study on monogenean ectoparasites of five cyprinoid fish species Cyprinus carpio, Carassius gibelio, Carassius auratus, Acanthobrama marmid and Chondrostoma regium in the Karakaya Dam Lake, on the Euphrates river. Fish species were obtained from a commercial fisherman in the period from December 2024 to June 2025. Ten gill monogenean parasites belonging to three different genera (Dactylogyrus, Gyrodactylus, Eudiplozoon) were identified. These are Dactylogyrus anchoratus, D. anoigeus D. achmerowi D. extensus, D. elegantis, D. sphyrna, D. vistulae, Eudiplozoon nipponicum, Gyrodactylus sprostonae and Gyrodactylus sp. The percentage of occurrence, mean intensity and abundance values of the identified monogenean species in their hosts were The similarity of the monogenean parasite fauna of five cyprinoid fish species was compared. The most common monogenean species is D. anchoratus, which has been identified in Carasius auratus, C. gibelio and C. carpio. All the monogenean species were recorded for the first time in the Karakaya Dam Lake. Dactylogyrus anoigeus and D. achmerowi are new records for Turkish fish parasite fauna, while E. nipponicum for A. marmid and C. gibelio, D. sphyrna for A. marmid are a new parasite records. Furthermore, the D. extensus and G. sprostonae on C. auratus is reported for the first time in Türkiye.

Streptococcus agalactiae is a multi-host pathogen and a major threat to aquaculture, particularly tilapia production. This study characterised the serotype distribution and virulence gene profiles of 97 S. agalactiae isolates obtained from non-tilapia freshwater species in Vietnam, including carp species not previously recognised as hosts, namely black carp, grass carp and common carp. Three serotypes were identified among non-tilapia isolates, Ia (44.3%), III (39.2%) and Ib (16.5%). Virulence gene distributions varied substantially within and between serotypes; however, all isolates consistently carried the fbsA and cfb genes. Distinct serotype-associated gene patterns were observed. Serotype Ia isolates possessed fbsA, fbsB, bca, hylB and cfb but lacked lmb and spb1-F, whereas serotype III isolates harboured pavA, cylE, fbsA, lmb, scpB, cfb and cspA but lacked bac. Serotype Ib isolates carried pavA, cylE, fbsA, hylB, cfb and cspA, while spb1-F and bac were absent. Overall, this study identifies additional non-tilapia hosts of S. agalactiae in freshwater aquaculture provides the first evidence of infection in black carp, grass carp and common carp. These findings demonstrate the diversity of circulating serotypes and virulence gene profiles. These findings indicate increasing epidemiological complexity and highlight the need for integrated prevention and disease management strategies targeting this pathogen.

Bioconversion of heavy metals in river sediments: Seasonal dynamics, driving mechanisms, and BSAF-based assessment in the Liujiang River basin.

Apigenin alleviates DFZ-induced cardiac, renal, and intestinal injury in carp by modulating oxidative stress and inflammatory responses.

Synergistic effects of koi herpesvirus infection and nanoplastic exposure on the physiological and immune responses of koi carp.

Nanotechnology has gained significant attention due to its diverse application history, particularly the silver nanoparticles(AgNPs), which are different from other nanomaterials due to their strong and broad-spectrum antimicrobial activity. Therefore, this study developed a sustainable approach for synthesizing AgNPs using vegetable waste extract, characterizing them using Uv-vis spectrometer and scanning electron microscopy (SEM) to confirm spherical, crystalline, and undersized nanoparticles(NPs). In a 30-day dietary exposure trial withCyprinus carpio, fish fed AgNP-supplemented feed exhibited significant growth retardation, including reduced weight gain, alongside elevated oxidative stress marked by increased catalase (218.51 ± 6.87), superoxide dismutase (243.33 ± 5.82), (430.27 ± 5.39), and (157.68 ± 4.50) activities in gills and brain, respectively at the 6 mg/L. Histopathological analysis revealed severe gill histological alterations i.e., (lamellar fusion, epithelial lifting), muscular degeneration (fiber necrosis, degeneration), and intestinal damage (villus atrophy, lymphocytes infiltration), indicating systemic toxicity. These findings solve two major problems, i.e., environmental cleanness by shifting vegetable residue into fine particles and a potential aquatic toxicity.

