ABSTRACT Social behavior is a fundamental phenotype across vertebrates. Zebrafish ( Danio rerio ) have emerged as a valuable translational model for investigating the neurobiological mechanisms underlying sociability, particularly due to their robust shoaling behavior and experimental tractability. However, the literature presents issues of reproducibility and inconsistent findings regarding the modulation of social preference and shoal cohesion in adult zebrafish. We conducted a systematic review and meta-analysis to synthesize studies evaluating the effects of pharmacological interventions that modulate the central nervous system and stress-related interventions on social behavior in adult zebrafish and, when available, anxiety-like behavior. The literature search was performed in three databases (Embase, PubMed, and Web of Science), followed by a two-step screening process based on inclusion/exclusion criteria. The included studies underwent extraction of qualitative and quantitative data, as well as risk of bias assessment. Interventions from the included studies (n = 108) were categorized according to their nature, mechanism of action, and/or therapeutic purpose, resulting in seven, four, and five meta-analyses for social preference, shoal cohesion, and anxiety-related tests, respectively. Ethanol, NMDA antagonists, pro-dopaminergic agents, and stress-related interventions decreased social preference, while stress-related interventions increased shoal cohesion. The fact that stress produced opposite effects suggests that these paradigms measure distinct sociability constructs, or perhaps are differentially modulated by confounding factors, like anxiety for example. The studies presented high heterogeneity, with prediction intervals compatible with effects in both directions, as well as methodological limitations and deficiencies in data reporting, as evidenced by the risk of bias assessment. These findings emphasize the need for well-designed new studies to validate the findings and expand the evidence on interventions that currently lack sufficient studies for quantitative synthesis.
Stress-related disorders encompass diverse behavioral alterations, including impaired social functioning. The zebrafish (Danio rerio) is a valuable model for studying these phenomena, particularly because of its robust and ethologically conserved social behaviors. Unpredictable chronic stress (UCS) produces behavioral, physiological, and molecular changes in zebrafish that parallel core features of human anxiety and depressive disorders; however, its impact on social outcomes remains unclear. Here, we examined whether a 14-day UCS protocol alters social behavior in adult zebrafish using two complementary assays: the social preference test and the shoal cohesion test. Across two independent experiments, UCS did not elicit detectable changes in individual social approach or group-level cohesion. In contrast, UCS induced clear anxiety-like behavior in the novel tank test, validating the stress manipulation, with stressed fish displaying reduced vertical exploration and decreased time in the upper zone. Distance-based shoal dispersion measures increased over time in both groups, indicating reduced shoal cohesion, consistent with habituation to the testing environment rather than a stress-specific effect. Together, these results suggest that social behavior in adult zebrafish is relatively resilient to UCS under the conditions tested, whereas anxiety-like responses are markedly affected. Future work should investigate whether factors such as stressor intensity, developmental stage, sex composition, or social hierarchy modulate the sensitivity of social behavior to chronic stress.
Background: The reproducibility of preclinical systematic reviews and meta-analyses remains underexplored, particularly when key review decisions are not fully recoverable from the published record. We conducted a direct replication of a published systematic review and meta-analysis on the antidepressant-like effects of minocycline in rodents, complemented by a computational reproduction based on the dataset of the original study. Methods: Searches were performed in PubMed and Web of Science, and study selection, data extraction, and SYRCLE risk of bias assessment were conducted independently by two reviewers. Effect sizes were synthesised using robust variance estimation. Results: We identified 30 potentially eligible studies, including 21 recovered from the original review and nine additional studies. After excluding two studies from the primary quantitative synthesis, 28 studies were retained in the direct replication dataset. The direct replication yielded a somewhat larger pooled effect than the original review (Hedges’ g = −1.21, 95% CI −1.51 to −0.91, compared with g = −1.07, 95% CI −1.41 to −0.74), whereas the computational reproduction matched the published estimate (g = −1.07, 95% CI −1.41 to −0.74). Sensitivity analyses attenuated the estimate but did not alter its direction (risk of bias-adjusted g = −1.06; animal recycling-adjusted g = −0.95). Funnel-plot asymmetry and Egger’s regressions suggested small-study effects. Risk of bias agreement with the original review was limited in several domains, particularly incomplete outcome data and blinding-related domains. Although the direction of the pooled effect was preserved, incomplete reporting of the original workflow required independent decisions regarding search implementation, eligibility assessment, outcome handling, and risk of bias judgments. Conclusions: This replication supports the view that the preclinical literature is broadly consistent with an antidepressant-like effect of minocycline in rodents. However, the magnitude of this effect should be interpreted cautiously in light of small-study effects, methodological limitations, and incomplete transparency in the review workflow.
