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One Health

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https://hdl.handle.net/10388/14357
Health for all species is inextricably linked to challenges such as emerging diseases, water and food safety, and environmental degradation. We are working to develop scientific, public health and policy approaches that integrate human, animal and ecosystem health.

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Browsing One Health by Subject "Behaviour"

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    Neurodevelopmental and behavioural effects of waterborne selenite in larval zebrafish (Denio rerio)
    (Elsevier, 2025-02-26) Uddin, Md Helal; Ritu, Jinnath Rehana; Chivers, Douglas P.; Niyogi, Som
    Selenium (Se) is an essential element that becomes highly toxic to fish at elevated exposure levels. Although the neuro-behavioural effects of organic Se are well documented in adult fish, the effects of inorganic Se (selenite) on neurodevelopment and behaviour, particularly in early life stages, remain poorly understood. In this study, zebrafish embryos were exposed to different environmentally relevant concentrations of waterborne Se (0 (control), 10, 50, 100 μg/L; as selenite) from 4 hours post-fertilization to 30 days post-fertilization. We evaluated neurodevelopmental and behavioural outcomes, along with oxidative stress as a potential mechanism of selenite neurotoxicity. Fish larvae exposed to higher Se concentrations (50 and 100 μg/L) exhibited significant behavioural impairments, including reduced thigmotaxis and reflexive movement, spent significantly less time (60 %) near their conspecifics, and lower exploratory response (1.5 fold) to the novel object. These behavioural deficits were associated with elevated oxidative stress, as indicated by increased (5.4 fold) DCF-DA fluorescence intensity and dysregulation (0.6–6.4 fold change) of key antioxidant genes. Additionally, selenite exposure led to increased apoptotic cell death (p < 0.001), and reduced length (16 %) and weight (33–47 %) of zebrafish larvae in 50 and 100 μg/L Se exposure groups compared to the control group. Neurodevelopmental disruptions were evident through altered expression of dopaminergic (mao, th1, otpa; all p < 0.05) and serotonergic (tph2, pet1, 5ht2c; all p < 0.05) pathway genes, critical regulators of behaviour in fishes. Overall, our findings suggest that selenite-induced oxidative stress and neurodevelopmental gene dysregulation contribute to the observed behavioural impairments in developing zebrafish, highlighting the potential risks of Se exposure during early life stages.