A novel phage and its protective effects against Hafnia paralvei in Cyprinus carpio Koi

Yi’an Reservoir is located on a major tributary of the Baoquan River and hosts abundant aquatic resources, with Cyprinus carpio, Carassius auratus, and Hemiculter leucisculus as the dominant fish species. Water quality parameters significantly shape fish gut microbiota, which in turn plays a crucial role in host physiological functions. This study aimed to characterize the water quality parameters in Yi’an Reservoir and identify the microbial communities in both the aquatic environment and fish guts (C. carpio, C. auratus, and H. leucisculus) through 16S ribosomal RNA sequencing. The objective was to examine the associations of water quality parameters and aquatic environmental microbiota with the assembly of gut microbial communities in fish inhabiting this reservoir system. The water quality parameters showed significant site-specific differences, of which temperature and dissolved oxygen were highest at Location B, while pH was highest at Location A. The Cyanobium_PCC-6307 was identified as a major differentially abundant taxon at the genera level across different sampling sites. Furthermore, the gut microbiota of the same fish species exhibited substantial variation across different sampling sites. Redundancy analysis identified distinct environmental drivers at each location. Specifically, pH, conductivity, and total dissolved solids (TDS) showed positive correlations with the gut microbiota at Location A. In contrast, temperature, dissolved oxygen (DO), and the environmental abundance of Cyanobium PCC-6307 were positively correlated with the gut microbiota at Locations B and C. This study provides important insights for the conservation and management of aquatic resources in reservoir ecosystems.

Adverse effects of 6PPD-quinone bioaccumulation at environmentally relevant concentrations on Cyprinus carpio growth and development.

Microplastics (MPs) are emerging contaminants in aquatic ecosystems and are able to modify the bioavailability and toxicity of co-occurring chemicals. In the present study, it was investigated whether high-density polyethylene (HDPE)-MPs exacerbate the toxicological effects of the pyrethroid insecticide deltamethrin in juvenile common carp (Cyprinus carpio). Fish (n = 270; 25 ± 5 g) were randomly allocated to a 2 × 3 factorial design (three replicates per group; 15 fish per tank) and exposed for 30 days to sub-lethal deltamethrin (12.5 μg/L; 10% of 96-h LC₅₀) and/or HDPE-MPs (0, 350, or 700 μg/L; 200-250 μm). Hepatic detoxification- and antioxidant-related gene expression was quantified, together with redox status, oxidative damage, and plasma biochemical biomarkers of organ function and injury. Deltamethrin and MPs alone altered transcriptional and biochemical endpoints, while co-exposure (particularly with 700 μg/L MPs) produced the most pronounced responses, including stronger induction of detoxification/metal-binding genes, reduced overall antioxidant capacity, and marked increases in lipid peroxidation and protein oxidation. Plasma activities of AST, ALT, ALP, LDH, GGT, and CK increased, and butyrylcholinesterase was inhibited, indicating cellular membrane damage and multi-organ dysfunction. Changes in circulating metabolites and creatinine further supported hepatic and renal impairment, and significant interaction effects for multiple endpoints suggested potentiation of deltamethrin toxicity by MPs. Overall, HDPE MPs act as relevant co-stressors that intensify deltamethrin-driven toxicity in fish, underscoring the need for mixture-aware monitoring and risk assessment in contaminated freshwater environments.

Allotetraploid fish produced by distant hybridization are valuable germplasm for the mass production of sterile triploids. The allotetraploid crucian-carp hybrid (4nAT, 4n = 200) is derived from the intergeneric cross between a female red crucian carp (Carassius auratus red var., 2n = 100) and a male common carp (Cyprinus carpio L., 2n = 100). However, after 33 successive generations, this lineage faces a critical bottleneck in maintaining male fertility. The present study aimed to develop new biomarkers for testicular development and characterize the associated functional gene expression profile in 4nAT. Following whole-genome resequencing and selection signature analysis of 15 male 4nAT individuals from each of the high-development group (HDG) and low-development group (LDG), ZSWIM7 (Zinc Finger SWIM-Type Containing 7), a gene implicated in reproductive development, was selected as a candidate for further fertility association studies. Seven SNPs were screened in the coding region of ZSWIM7 of 70 4nAT males; among these, SNP3 (c.23T/C) exhibited a significant correlation between genotypes and testicular development: individuals with the CT genotype showed a higher gonadosomatic index (1.17 ± 0.68 vs. 0.65 ± 0.50) and greater counts of mature spermatozoa (2537.67 ± 283.95 vs. 341.56 ± 121.66) compared to those with the TT genotype. Further quantitative PCR and immunofluorescence assays demonstrated that ZSWIM7 was highly expressed in the testis and specifically localized to the nuclei of early meiotic primary spermatocytes. Collectively, these results establish ZSWIM7 as a promising biomarker for 4nAT testicular development, offering a potential molecular tool for maintaining male fertility in allotetraploid fish breeding.

Impact of Curcumin as a Natural Food Additive on Physiological Health Indicators in Common Carp (Cyprinus carpio L.)