Social withdrawal is a key component of the negative symptom domain of schizophrenia, and pharmacological blockade of the N-methyl-D-aspartate receptor (NMDAR) is widely used to model schizophrenia-relevant phenotypes in animals. However, findings on social behaviour are inconsistent across paradigms and laboratories. We therefore conducted a systematic review and meta-analysis to synthesise the effects of dizocilpine, ketamine, and phencyclidine on social interaction and social preference, to evaluate whether clinically approved antipsychotics modify these outcomes, and to examine locomotor activity measured within the same social tests to aid interpretation. We searched Embase, PubMed and Web of Science without language or date restrictions. Controlled in vivo studies in laboratory animals administering an eligible NMDAR antagonist and reporting social interaction and/or social preference outcomes were included. Two reviewers independently screened records, extracted data and assessed risk of bias. Effect sizes were computed as standardised mean differences and synthesised using correlated multilevel random-effects models with cluster-robust variance estimation. In total, 264 studies met the inclusion criteria. Overall, NMDAR antagonists were associated with reduced social interaction and reduced social preference relative to controls, although the social preference literature appeared vulnerable to small-study effects and imprecision. Locomotor activity measured during social interaction tests tended to be higher following NMDAR antagonists, whereas during social preference no consistent overall change was observed. In animals exposed to NMDAR antagonists, antipsychotics increased social behaviour, but these changes commonly co-occurred with reduced locomotion during social interaction tests, suggesting that improvements in social measures may partly reflect altered behavioural competition and time allocation rather than selective restoration of social functioning. Taken together, the evidence supports an overall link between NMDAR antagonism and reduced social behaviour, but the strength and interpretability of this signal depend on the paradigm and are constrained by heterogeneity and limitations in reporting.
The unpredictable chronic stress (UCS) protocol, originating in the 1980s, has contributed to depression research by inducing behavioral and physiological changes in rodents that resemble the symptoms observed in patients. Its translational potential led to widespread adoption, but adaptations and variations to the protocol have raised concerns about reproducibility. Over a decade ago, our laboratory adapted the UCS protocol for zebrafish (Danio rerio), aiming to bridge species-specific gaps in stress research. Since then, several studies have reported alterations in outcomes related to the clinical manifestations of stress-related disorders, providing evidence on the applicability of the model for testing drugs and other therapeutic strategies. However, there is substantial heterogeneity in protocols and research findings, hindering comparability across studies. To address these challenges, we describe a 14-day UCS protocol for adult zebrafish in detail, involving a series of varied stressors administered twice daily. This comprehensive protocol includes stressors, such as tank changes, net chasing, overcrowding, low water levels, and temperature fluctuations. Each step is designed to ensure reproducibility and to mimic the unpredictable and varied nature of stress experienced by humans. By establishing standardized procedures, we aim to enhance the consistency, reliability, and translational potential of UCS research using zebrafish, ultimately contributing to more robust and comparable findings across studies. © 2026 The Author(s). Current Protocols published by Wiley Periodicals LLC. Basic Protocol: UCS protocol for adult zebrafish.
This protocol describes the extraction of whole-body cortisol from adult zebrafish (Danio rerio) using an ether-based method, followed by quantification by enzyme-linked immunosorbent assay (ELISA). Samples are homogenised in PBS–gelatin buffer, extracted with ether, and reconstituted after solvent evaporation for hormone measurement. This workflow provides a reliable approach for assessing whole-body cortisol levels as a biomarker of physiological stress.
