The enriched tank: Zebrafish welfare, sex-specific behavior, and neuroendocrine insights

Zebrafish are becoming indispensable models in neuroscience and behavioral biology, enabling high-throughput studies on stress, cognition, and social behavior. Yet, variability in welfare conditions, environmental enrichment, rearing density, and tank design challenge reproducibility and cross-laboratory comparability. Emerging evidence shows that even minor modifications in environmental complexity, social structure, or light and water parameters can profoundly affect neuroendocrine signaling, cognitive function, and emotional reactivity. These factors interact strongly with sex, producing distinct stress-coping strategies and behavioral profiles that remain underexplored in standardized assays. Current protocols often prioritize throughput and simplicity at the expense of welfare, compromising reproducibility and biological realism.This Research Topic responds to this gap by integrating welfare science, sex-specific behavioral endocrinology, and methodological refinement to establish reproducible, welfare-driven standards for zebrafish behavioral testing. By positioning welfare optimization and sex differences as essential scientific variables, this project seeks to enhance both the validity and translational value of zebrafish behavioral research.This editorial project will integrate research on environmental enrichment, sex-specific behavioral endocrinology, and experimental design to improve reproducibility and welfare in zebrafish behavioral assays, positioning welfare optimization as a cornerstone of rigorous behavioral science. The goal is to establish new standards for reproducible zebrafish behavioral research that recognize the animal’s cognitive, social, and emotional complexity as an experimental asset rather than a source of noise.Subthemes:• Environmental enrichment and neurobehavioral plasticity in zebrafish: how environmental complexity modulates stress physiology, cognition, and emotionality.• Rearing density, social structure, and welfare metrics: defining optimal housing and social environments for reliable behavioral outcomes.• Sex-specific behavioral and neuroendocrine responses to enrichment and stress: exploring hormonal and behavioral dimorphisms.• Neuroendocrine and transcriptomic correlates of enrichment: linking welfare and behavioral improvement to hormonal and molecular mechanisms.• Standardizing behavioral assays: developing cross-laboratory reporting standards and reducing assay bias.• Individual variation, coping styles, and stress resilience: behavioral ecology perspectives on welfare and performance.• Integrated behavioral pipelines: novel paradigms capturing anxiety-like, cognitive, and social behaviors simultaneously within a single assay to enhance experimental efficiency and reproducibility. Topic editors: Svante Winberg, Pavla Hubená Source: https://www.frontiersin.org/research-topics/76298/the-enriched-tank-zebrafish-welfare-sex-specific-behavior-and-neuroendocrine-insights