The purpose of this research was to investigate how adding dietary guar gum to high‐lipid diets affected the fish growth and gut health of common carp (Cyprinus carpio). A normal‐lipid diet (5% crude lipid; control) and four high‐lipid diets (10% crude lipid) with 0% (high‐fat [HF]), 0.3% (GG0.3), 1% (GG1), and 3% (GG3) of guar gum were developed and fed to fish (4.53 g) for 8 weeks. The findings showed that HF induced impairment of intestinal morphology and mucosal barrier, oxidative stress, gut dysbiosis, and gut inflammation. Compared to the HF, guar gum‐containing diets substantially improved gut villus height, upregulated the expression levels of nuclear factor erythroid 2-related factor 2 and zonula occludens-1, and downregulated the expression levels of toll-like receptor 1 (tlr1), tlr5, myeloid differentiation factor 88, interleukin-1β (il-1β), il-6, and il-8. Moreover, the GG0.3 and GG1 diets dramatically increased catalase (cat) and occludin expression levels. Furthermore, the GG1 and GG3 diets improved the microbiota composition by increasing Fusobacteria and Cetobacterium abundance while lowering Proteobacteria, Acidovorax, Acinetobacter, Serratia, and Comamonas abundance. Correlation analysis revealed that guar gum improved gut health by modulating gut microbiota and tight junction proteins. The findings indicated that guar gum can ameliorate HF diet‐induced intestinal damage in fish.

Aim: This study examined the growth performance of six geographical stocks of common carp, Cyprinus carpio a species that tolerates salinity up to 10 ppt, in saline water systems. Methodology: Two growth experiments were conducted under low salinity (S1: 2-4 ppt) and high salinity (S2: 8-10 ppt) levels. In the first experiment (1-225 days), six stocks (MH, MN, TR, MP, HR, AP) were housed separately, and traits like body weight, length, and height were recorded. In the second experiment (225-365 days), fish were tagged and communally reared, with males and females kept separately. Results: Significant variations in Body weight (Bw), Body length (Bl), and Body height (Bh) were observed among the stocks in the first experiment, with the MH stock performing best. In the second experiment, the least squares means of Bw was 354.59±10.04 g in S1 and 335.99±10.12 g in S2. The effect of Bw at tagging, salinity and sex by salinity interaction had a significant effect on Bw and Bh. Females in the S1 group exhibited the highest growth metrics (376.19±10.39 g, 21.39±0.43 cm, and 8.23±0.10 cm for Bw, Bl and Bh, respectively). Heritability estimates for growth traits (Bw: 0.11 ± 0.06; Bl: 0.12 ± 0.07; Bh: 0.11 ± 0.06) indicated moderate genetic variability, supporting the potential for a selective breeding program to develop fast growing common carp for inland saline aquaculture. Interpretation: The study demonstrates the potential of selective breeding in common carp to culture in saline environment, offering a sustainable solution for utilizing degraded saline soils. Key words: Common carp, Growth performance, Inland saline aquaculture, Salinity tolerance

cDNA cloning, expression analysis, and subcellular localization of TRIM13 gene in zebrafish.

Biological invasions pose substantial economic threats globally, yet detailed cost assessments for many Global South nations, especially in Africa, remain scarce. This study presents the first comprehensive breakdown of the potential economic costs of biological invasions in Morocco. We identified 343 invasive alien species, comprising approximately 1.11% of the country’s biodiversity. Using the InvaCost database, we retrieved cost estimates for 137 species with available records. We calculated the mean annual cost per species, adjusted these values both socio-economically (using World Bank Purchasing Power Parity) and climatically (via Köppen climatic regions), and extrapolated them based on species prevalence in Morocco. This yielded an estimated annual economic impact ranging from US$1.14 billion (conservative adjusted value) to US$5.13 billion (maximum scenario). Across all estimations, damage costs consistently exceeded management costs by one or two orders of magnitude. Plant feeding insects such as Phenacoccus madeirensi, Bemisia tabacci, and Cydia pomonella emerged among the costliest species, threatening agriculture and food security. High-impact animals included the Asian tiger mosquito (Aedes albopictus) and the brown rat (Rattus norvegicus), both affecting public health and social welfare. In freshwater systems the common carp (Cyprinus carpio) imposed substantial fisheries losses. Invasive plants, particularly Euphorbia and Cenchrus species, were also widespread and contributed heavily to projected costs. Despite challenges in extrapolating cost data from other regions, this study underscores the urgent need for more research and for targeted management and policy interventions to minimize the spread of invasive species and reduce their economic toll. Proactive measures in Morocco, coupled with international collaboration, will be critical to mitigating this socio-ecological crisis and ensuring long-term sustainability.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-31767-8.