Stress-related disorders encompass diverse behavioral alterations, including impaired social functioning. The zebrafish ( Danio rerio ) is a valuable model for studying these phenomena, particularly because of its robust and ethologically conserved social behaviors. Unpredictable chronic stress (UCS) produces behavioral, physiological, and molecular changes in zebrafish that parallel core features of human anxiety and depressive disorders; however, its impact on social outcomes remains unclear. Here, we examined whether a 14-day UCS protocol alters social behavior in adult zebrafish using two complementary assays: the social preference test and the shoal cohesion test. Across two independent experiments, UCS did not elicit detectable changes in individual social approach or group-level cohesion. In contrast, UCS induced clear anxiety-like behavior in the novel tank test, validating the stress manipulation, with stressed fish displaying reduced vertical exploration and decreased time in the upper zone. Shoal cohesion measures showed a time-dependent decrease in both groups, consistent with habituation to the testing environment rather than a stress-specific effect. Together, these results suggest that social behavior in adult zebrafish is relatively resilient to UCS under the conditions tested, whereas anxiety-like responses are markedly affected. Future work should investigate whether factors such as stressor intensity, developmental stage, sex composition, or social hierarchy modulate the sensitivity of social behavior to chronic stress. ### Competing Interest Statement The authors have declared no competing interest. Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), 305968/2023-8
This protocol describes the preparation of gelatinised glass slides to improve the adhesion of histological sections during routine staining and immunohistochemical procedures. Slides are coated with a thin gelatin film stabilized with chromium potassium sulfate, providing a positively charged surface that enhances tissue adherence and prevents section detachment during extended incubations or multiple washing steps. The method is simple, economical, and suitable for delicate tissues, including zebrafish brain sections.
Plastic is considered an inert material with high durability and minimal to virtually no decomposition. However, when released into the environment, they can degrade into very small particles, forming micro- and nanoplastic particles (MNP). This systematic review and meta-analysis synthesized the evidence from controlled preclinical studies to investigate the neurological effects of MNPs in fish. Following a pre-registered protocol, we searched PubMed, Web of Science, and Scopus for studies exposing fish to virgin MNPs under controlled conditions, reporting behavioral or neurochemical outcomes relevant to central nervous system function. Data were synthesized using a hierarchical random-effects model with robust variance estimation. Fifty-nine studies, comprising 723 comparisons across 13 behavioral and neurochemical outcomes, were included in the meta-analysis. The analysis accounted for correlated effect sizes within shared control groups; and nested identifiers for study, control group, and effect size. The results indicate a high degree of heterogeneity in the effects of MNP exposure on behavioral or neurochemical parameters and a general lack of consistent evidence, except for reduced traveled distance in sensory-motor assays. Meta-regression examined whether developmental stage, exposure duration, and MNP size or concentration moderate these effects. No significant moderators were identified, except for catalase activity, where longer exposure reduced enzyme activity in larvae. The findings should be interpreted with caution, as reporting quality was generally low, with key methodological details often omitted. Additionally, publication bias was found for several outcomes, and influential case analyses revealed that a few studies disproportionately affected the overall estimates. Further studies are needed to clarify the impact of MNPs on fish neurobiology and behavior.
Ethnopharmacological relevance: linalool (LIN) and trans-nerolidol (NER) are terpene alcohols found in high concentrations in plant-derived essential oils used as a traditional treatment in many cultures. Several studies evaluating the effects of these essential oils and their isolated compounds have shown antiseizure, sedative, neuroprotective, and antioxidant properties in acute seizure models both in vitro and in vivo. Therefore, this study aimed to evaluate the effects of acute exposure to LIN or NER on a pentylenetetrazole (PTZ)-induced seizure model in adult zebrafish (Danio rerio). Methods: 240 adult wild-type zebrafish were randomly allocated to the experimental groups: control (dechlorinated water), 1% DMSO (vehicle), diazepam (50 μM DZP), and LIN or NER (4, 40 and 400 μM). Animals were exposed to the treatment solution (400 mL) for 10 minutes, taken to a washout beaker (dechlorinated water, 400 mL) for 5 minutes, and recorded in the test apparatus containing 10 mM PTZ for 20 minutes. Experienced researchers conducted a blinded analysis of behavioral seizure phenotypes using BORIS software. Additionally, locomotor activity was evaluated through ANY-Maze tracking software, ensuring precise and unbiased assessment of movement behaviors. Results: the highest concentration of LIN (400 μM) and NER (40 and 400 μM) increased the latency to reach clonic and tonic-like seizure stages while decreasing the seizure intensity. Interestingly, NER has shown a larger effect size than the positive control group DZP, and at a concentration of 40 μM, increased locomotor behavior. Conclusion: our findings show the antiseizure properties of LIN and NER in zebrafish acutely exposed to PTZ, delaying the time to reach the highest seizure stages and decreasing seizure intensity. These results are consistent with previous experiments conducted in mice and amplify the external validity of these compounds, highlighting their potential as antiseizure remedy candidates. ### Competing Interest Statement The authors have declared no competing interest.
Background NMDA receptor antagonists, such as ketamine, are widely used to model schizophrenia-related phenotypes in preclinical studies. While zebrafish have emerged as a promising model organism for neuropsychiatric research, few studies have characterized their behavioral responses to repeated ketamine exposure. Methods Three independent experiments were conducted to evaluate the acute, repeated and sustained behavioral effects of ketamine in adult zebrafish. In Experiment I, fish were exposed to 10, 20, or 40 mg/L ketamine once daily for five days, and submitted to the social preference (SPT) and open tank (OTT) tests on days 1 and 5, and re-exposed and re-tested on day 7 after a 48-hour washout. Experiments II and III assessed whether behavioral changes persisted following 5- or 14-day exposure protocols, with testing conducted 48 hours after the final treatment. Results Ketamine induced robust, concentration-dependent alterations in Experiment I: it reduced social interaction and increased locomotor activity in the SPT on all experimental days, while increased rotational behavior in the OTT on days 1 and 5. These effects did not intensify over repeated exposure and were not sustained after a 48-hour washout in either protocol (Experiments II and III). Conclusions The results support the utility of zebrafish for modeling acute behavioral responses to NMDA receptor antagonism, capturing features of schizophrenia-like phenotypes. However, no evidence of behavioral sensitization or lasting disruption was observed, diverging from rodent studies. Future studies should incorporate antipsychotic validation, neurochemical analyses, and alternative exposure strategies to further develop zebrafish as a translational model for psychiatric research. ### Competing Interest Statement The authors have declared no competing interest. All data supporting this study are publicly accessible via the Open Science Framework (osf.io/67y45) [[30][1]]. Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul, 24/2551-0001330-0 Conselho Nacional de Desenvolvimento Científico e Tecnológico, 305968/2023-8 [1]: #ref-30
Carbofuran (CF) is a carbamate class pesticide, widely used in agriculture for pest control in crops. This pesticide has high toxicity in non-target organisms, and its presence in the environment poses a threat to the ecosystem. Research has revealed that this pesticide acts as an inhibitor of acetylcholinesterase (AChE), inducing an accumulation of acetylcholine in the brain. Nonetheless, our understanding of CF impact on the central nervous system remains elusive. Therefore, this study explored how CF influences behavioral and neurochemical outcomes in adult zebrafish. The animals underwent a 96-hour exposure protocol to different concentrations of CF (5, 50, and 500 μg/L) and were subjected to the novel tank (NTT) and social preference tests (SPT). Subsequently, they were euthanized, and their brains were extracted to evaluate neurochemical markers associated with oxidative stress and AChE levels. In the NTT and SPT, CF did not alter the evaluated behavioral parameters. Furthermore, CF did not affect the levels of AChE, non-protein sulfhydryl groups, and thiobarbituric acid reactive species in the zebrafish brain. Nevertheless, further investigation is required to explore the effects of environmental exposure to this compound on non-target organisms.
Schizophrenia (SCZ) response to pharmacological treatment is highly variable. Quetiapine (QTP) administered as QTP lipid core nanocapsules (QLNC) has been shown to modulate drug delivery to the brain of SCZ phenotyped rats (SPR). In the present study, we describe the brain concentration–effect relationship after administrations of QTP as a solution or QLNC to SPR and naïve animals. A semimechanistic pharmacokinetic (PK) model describing free QTP concentrations in the brain was linked to a pharmacodynamic (PD) model to correlate the drug kinetics to changes in dopamine (DA) medial prefrontal cortex extracellular concentrations determined by intracerebral microdialysis. Different structural models were investigated to fit DA concentrations after QTP dosing, and the final model describes the synthesis, release, and elimination of DA using a pool compartment. The results show that nanoparticles increase QTP brain concentrations and DA peak after drug dosing to SPR. To the best of our knowledge, this is the first study that combines microdialysis and PK/PD modeling in a neurodevelopmental model of SCZ to investigate how a nanocarrier can modulate drug PK and PD, contributing to the development of new treatment strategies for SCZ.
Pesticides are widely used in global agriculture to achieve high productivity levels. Among them, fungicides are specifically designed to inhibit fungal growth in crops and seeds. However, their application often results in environmental contamination, as these chemicals can persistently be detected in surface waters. This poses a potential threat to non-target organisms, including humans, that inhabit the affected ecosystems. In toxicologic research, the zebrafish (Danio rerio) is the most commonly used fish species to assess the potential effects of fungicide exposure, and numerous and sometimes conflicting findings have been reported. To address this, we conducted a systematic review and meta-analysis focusing on the neurobehavioral effects of fungicides in zebrafish. Our search encompassed three databases (PubMed, Scopus, and Web of Science), and the screening process followed predefined inclusion/exclusion criteria. We extracted qualitative and quantitative data, as well as assessed reporting quality, from 60 included studies. Meta-analyses were performed for the outcomes of distance traveled in larvae and adults and spontaneous movements in embryos. The results revealed a significant overall effect of fungicide exposure on distance, with a lower distance traveled in the exposed versus control group. No significant effect was observed for spontaneous movements. The overall heterogeneity was high for distance and moderate for spontaneous movements. The poor reporting practices in the field hindered a critical evaluation of the studies. Nevertheless, a sensitivity analysis did not identify any studies skewing the meta-analyses. This review underscores the necessity for better-designed and reported experiments in this field.
It has been described that environmental enrichment (EE) exerts beneficial effects on cognitive and emotional performances, dendritic branching, synaptic density, neurogenesis and modulation of neurotrophic systems and neurotransmitters in rodents. However, the influence of EE on pharmacological and behavioral responses in animal models of psychiatric disorders has not been fully established. In this context, the aim of this study was to evaluate the influence of exposure to EE on mice behavior in the open field test (OFT) and forced swimming tests (FST), as well as the response to antidepressant drugs (fluoxetine 30 mg/kg and bupropion 30 mg/kg, p.o.). CF1 mice were exposed to an enriched housing condition at different developmental stages: from mating to postnatal day (PND) 55 (lifelong enrichment), from mating to PND21 (perinatal enrichment) and from PND21 to PND55 (post-weaning enrichment). At PND58 the male offspring were evaluated in the OFT and FST. BDNF gene expression in the hippocampus was determined through qPCR. Mice exposed to perinatal enrichment remained longer in the peripheral zone of the OFT and performed fewer grooming than mice housed under standard condition, and these effects were independent of drug treatment. Post-weaning and lifelong enrichment increased grooming behavior. Bupropion reduced grooming in all groups except in perinatal enriched. In turn, fluoxetine decreased grooming only in post-weaning enriched group. None of the enriched housing conditions altered the immobility time in the FST, which indicates that EE had no antidepressant-like effect. However, all enriched housing conditions abolished the anti-immobility effect of bupropion. None of the EE protocols affected BDNF hippocampal expression. The main conclusion is that mice behavior in the OFT is sensitive to alterations in the housing environment and depends on the developmental stage of exposure. Bupropion and fluoxetine yielded divergent responses depending on the housing condition, which suggests that EE modulates monoaminergic neurotransmission pathways.
Epilepsy is a prevalent neurological disease, affecting approximately 1–2
Background Altered redox state and developmental abnormalities in glutamatergic and GABAergic transmission during development are linked to the behavioral changes associated with schizophrenia. As an amino acid that exerts antioxidant and inhibitory actions in the brain, taurine is a potential candidate to modulate biological targets relevant to this disorder. Here, we investigated in mice and zebrafish assays whether taurine prevents the behavioral changes induced by acute administration of MK-801 (dizocilpine), a glutamate NMDA receptor antagonist. Methods C57BL/6 mice were intraperitoneally administered with saline or taurine (50, 100 and 200 mg/kg) followed by MK-801 (0.15 mg/kg). Locomotor activity, social interaction and prepulse inhibition of the acoustic startle reflex were then assessed in different sets of animals. Zebrafish were exposed to tank water or taurine (42, 150 and 400 mg/L) followed by MK-801 (5 μM); social interaction and locomotor activity were evaluated in the same test. Results MK-801 induced hyperlocomotion and disrupted sensorimotor gating in mice; in zebrafish, it reduced sociability while increased locomotion. Taurine was mostly devoid of effects and did not counteract NMDA antagonism in mice or zebrafish. Discussion Contradicting previous clinical and preclinical data, taurine did not show antipsychotic-like effects in the present study. However, it still warrants consideration as a preventive intervention in animal models of relevance to the prodromal phase of schizophrenia; further studies are thus necessary to evaluate whether and how taurine might benefit patients.
The use of zebrafish as a model organism is gaining evidence in the field of epilepsy as it may help to understand the mechanisms underlying epileptic seizures. As zebrafish assays became popular, the heterogeneity between protocols increased, making it hard to choose a standard protocol to conduct research while also impairing the comparison of results between studies. We conducted a systematic review to comprehensively profile the chemically-induced seizure models in zebrafish. Literature searches were performed in PubMed, Scopus, and Web of Science, followed by a two-step screening process based on inclusion/exclusion criteria. Qualitative data were extracted, and a sample of 100 studies was randomly selected for risk of bias assessment. Out of the 1058 studies identified after removing duplicates, 201 met the inclusion criteria. We found that the most common chemoconvulsants used in the reviewed studies were pentylenetetrazole (n = 180), kainic acid (n = 11), and pilocarpine (n = 10), which increase seizure severity in a dose-dependent manner. The main outcomes assessed were seizure scores and locomotion. Significant variability between the protocols was observed for administration route, duration of exposure, and dose/concentration. Of the studies subjected to risk of bias assessment, most were rated as low risk of bias for selective reporting (94%), baseline characteristics of the animals (67%), and blinded outcome assessment (54%). Randomization procedures and incomplete data were rated unclear in 81% and 68% of the studies, respectively. None of the studies reported the sample size calculation. Overall, these findings underscore the need for improved methodological and reporting practices to enhance the reproducibility and reliability of zebrafish models for studying epilepsy. Our study offers a comprehensive overview of the current state of chemically-induced seizure models in zebrafish, highlighting the common chemoconvulsants used and the variability in protocol parameters. This may be particularly valuable to researchers interested in understanding the underlying mechanisms of epileptic seizures and screening potential drug candidates in zebrafish models.
Epilepsy is among the most common neurological diseases, affecting more than 50 million people worldwide. Unfortunately, one-third of people with epilepsy fail to respond to any current treatment and present a decreased quality of life. Nevertheless, different studies suggest that epilepsies acquired from an initial insult as status epilepticus (SE) followed by epileptogenesis can be prevented. Therefore, it is necessary to establish animal models of epileptogenesis induced by SE. Thus, here we proposed an animal model of epileptogenesis triggered by SE that occurred during the neurodevelopment of zebrafish ( Danio rerio ). Zebrafish larvae at the 7th day post-fertilization (dpf) were randomly assigned to two experimental groups. One group was exposed to embryo medium. The other group was exposed to pentylenetetrazol (15 mM PTZ) to induce SE. At the 8th dpf, each larva was subjected to the open tank test (OTT) to analyze locomotion and behavioral parameters. After the OTT, each initial group was divided into two groups: animals maintained in embryo medium and animals exposed to PTZ (3 mM), and the susceptibility to PTZ-induced seizure-like behavior was analyzed. Data showed that animals submitted to SE on the 7th dpf showed altered locomotion and behavior 24 hours later. Interestingly, zebrafish larvae submitted to SE on the 7th dpf showed decreased latency to reach seizure-like behavioral stages when exposed to a low concentration of PTZ on the 8th dpf. Concluding, our results show that SE during neurodevelopment increases the susceptibility of zebrafish larvae to present PTZ-induced seizure-like behavior. Our study contributes to the establishment of a model of epileptogenesis in developing zebrafish. Finally, the next step is to improve this model by characterizing molecular, biochemical and physiological markers.### Competing Interest StatementThe authors have declared no competing interest.
The zebrafish ( Danio rerio ) is a model animal that is being increasingly used in neuroscience research. A decade ago, the first study on unpredictable chronic stress (UCS) in zebrafish was published, inspired by protocols established for rodents in the early 1980s. Since then, several studies have been published by different groups, in some cases with conflicting results. Here we conducted a systematic review to identify studies evaluating the effects of UCS in zebrafish and meta-analytically synthetized the data of neurobehavioral outcomes and relevant biomarkers. Literature searches were performed in three databases (PubMed, Scopus and Web of Science) with a two-step screening process based on inclusion/exclusion criteria. The included studies underwent extraction of qualitative and quantitative data, as well as risk-of-bias assessment. Outcomes of included studies ( n = 38) were grouped into anxiety/fear-related behavior, locomotor function, social behavior or cortisol level domains. UCS increased anxiety/fear-related behavior and cortisol levels while decreasing locomotor function, but a significant summary effect was not observed for social behavior. Despite including a substantial number of studies, the high heterogeneity and the methodological and reporting problems evidenced in the risk-of-bias analysis made it difficult to assess the internal validity of most studies and the overall validity of the model. Our review thus evidences the need to conduct well-designed experiments to better evaluate the effects of UCS on diverse behavioral patterns displayed by zebrafish.